A .4. yumofig «4* .~.uv_....u. mfiwfi: _ . a . 62w? . .kflfifn‘mflwnmu. . . s , firlmgw 2...» “125.9%. . . .a‘ (a. ¢fitF¢VJ§nu 4 .3 C .- .. .fluufi r” . s, a é umflmqfi re. - . . . Junk s. “was... 5 3b? 1%.. .. . . .2; nmfip...%mmma .42.. ‘u: v .. .n , 2.5. ‘ fir . I .2. 4.1;? 1 “3.53 u. :Rfifiv: \ . . ,. , Jan.» A . fin"? . . 1 , V r, . a “as...“m, . . “up.z~ (fa’ , .xfiufieniu. g? A BA. _‘ g .1.» ix: v 0.3.. in \ I; Ll». V .I ; ”Tar! i; 1 i; :3. 2!. u .. H. 2.... y :. z 2.... um... r. THESE 11“ fl ’3 :3 1-- .LIBRARY Michigan State University This is to certify that the thesis entitled Elemental Analysis of Glass Via Variable Pressure Scanning Electron Microscopy Energy Dispersive Spectroscopy (SEM—EDS) presented by Elizabeth Reeves has been accepted towards fulfillment of the requirements for Master's degreein Criminal Justice F . :1 15450: professd: [ 0 l l 3.2: 0 Date 0.7639 MS U is an Affirmative Action/Equal Opportunity Institution PLACE IN RETURN Box to remove this checkout from your record. To AVOID FINES return on or before date due. MAY BE RECALLED with earlier due date if requested. DATE DUE DATE DUE DATE DUE 6/01 cJCIRC/DateDuepSS-pJS ELEMENTAL ANALYSIS OF GLASS VIA VARIABLE PRESSURE SCANNING ELECTRON MICROSCOPY—ENERGY DISPERSIV E SPECTROSCOPY (SEM-EDS) By Elizabeth Reeves A THESIS Submitted to Michigan State University In partial fulfillment of the requirements For the degree of MASTER OF SCIENCE Department of Criminal Justice 2001 cor enl var Iran Phi USE aux. RUE: Star ABSTRACT ELEMENTAL ANALYSIS OF GLASS VIA VARIABLE PRESSURE SCANNING ELECTRON MICROSCOPY-ENERGY DISPERSIVE SPECTROSCOPY (SEM-EDS) By Elizabeth Reeves The forensic examination of glass samples has traditionally relied upon comparison of the physical and optical properties between two samples. However, the enhancement of quality control measures in the manufacture of glass has led to decreased variability of these properties between samples of different origins. The comparison of trace elements in glass has been shown to be advantageous over the comparison of physical and optical properties alone. SEM-EDS is an analytical technique that may be used to analyze elemental composition on the surface of a sample of glass. A LEO 435 VP SEM coupled with an EDAX Phoenix EDS system was automated for elemental analysis of glass. The automated method analyzed tempered automotive glass at variable pressure (10 Pa) for 100 live seconds in five iterations. Elemental ratios (Sn/Na, Na/Al, Mg/Al, Na/Mg, Ca/N a, Ca/K) were averaged and standard deviations calculated. A statistical model for inclusion was developed. Fifty samples of tempered automotive glass were examined by refractive index measurement and by the automated SEM-EDS method and statistical model for inclusion. When used alone, both the comparison of glass based on refractive index measurement and SEM- EDS comparison yielded a false inclusion in 7.6% of the cases. However, when elemental analysis was used in tandem with the measurement of refractive index, only 0.8% of the cases were falsely included. WC ins ACKNOWLEDGMENTS The author wishes to thank those who have ensured the success of this project through their support. First, the Michigan State Police Forensic Laboratory of Lansing, Michigan must be acknowledged for the use of the instrumentation and chemicals used in this study. Chris Bommarito of the Michigan State Police Laboratory is deserving of specific gratitude for his concept, guidance, patience, and constructive criticism. Also, the author would like to thank Dr. Jay Siege] of Michigan State University for his advice and instruction. iii TABLE OF CONTENTS List of Tables ........................................................................................................ v List of Figures .................................................................................................... vii Chapter 1 Introduction .......................................................................................................... 1 Forensic Importance and Analysis of Glass ................................................... l The Problem to be Studied ............................................................................. 2 Purpose of the Study ....................................................................................... 3 Hypothesis ....................................................................................................... 4 Limitations ...................................................................................................... 4 Methodology ................................................................................................... 4 Chapter 2 Scanning Electron Microscopy and the Analysis of Glass ................................. 7 Scanning Electron Microscopy ....................................................................... 7 Manufacture of Glass ...................................................................................... 8 Elemental Analysis of Glass ........................................................................... 9 Summary ....................................................................................................... 10 Chapter 3 Review of Literature .......................................................................................... 11 Comparison of Glass Based Upon Refractive Index Measurement ............ 11 Elemental Analysis ....................................................................................... 12 Summary ....................................................................................................... 13 Chapter 4 Development of Suitable SEM-EDS Operating Parameters ............................ 15 Automation of the SEM with EDAX ........................................................... 15 Procedure .................................................................................................. 18 Parameters for Analysis ........................................................................... 20 Statistical Model for Inclusion ................................................................ 23 Summary .................................................................................................. 27 Examination of the Effect of Sample Tilt Angle ......................................... 27 Procedure .................................................................................................. 28 Summary .................................................................................................. 29 Application of Variable Pressure SEM-EDS to Glass Analysis ................. 30 Procedure .................................................................................................. 30 Elemental Analysis ....................................................................................... 32 Overall Results .............................................................................................. 32 Summary ....................................................................................................... 33 TABLE OF CONTENTS, continued Chapter 5 Conclusions and Discussion .............................................................................. 34 Conclusions ................................................................................................... 34 Discussion ..................................................................................................... 35 Future Research ............................................................................................ 37 Beyond SEM-EDS ........................................................................................ 39 Appendices ......................................................................................................... 40 Appendix I Glossary .............................................................................................................. 41 Appendix II Elemental Data: high vacuum, low vacuum, and sputter coated samples ....... 43 Appendix III Elemental Data: tilt angle effects ....................................................................... 49 Appendix IV Summary of Elemental Ratio Comparisons in the Establishing of a Statistical Model for Inclusion ........................................................................ 53 Appendix V Refractive Index Comparisons .......................................................................... 55 Appendix VI 186 Elemental Comparisons of Samples not Distinguished by Refractive Index ................................................................................................. 58 Appendix VII Summary Data for Refractive Index and Elemental Analysis Comparisons. 105 Notes ................................................................................................................. 107 Bibliography ..................................................................................................... 109 LIST OF TABLES Table 1.1 Elemental ratios constructed for all elemental comparisons .............................. 5 Table 4.1 Sample spreadsheet used to calculated elemental ratios, averages and standard deviations from data obtained in the automated analysis ................................................................................... 17 Table 4.2 Sample calculation for Sample 1, Na/Al ratio examined under low vacuum ......................................................... 19 Table 4.3 Comparison of standard deviation as a percent of the average ratios for high vacuum, low vacuum, and sputter coated samples ................... 20 Table 4.4 Comparison of spot mode vs. reduced raster analysis of glass from three sources .............................................................................................. 21 Table 4.5 Comparison between three iterations and five iterations of each sample ........ 22 Table 4.6 Number and percent of same source automotive glass included and excluded based on statistical model for inclusion ...................................... 25 Table 4.7 Number and percent of same source samples included, excluded, or deemed inconclusive using the statistical model for inclusion .................... 26 Table 4.8 Summary of Data ............................................................................................... 32 Table 5.1 Comparison of the discriminating power of refractive index measurement and SEM-EDS when used alone and in combination ................ 36 Appendix Table 2.1: Elemental Data: high vacuum, low vacuum, and sputter coated samples ....... 43 LIST OF TABLES, continued Appendix Table 3.1 Elemental Data: Tilt Angle Effects ................................................................... 49 Appendix Table 4.1 Summary of Elemental Ratio Comparisons in the Establishing of a Statistical Model for Inclusion ................................................................... 53 Appendix Table 5.1: Refractive Index Comparisons .......................................................................... 55 Appendix Table 6.1: 186 Elemental Comparisons of Samples not Distinguished by Refractive Index .............................................................. 58 Appendix Table 7.1: Summary of Refractive Index Data ................................................................. 105 Appendix Table 7.2: Summary of Elemental Comparisons for Samples with Different Refractive Indices ............................................................................ 105 Appendix Table 7.3: Summary of Elemental Comparisons for Samples with Indistinguishable Refractive Indices ............................................................... 105 Appendix Table 7.4: Summary of Elemental and Refractive Index Comparisons .......................... 106 Appendix Table 7.5: Summary of All Comparisons ......................................................................... 106 LIST OF FIGURES Figure 3.1 The mathematical relationship between the speed of light in a vacuum and the speed of light in a transparent medium determines the refractive index of the sample ................................................... 11 Figure 4.1 The tilt angle of the surface of a sample may range from perfectly flat to highly sloped ................................................................... 28 miner 1: Introduction Forensic Importance and Analysis of Glass It has long been recognized that the analysis of glass is an important tool of the forensic laboratory. In many cases, glass can be a valuable piece of evidence that links a suspect to a crime. For example, the glass fragments found in the clothing of a hit-and- run victim may be compared to glass from the broken window of the suspect’s car. Such a comparison might traditionally have been accomplished by comparing the optical and physical properties of the two samples to determine a possible common origin. Thus, the forensic analysis of glass has traditionally relied upon the variability of optical and physical properties amongst glass samples of different origins. However, the enhancement of quality control measures in the manufacture of glass has led to a decrease in the variability of these properties between glass samples, even those from different sources. This decrease in variability of optical and physical properties has highlighted the advantages of also comparing the trace elements present in glass samples, rather than relying on optical and physical properties alone. The elemental analysis of glass may be accomplished by such instrumental methods as neutron activation analysis, inductively coupled plasma mass spectrometry, and atomic absorption. Also, scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS) may be used to detect the presence of trace elements in glass samples. This study focuses on the elemental analysis of glass by variable pressure SEM- EDS as a means to distinguish between samples from different sources that share similar optical properties. Some components of this study include the demonstration of appropriate instrument operating parameters and the implementation of a statistical model for inclusion. pt 88] sar 616 this firs suit First for 11 The Problem to be Studied The analysis of glass samples in the forensic laboratory traditionally relies on comparison of the optical and physical properties of the samples. Optical comparison of glass is made by comparing the refractive index of the questioned sample to that of the known sample. Physical comparison is made by comparing the color and thickness of the two samples, and also by comparing the densities of the two samples. However, it has been shown that the refractive index of a piece of glass is directly related to its density and the correlation between the two properties is 0.93.i With such a relationship, forensic scientists generally measure only refractive index as the measurement of density is much more difficult and does not add to any conclusions formed after comparison of refractive index. The forensic scientist would thus compare two samples based on color, thickness and optical properties. Samples with similar properties are concluded to have possibly arisen from the same source. It has been demonstrated that samples with similar optical properties may be better distinguished by comparing the elemental composition of the samples.ii Thus, the fundamental question posed and answered by this study is: may two samples of glass with similar optical properties be distinguished by analyzing for specific elements using variable pressure SEM-EDS? However, in order to arrive at an answer to this primary question, a method by which elemental analysis may be accomplished must first be demonstrated. In this study, variable pressure SEM-EDS will be shown to be a suitable method by which elemental composition can be examined in a substance such as glass. Therefore, the problem to be studied is best answered in a step-wise fashion. First, the appropriate operating conditions of the SEM-EDS system must be established for the analysis of glass. Subsequently, the ability of SEM-EDS to distinguish between samples of glass originating from different sources but sharing similar Optical properties will be demonstrated. Purpose of the Study As described, it is becoming increasingly important to procure an analytical method that is able to supplement the traditional optical analyses. Such a method should be able to detect variation and discriminate between pieces of glass that did not come from the same source. However, with hundreds of thousands of glass formulationsi“, it is desirable that the proposed method be suitable for analysis of every type of glass encountered in the forensic laboratory. SEM-EDS is a method that is potentially able to distinguish between pieces of glass from different sources, and is applicable to a large number of elemental compositions. In this study, the combination of SEM—EDS and analysis of optical preperties will be researched in order to highlight the enhanced discriminating power of associating optical analysis with SEM-EDS as opposed to optical analysis alone. Also, this study will focus upon the development of a statistical model for inclusion based on elemental ratios, and the demonstration of optimal SEM instrument parameters for glass analysis. Research of this nature will have several beneficial outcomes. First, as this research is being conducted in conjunction with the Michigan State Police, this project will serve to implement a protocol for the comparison of glass samples based upon the combination of measurement of optical properties and elemental analysis. This protocol will be used by the Michigan State Police Forensic Science Division in casework situations. Secondly, this study will highlight the superlative power of elemental analysis to discriminate between glass samples from different sources that share the same refractive index. Finally, this study will demonstrate effective instrumental parameters for variable pressure SEM-EDS analysis of glass, and present a statistical model for inclusion based on elemental ratios. In combination, these benefits will enhance the ability of the forensic scientist to discriminate between samples of glass with similar optical properties thereby reducing the possibility of a suspect being falsely implicated in a crime. Hypothesis Upon development of appropriate instrumental operating parameters and construction of a statistical model for inclusion, it is predicted that performing elemental analysis subsequent to Optical analysis will result in the increased ability of the forensic scientist to distinguish between samples of glass not able to be distinguished by optical analysis alone. This is predicted to be so, as the manufacturing of glass (discussed in Chapter 2) creates a product with uniform optical properties but introduces trace elements into the glass in a random fashion. This creates the variability of elemental composition that is predicted to assist the forensic scientist in distinguishing between similar glass samples. Furthermore, this hypothesis is supported by the work of Reeve, Mathieson and F ong, which demonstrated that 100% of 81 glass samples analyzed could be distinguished by combining optical analyses with traditional high vacuum SEM-EDS.” Limitations This study focuses exclusively on the use of variable pressure SEM-EDS as a method for elemental analysis of glass and thus will not examine other instrumentation such as neutron activation or mass spectrometry techniques. Furthermore, the entirety of the samples examined in this study will be tempered automotive glass. Methodology This study contains primary research in elemental analysis by variable pressure SEM-EDS, and optical analysis by refractive index measurement. The research was conducted at the Michigan State Police Laboratory in East Lansing, Michigan, using a LEO 435 variable pressure SEM with EDAX Phoenix x-ray detector and software. Refractive index measurements were taken using the Emmond's double variation method using equipment and techniques already in place at the East Lansing Laboratory. Elemental analysis was conducted by quantitating the amount of tin, sodium, aluminum, magnesium, potassium and calcium on the surface of each glass sample. The amount of each element in each piece of glass was used in constructing specific elemental ratios (Table 1.1) that were calculated for each sample. in:Sodium Sn/Na lMagnesiumzAluminum Mg/Al SodiumzAluminum Na/Al Sodiuszagnesium Na/Mg Calcium:Sodium Ca/N a Calcium:Potassium Ca/K Table 1.1: Elemental ratios constructed for all elemental comparisons. Suitable operating parameters for the variable pressure SEM were established by comparing the standard deviation of the elemental ratios for each sample. The criteria that were examined to establish appropriate operating parameters include: size of raster area on the sample, the number of repeat measurements for each sample, the pressure of the sample chamber, and if the sample requires conductive coating. Furthermore, the effect of tilt angle on the sample was investigated. Upon determination of appropriate operating parameters, a statistical model for inclusion was developed. A statistical model was employed to distinguish between the natural variation inherent in a piece of glass and the variation that exists between pieces of glass from different sources. This model established a statistical range applicable to each sample so that when comparing two samples of glass, the analyst is able to determine if the results are inclusive (the samples could have come from the same source) or exclusive (the samples did not come from the same source). Finally, 50 tempered automotive glass samples were collected from local junkyards and subjected to analysis by variable pressure SEM-EDS and refractive index measurement. Subsequent pair-wise comparisons yielded 2550 comparisons, upon which the number of false inclusions by refractive index and by SEM-EDS was calculated. Chapter 2: Scanning Electron Microscopy and the Analysis of Glag Scanning Electron Microscopy The scanning electron microscope is an instrument that is primarily used to produce magnified images of a sample. Fundamentally, the scanning electron microscope (SEM) uses a beam of electrons to excite the electrons on the surface of the sample. These excited electrons, called secondary electrons, are emitted from the surface of the sample and are captured by a detector that enables a magnified image to be projected to a television or computer monitor. Along with the secondary electrons, x- rays are also emitted from the surface of the sample. Each x-ray emitted has a specific energy characteristic of the element that produced it. An x-ray detector may be coupled with the SEM permitting detection and spectroscopic analysis of the emitted x-rays. This spectroscopic capability is referred to as Energy Dispersive Spectroscopy or SEM-EDS. SEM-EDS is traditionally performed in a high vacuum environment in order to maintain the electron beam, and generally with samples that are conductive or semi- conductive. Non-conductive samples, such as glass, are problematic to analyze under the traditional SEM vacuum conditions. This is because a nonconductor tends to build up electrical charge when bombarded with the beam of electrons. This built up electrical charge deflects the secondary electrons resulting in inaccurate quantification of elemental concentrations. In order to prevent charging artifacts, non-conductive samples are commonly coated with a conductive substance, such as carbon, to prevent the build up of negative charge. Usually, the sample is coated with carbon in a process called sputter coating. However, in a forensic case, it is not desirable to sputter coat evidentiary samples as this process adds foreign material to the evidence, thereby altering the composition of the evidence prior to analysis. In a high vacuum environment it may be possible to perform SEM-EDS on a non- conductive sample without a conductive coating provided the proper accelerating voltage the pn to M Spl ch: the dis are cle: ma Ma is selected. Charging effects may be reduced if the accelerating voltage is chosen so that the electron emission coefficient is greater than or equal to 1.0. However, selection of a proper accelerating voltage is complicated by the fact that the electron emission coefficient varies between samples and between different points on the same sample, which makes the technique inordinately difficult to employ in an automated analysis. Recently, non-conductive samples have been able to be analyzed without being sputter coated by use of a variable pressure SEM. The variable pressure SEM is better able to handle glass and other non-conductive samples as it maintains the sample chamber at a much higher pressure (approximating that of the outside environment) than the traditional SEM. The higher pressure in the variable pressure SEM is able to dissipate the built up electrical charge on the sample, thereby reducing charging effects and improving the accuracy of elemental analysis. Thus, it is possible to accurately analyze a non-conductive sample such as glass by using a variable pressure SEM. The analysis of glass by SEM-EDS is performed by examining a point or small area on the surface of the glass for trace elements such as tin and sodium. These elements are deposited randomly on the surface of the glass as a result of the manufacturing process. Manufacture of Glass A process first developed in 1959 is used in the manufacture of flat glasses such as those found in windowpanes." This process begins with the mixing of silica, metals (such as sodium and magnesium), metal oxides (such as calcium oxide), and recycled glass. These raw materials are passed from a mixing silo into a melting furnace where they are heated to become molten. The molten glass is then poured continuously from the fumace onto a shallow bath of molten tin. As the glass is highly viscous and the tin is very fluid, the two do not mix and the glass spreads out to form a flat surface. The molten glass floats on top the bath of tin, and is gradually cooled as it floats down the tank. Glass prepared in this way is termed "float glass". The float glass forms a continuous ribbon over three meters wide and three- to nineteen millimeters thick.Vi The thickness of the glass is controlled by the speed at which the solidifying glass ribbon is drawn off the bath.Vii The glass is then cooled, subjected to quality checks, and cut into sheets. As mentioned in the previous chapter, manufacturers assure the quality of their product by checking optical and physical properties, such as the density and refractive index of the glass. This process cheaply and quickly produces glass with virtually parallel surfaces and uniform thickness. However, it is by this same process, from the raw materials to the float bath, that elemental variation is introduced to the glass, providing forensic scientists with a useful characteristic for analysis. Although the main composition of the glass is carefully controlled, metallic elements may be randomly deposited on the glass as it passes over the bath of molten tin. The float tank containing the molten tin is operational 24 hours a day for approximately ten years."iii Over this period of time, metals are randomly introduced to the molten tin as the melting furnace corrodes, and metals from the glass ribbon are retained in the tin bath. As the molten glass ribbon floats over the tin bath, tin and the other random metals present in the float tank adhere to the glass, giving the ribbon of glass a coating of metallic elements on the side of the glass that was in contact with the molten tin (known as the "float side"). As the concentrations of the metals present in the tin bath is consistently changing, the concentration of trace metals on the float side of the glass will vary between different areas of the glass ribbon. Elemental Analysis of Glass As the float side of the glass now contains specific amounts of trace metals, SEM- EDS may be used to determine which metallic elements are present on the surface of the glass, and how much of each element there is. For example, some metallic elements commonly found on glass include aluminum, calcium, sodium, tin and magnesium. It has been demonstrated that trace element concentrations are relatively constant across a sheet of glass, and vary between different sheets of glass.ix Thus, the concentrations of these elements on one piece of glass can be compared to the concentrations found on a second piece to determine if the two pieces could have originated from the same sheet of glass. Summary The process by which float glass is manufactured results in variation in the concentration of trace metals on the float side of the glass. These metals can be analyzed by SEM-EDS, and the concentration of the metals present on different pieces of glass can be compared to determine if the glasses could have come from the same source. 10 Q re fr spe ligl ind pas con Pro C011 Chapter 3: Review of L_it_er_a_tu£ Comparison of Glass Based Upon Refractive Index Measurement Optical comparison of glass is most commonly based on the measurement of the refractive index of the glass. Refiactive index is defined by the relationship between the speed of light in a vacuum and the speed of light in a transparent medium, such as glass. In practical terms, the speed of light in a vacuum is considered to be equal to the speed of light in air. The refractive index is calculated to be a numerical value, such as 1.5, which indicates that for a specific sample, the speed of light is decreased by 1.5 times when it passes from the air into the sample. S eed of li tin a vacuum Refractive _ p gh Index Speed of light in a transparent medium Figure 3.1: The mathematical relationship between the speed of light in a vacuum and the speed of light in a transparent medium determines the refiactive index of the sample. As discussed in Chapter 2, refractive index is monitored for purposes of quality control in the manufacturing process. The increasing sophistication of the manufacturing procedures and the effect on refractive index is demonstrated by GA. Brown, who compared the distribution of refractive indices of older (greater than 30 years old) and newer (less than 30 years old) glass samples" Brown found that the unimodal distribution of sheet glass had a refractive index range of 1.5155 to 1.5159. However, the total spread of refractive indices of older glass was greater than that of newer glass. According to Brown, the decreased range of reflective indices in newer glass is due in part to the change in manufacturing procedures over time. This observation has been made by other scientists, including M.D.G. Dabbs who agrees with Brown's conclusion that the 11 "difference in refractive index distribution with the age of the glass is caused by improved quality control of raw materials and composition" of the glass.Xi In the forensic laboratory, the narrow distribution of refractive indices was observed by D. Hickman who stated that the most often occurring glass in casework was colorless glass with a refractive index of 1.5125 to 1.5250."ii The observations of Brown and Hickman indicate that the range of refractive indices for colorless glass is exceedingly narrow, with differences occurring only at the hundredths-, or thousandths-decimal place. As improvements in the manufacturing process serve to narrow this range even further, it is becoming increasingly important to use additional means of comparison to discriminate between two glass samples. Elemental Analysis The significance of elemental composition was demonstrated by Koons and Buscaglia in 1999. Their research measured elemental concentrations of several elements by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). In pair-wise comparison of the elemental compositions of over 200 samples, most samples could be distinguished by their elemental composition."iii The researchers concluded that the measurement of elemental concentration and refractive index provide a "high source- discrimination capability" between glass fragments.“ Also operating on the premise that trace elements arising from the manufacturing process can characterize glass samples, J. Andrasko and AC. Maehly sequentially used refractive index, SEM-EDS, and emission spectroscopy to distinguish fragments of glass."v The researchers found that SEM-EDS demonstrated good reproducibility of results when specific elemental ratios (Na/fMg, Na/Al, Mg/Al, Ca/N a, Ca/K and Ba/Ca) were used for comparison. When these elemental ratios were compared between 29 samples with indistinguishable refractive indices, only 4 remained indistinguishable. Emission spectroscopy was performed subsequent to SEM-EDS and 2 samples remained 12 indistinguishable. Based on this result, Andrasko and Maehly recommend that SEM- EDS be performed on samples of glass that are indistinguishable by refractive index alone.“ Emission spectroscopy may be used subsequent to SEM-EDS, however the researchers caution that the technique is destructive and requires at least one milligram of sample -rest1ictions that may preclude analysis of many forensic samples. Andrasko and Maehly also analyzed the effect of sample tilt angle on the calculation of elemental concentrations."Vii The sample tilt angle is the angle to which the surface of the sample is tilted in relation to the stage or surface of another sample. At a sample tilt angle of sixty degrees, the Na/Mg ratio remained relatively constant, although the signal intensity (and elemental concentration) varied highly. Therefore, the researchers concluded that in order to obtain reproducible results carefirl attention must be paid to surface geometry and the manner in which the sample is mounted for analysis. In similar research, V. Reeves, J. Mathiesen, and W. Fong investigated the ability of SEM-EDS to distinguish between samples of glass based on a series of elemental concentrations ratioed to the concentration of calcium in the sample.“ii Using high- vacuum SEM-EDS, the researchers report that two out of eighty-one samples were indistinguishable by SEM-EDS alone. However, when coupled with refractive index measurement, 100% of the samples were able to be distinguished. From these results, and the results of the previous research, it has been demonstrated that elemental analysis can lead to discrimination of glass samples. Most important is the observation of the increased discrimination capability that is achieved when refractive index measurement is coupled with SEM-EDS in the analytical scheme. Summary While refractive index measurement is a widely accepted, convenient, and sensitive technique for glass comparisons, its power to discriminate between glass samples from different sources is diminished. Improved quality control in the 13 manufacture of glass has decreased the distribution of refractive indices to a range that differs only in the thousandths place.“ Consequently, forensic scientists must turn to more discriminating analytical techniques, specifically elemental analysis. Comparative analysis of the elemental composition of glass samples is appropriate for forensic work as the elemental composition of the glass is more variable which may permit the discrimination of two otherwise indistinguishable samples. Various methods of elemental analysis have been investigated, including SEM-EDS. It has been demonstrated that when refi'active index measurements are combined with elemental analysis by SEM—EDS, a high proportion of physically indistinguishable 1 samples may be distinguished.xx xx 14 sup ED | qua. the 1 anal. expe glass First. Seton for inc autonu the sun SEM-E1 Automa T an31131.8 C ficflhak,; mksmdy All be Perform requires 1h; Chapter 4: Development of Suitable SEM-EDS Operating Parameters As it is becoming increasingly important to procure an analytical method to supplement the traditional optical analyses of glass, the use of a variable pressure SEM- EDS system was investigated. This system allows for the identification and quantification of trace elements, and so is suitable for the analysis of elements found on the float surface of a sample of glass. However, before SEM-EDS is introduced into the analytical scheme, a protocol for appropriate use must be prescribed. Therefore, through experimentation, a suitable set of operating parameters was developed for the analysis of glass by variable pressure SEM-EDS. The issues addressed in the method developed by this research are four-fold. First, the appropriate sample chamber pressure level for this analysis was investigated. Second, electron beam scanning parameters were established. Next, a statistical model for inclusion was prepared and evaluated using repeat analyses of single-source automotive glass. Finally, the effect of sample tilt-angle was investigated to determine if the surface orientation of the sample limited the precision of elemental analysis. However, to facilitate the investigation of these issues, the basic operation of the SEM-EDS system was automated. Automation of the SEM with EDAX The EDAX Phoenix EDS system allows for the automation of the SEM-EDS analysis of multiple samples. The automation of the system was set up in order to facilitate and expedite the analysis of the large volumes of samples that were analyzed in this study and in some casework situations. Although the system may be automated, there are multiple requirements that must be performed by the operator in order for proper operation of the system. The system requires that the operator choose and prepare his own samples, and insert them into the 15 stage in the SEM sample chamber. The operator must then choose the parameters of pressure, working distance and elements to be quantitated. Also, the operator must indicate the number of repetitions of the analysis and the size of the area on the sample to be analyzed. Upon completion of these tasks, the collection of data is performed automatically by the EDAX system. Sample preparation for the automated analysis is quite straightforward. First, a small cube of tempered automotive glass was washed in several milliliters of acetone in a sonic bath. The sample was sonicated for five minutes and then removed from the bath. The sample was then observed under short wave ultra violet light (254 nm) to determine which side was the float side of the glass. The float side fluoresced a bright yellow and the sample was mounted float-side up on an aluminum SEM stub with double-sided carbon tape. The sample was then placed in the stage of the sample chamber in the SEM. The stage may hold up to seven samples, and so the automation program was set up to analyze fi'om one to seven samples. The program was arranged to analyze for the elements tin (Sn), sodium (Na), magnesium (Mg), aluminum (Al), potassium (K), and calcium (Ca). These elements were chosen for analysis because they are commonly used in float glass manufacture as raw materials or components of the float bath, and so would be expected to be found in samples of float glass. Each sample was scanned for 100 live seconds at a count rate of approximately 2500 counts per second. In a run of multiple samples, the analysis begins at sample one. Sample one is scanned for 100 live seconds and then the stage automatically moves to sample two so that sample two is scanned next. For a second iteration, the samples are scanned alternately so that no sample is scanned twice in a row. This alternating analysis was designed to minimize potential problems such as charge build up on the sample, and to ensure that instrumental variation does not accrue between the analysis of sample one and sample two. Upon completion of analysis, the elements 16 are quantitated automatically and concentrations are tabulated. The elemental data is then manually transferred to a spreadsheet template that calculates the elemental ratios listed in Table 1.1. The spreadsheet also calculates the average elemental ratio for each ratio in a sample, and the standard deviation for multiple analyses is also calculated (Table 4.1). Sample lNa/Al A1 14.01652 4.206948 Std Dev= 1.300133 Std Dev= 0.458536 Lo= 10.11612 Lo= 2.83134 Hi= 17.91692 Hi= 5.582556 4.283033 1.484822 Std Dev= 0.206776 Std Dev= 0.101284 Lo= 3.662706 Lo= 1.180971 Hi= 4.90336 Hi= 1.788674 Table 4.1: Sample spreadsheet used to calculate elemental ratios, averages and standard deviations from data obtained in the automated analysis. Upon construction of the automated analysis program and calculations template, the operating parameters for the analysis of glass were established. First, suitable sample chamber pressure conditions were established. Selection of Suitable Sample Chamber Pressure Conditions As described in Chapter 2, SEM-EDS is generally performed in a vacuum with samples that are conductive. When a non-conductor such as glass is analyzed under high vacuum conditions in the SEM, it will build up a negative charge if it is not coated with a conductive coating. Rather than using a conductive coating, non-conductive samples may also be analyzed under a low vacuum (higher pressure) to reduce the charging effects present at higher vacuum levels. 17 El wi Prt auto sam scan the e autor samp and st Pa A and Sta was Sp] high \a To determine if analysis under a low vacuum is appropriate for SEM-EDS analysis of glass, fourteen tempered automotive glass samples were analyzed by SEM- EDS at high vacuum, then at low vacuum, and finally at high vacuum after being coated with carbon. Procedure The fourteen samples, divided into two groups of seven, were analyzed by the automated elemental analysis program previously implemented on the SEM-EDS. The samples were first analyzed at high vacuum (0.01 Pa). Each sample was alternately scanned in one area five separate times for 100 seconds each time. The quantitation of the elements tin, sodium, magnesium, aluminum, potassium, and calcium was performed automatically by the EDAX system. The elemental concentrations present in each sample were then transferred to the spreadsheet where the appropriate ratios, averages and standard deviations were calculated. Next, the same samples of glass were re-analyzed under a low vacuum level of 10 Pa. Again, the concentrations of the six elements were calculated and the ratios, averages and standard deviations were tabulated in the spreadsheet. Finally, each sample of glass was sputter coated with carbon. The carbon-coated samples were then analyzed under high vacuum (0.01 Pa) and elemental ratios were again calculated. This process resulted in three sets of elemental ratios, averages and standard deviations: one set for each pressure level. Within each data set were elemental ratios, averages and standard deviations that were calculated individually for each of the fourteen samples. For example, the average of the five measurements of the Na/Al ratio for sample one were calculated at each pressure level. The value of one standard deviation from this average was also calculated at each pressure level. Then, to determine the standard deviation as a percent of the average, the standard deviation was 18 divided by the corresponding elemental ratio average and the result multiplied by 100% (Figure 4.2). This calculation was performed at each pressure level. Ratio Avg. Std Dev Std Dev as % Na/Al 6.571 0.3113 (0.3113/6.571) x 100% = 4.737 Figure 4.2: Sample calculation for Sample 1, Na/Al Ratio Examined under Low Vacuum. The same calculations were performed for the other elemental ratios of sample one, and also for each of the other samples. The procedure was repeated for fourteen glass samples, each analyzed at 3 different pressure levels. Upon completion of the calculations for each of the fourteen samples, there were 252 total standard deviations calculated as a percentage of the elemental ratio average. Eighty-four of these standard deviations belonged to the data collected at low vacuum. These eighty-four values were averaged to reach the average standard deviation from the elemental ratios collected at low vacuum. The averages for the data collected at high vacuum and with sputter coated samples were also calculated. The results of these calculations were compared to determine the most precise method of analysis. As shown in Table 4.3, the lowest standard deviation as a percent of the average was shown by those samples analyzed at low vacuum. This indicates that the most precise method of analysis of glass by SEM-EDS requires that the samples be analyzed under low vacuum. The data collected fi'om elemental analysis at high vacuum was less precise than the other two methods. And while the use of sputter-coated samples was more precise than analysis of uncoated samples at high vacuum, it was less precise than analysis of uncoated samples at the low vacuum level. 19 Standard Deviation as Mode of Operation Percent of Ratio Low Vacuum 11.45 igh Vacuum 19.83 Sputter Coated 16.2 Table 4.3: Comparison of Standard Deviation as a Percent of the Average Ratios for High Vacuum, Low Vacuum, and Sputter Coated Samples. Therefore, it is concluded that a low vacuum level is most favorable to use in SEM-EDS analysis of glass samples, as it is more precise. Parameters for Analysis The two parameters that must be established for all analyses of glass by this automated SEM-EDS method are the number of iterations for each sample, and the size of the area of analysis. To determine the appropriate size of the area of analysis, seven samples of glass were obtained fi'om a single source. Each piece had a float surface area of approximately 25 m2. Each of the samples was mounted, float side up, on an aluminum SEM stub with double-sided carbon tape. The samples were then analyzed by automated SEM- EDS method, using two different sized areas of analysis. First, each of the seven samples was analyzed in spot mode using a single point as the area of analysis. Then, the same seven samples were analyzed using a small area across which the electron beam is scanned or "rastered". This area, called a reduced raster, measured 2.25 x 10.2 um. Upon quantification of the elements tin, sodium, magnesium, aluminum, potassium, and calcium, elemental ratios were calculated. The average for each elemental ratio, along with the corresponding standard deviation, was calculated for each 20 sample. The elemental ratio averages for the first sample were compared to the standard deviations from the ratio averages of the other six samples in order to determine if the first average fell within one, two, three, or greater than three standard deviations from the average of the second sample. This comparison was performed with each of the six ratios for each of the seven samples being compared to the standard deviation of the other six samples, which resulted in 252 comparisons. These comparisons were performed for the data obtained using the reduced raster analysis, and then for the analysis done in spot mode. This procedure was repeated with fourteen more samples (two sets of seven samples from each of two separate sources) resulting in 504 more comparisons of data obtained using spot mode, and 504 comparisons of data obtained using a reduced raster. According to the theory of the normal curve, 99% of the average ratios for a sample should fall within 3 standard deviations of the average ratio of another sample obtained from the same source.”ii The results of the comparison of spot mode versus reduced raster mode (Table 4.4) indicate that for two out of the three sources examined, the distribution of elemental ratios more closely approximates a normal distribution when the analysis occurs over a reduced raster area, rather than at a single point. % Within 3 Std Dev. Dodge Chrysler Mercury Spot Mode 90.87 92.86 97.62 Reduced Raster 92.46 95.24 95.4 Table 4.4: Comparison of Spot Mode vs. Reduced Raster Analysis of Glass from Three Sources. Therefore, in the analysis of glass by SEM-EDS it is more precise to analyze a small area of the sample, rather than just a single point. The other parameter for analysis that must be examined is the number of iterations of the analysis that must be performed in order to assure a precise result. While 21 the requirement of precision must be satisfied, it must also be balanced with limitations of time. Although performing hundreds of repeat measurements on each sample would demonstrate the reliability of the measurements, these tests would take days to complete under ideal circumstances. While precision is the goal, practicality is the guide. Under this principle, fourteen samples of glass from different sources were examined by SEM-EDS under a low vacuum, and using a reduced raster analysis. The samples were prepared by washing each with acetone in a sonic bath, and then mounting each one, float side up, on an aluminum stub with carbon tape. The samples were scanned for 100 live seconds each, and then alternately rescanned twice more, for a total of 3 iterations. For each sample, elemental ratios were calculated for each of the three iterations. Then, for each of the six ratios, the average of the three iterations was calculated along with the corresponding standard deviation. Finally, the average standard deviation for each ratio was calculated. The procedure was then repeated with the same samples, only the samples were alternately scanned for a total of five iterations. The same calculations were performed, and the results compared in Table 4.5. Standard Deviation as Percent of the Average Ratio ,1); ix Na/Al 16.18 12.42 Mg/Al 15.53 1 1.28 Na/Mg 11.36 3.50 Ca/Na 11.47 2.79 Ca/K 27.87 15.66 Sn/Na 30.81 19.46 Total 113.22 65.11 Table 4.5: Comparison between Three Iterations and Five Iterations of Each Sample These results indicate that analysis done with five iterations shows a lower average standard deviation for all elemental ratios. F urtherrnore, when the average 22 standard deviations are totaled, the analysis done with three iterations shows a higher total than that done with five iterations. As standard deviation is a measure of precision, these results indicate that precision of analysis is improved when five iterations are performed. Therefore, analysis done with five iterations has an overall greater precision than does an analysis done with three iterations. As increasing the number of iterations from three to five adds only approximately 200 seconds per sample to the analysis time, analysis done in five iterations remains practical. Therefore, it is recommended that by this method, samples be analyzed in an alternating manner for a total of five iterations per sample, rather than three. Statistical Model for Inclusion Upon determination of appropriate operating parameters, a statistical model for inclusion was developed using the designated parameters. This model establishes a statistical range applicable to each sample so that when comparing two samples of glass, the analyst will be able to detemrine if the results are inclusive (the samples could have come from the same source) or exclusive (the samples did not come from the same source). The inclusion or exclusion of a sample is based on a statistical range rather than an absolute number because of random error. Random error is introduced into every scientific measurement as each measuring device itself has a limit to the reproducibility of its measurements. This results in slightly different elemental concentrations being calculated for different analyses of the same piece of glass. Thus, although the calculated numbers are not exactly the same, they may fall within a range that statistically permits the calculated values to be considered to be consistent. For this reason, a statistical range must be established which will allow the analyst to determine if two samples of glass with different elemental concentrations should be considered to have come from the same source. This particular statistical range has been termed the "statistical model for inclusion" in this study. 23 The statistical model for inclusion was established based on the normal curve described earlier. The normal curve predicts that repeated measurements of a sample, taken under the same conditions will yield results that cluster around some central value. The normal curve predicts that 99.7% of the measurements taken for a particular sample will fall within 3 standard deviations from the mean, or central value. Thus, the first part of the statistical model for inclusion says the average elemental ratio of the questioned sample must fall within 3 standard deviations from the mean of the known sample. However, the normal curve is a theoretical distribution, and so an additional factor of 5% was included to account for natural sample and instrumental irregularities. With this consideration, the statistical model for inclusion was stated as follows: if the average elemental ratio of the questioned sample falls within the greater of the range of plus-or- minus three standard deviations or 5% of the average ratio of the known sample, then the samples are concluded to have possibly come from the same source. To test the statistical model for inclusion, seven glass samples were taken from each of four separate sources. Each set of seven samples was analyzed by the automated method previously developed. The elemental ratios described in Table 1.1 were calculated, and then compared. The elemental ratio averages were compared in the following manner. The average of the first elemental ratio, Na/Al, for the first sample was compared to the average Na/Al ratio for the second sample from the same source. The object of the comparison was to determine if the average elemental ratio of the first sample would fall within the greater of the range of plus-or-minus three standard deviations or 5% of the average ratio of the second sample. This comparison was carried out for all ratios of sample 1 being compared to the statistical ranges for samples 2 through 7. Then, the comparison was performed between the elemental ratios of sample 2 and the statistical range for the ratios of the other 6 samples (1,3,4,5,6,7). This was carried out so that each elemental ratio average for each 24 sample was compared against the statistical range for every other corresponding elemental ratio average for every other sample from the same source. The procedure was repeated for each of the 7 samples originating from each of the 4 sources. This resulted in 252 comparisons for each source. Each comparison resulted in a designation of "included" if the elemental ratio average fell within the range of 3 standard deviations or 5% of the elemental ratio average it was being compared against. Conversely, if the average did not fall within the prescribed range, it was given a designation of "excluded". A summary of these results is given in Appendix V. Of all 1008 comparisons, 96% were "included" while 4% were "excluded" (Table 4.6). Source 1 2 3 4 Total Percent cluded 240 238 240 25 1 969 96.1% Excluded 12 14 12 1 39 3.9% Table 4.6: Number and Percent of Same Source Automotive Glass Included and Excluded Based on Statistical Model for Inclusion. As described earlier, in a standard normal distribution, 99% of all results will fall within 3 standard deviations of the average. In this study, it was shown that 96% of all results fell within the larger of 3 standard deviations or 5% of the average. The range of three standard deviations is then appropriate. If the statistical range had been narrowed to two standard deviations, a larger portion of the measurements of the same sample would have been falsely excluded. Similarly, if the range had been widened to include results that fell within 4 standard deviations from the average, a number of samples from different sources would have been falsely included. The statistical model using a range of three standard deviations or 5% of the average as a basis for inclusion limits the extent of false inclusions and false exclusions. Thus, this model was accepted as an appropriate statistical range for inclusion and exclusion. 25 Therefore, the statistical model for inclusion establishes that for all ratios compared, if the average of the five measurements of elemental ratios of the questioned glass fit within the greater of a three standard deviation or 5% range of the five measurements of the known glass, it can be concluded that the samples could have originated from a common source. Conversely, if the average elemental ratios of the questioned glass do not fall within the range of three standard deviations or 5% of the average of the known, it is concluded that the samples could not have originated fiom the same source. If only one or two of the six ratios fall outside the prescribed range, the samples must be reanalyzed before exclusion. If, after reanalysis, one or two ratios still fall outside of the prescribed range, the result is inconclusive. That is, it can neither be said that the questioned sample originated from the known, nor can it be said that it did not originate fi'om the known. The result in this case must be inconclusive because the elemental concentration of the questioned falls outside the prescribed range of the known, but within the range of variation within the known. This variation was demonstrated above as 4% of known same source elemental ratios fell outside the range demonstrated by other samples from the same source. Using these criteria, upon reanalysis of the samples used to establish the statistical model for inclusion, no sample was falsely excluded (Table 4.7). A summary of the results can be found in Appendix V. Number Percent eluded 135 80.4% Excluded 0 0.0% Inconclusive 33 19.6% Total 168 100.0% Table 4.7: Number and Percent of Same Source Samples Included, Excluded or Deemed Inconclusive Using the Statistical Model for Inclusion. 26 Therefore, based on data obtained from elemental analysis and by using the statistical model established above, the analyst has the capability to determine if a questioned piece of glass could have originated from a known source or not. Summary A method for the elemental analysis of glass was established. This method requires that the samples be analyzed under a low vacuum of 10 Pa. Each sample was analyzed five separate times using a reduced raster (2.25 x 10.2 um) for 100 live seconds each time. The elements quantitated were tin, sodium, magnesium, aluminum, potassium, and calcium. The elemental concentrations were paired in the following ratios for each of the five iterations: Sn/Na, Na/Al, Mg/Al, Na/Mg, Ca/Na, Ca/K. The average of each ratio (taken over the five iterations per sample) was calculated and the standard deviation for each average was recorded. Comparison between the elemental concentrations of different samples was performed using the statistical model of inclusion. Using this model, if the average of the five measurements of elemental ratios of the questioned glass fit within the greater of a three standard deviation or 5% range of the five measurements of the known glass, it was concluded that the samples could have originated from a common source. However, if the elemental ratios of the questioned glass fall outside of the statistical range for the known, the questioned sample is excluded as originating from the same source as the known. Using this method and the statistical model, an analysis of same source automotive glass resulted in 96% of the comparisons yielding an inclusive conclusion. Examination of the Effect of Sample Tilt Angle An important component to consider in the development of this methodology was if the shape of the sample could have any effect on the accuracy of the analysis. Forensic glass samples arise from many different sources and scenarios and so do not demonstrate 27 uniformity in their shape or surface characteristics. An important characteristic to consider when conducting SEM-EDS analysis is the tilt angle of the surface of the sample. The tilt angle of the surface of a sample may range from 0° (perfectly flat) to -1— k Flat sanrple Sloped sample highly sloped (Fig. 4.1). Figure 4.1: The tilt angle of the surface of a sample may range from perfectly flat to highly sloped. The tilt angle of the surface of the sample is an important consideration in SEM- EDS analysis because the quantification program assumes that the sample is flat and smooth (see Appendix ID). A sample that is indeed flat and smooth, satisfies this assumption and quantification is performed accurately. However, if a sample is tilted or has rugged topography the assumption made by the quantification is not correct and may lead to inaccurate quantification results. To examine this effect and to determine if the inaccuracy in the quantification of elements from tilted samples affects their inclusion in the statistical model, one sample was examined at tilt angles ranging from 0° to 5°. Procedure A sample of glass with parallel sides was mounted float side up on an aluminum SEM stub. As the sample had parallel sides, it was assured to have been mounted so that the surface for analysis was parallel to the face of the aluminum stub. In other words, the sample was assured to have been mounted at a tilt angle of 0°. The sample was then analyzed under low vacuum, with the prescribed elements being 28 angl tilt a mg: mme vam' comp Ckme deter-n suitab; With 0 mmon Summ. Van-able Ulster ar SPECifiC inCIUSior another 5 quantitated. This analysis was repeated for a total of five iterations. The appropriate elemental ratios and standard deviations were calculated. The stage of the SEM, which holds the sample, was then mechanically tilted to an angle of 1°, effectively changing the sample tilt angle from 0° to 1°. The elemental analysis was completed as before, with five iterations and the calculation of elemental ratio averages and standard deviations. The procedure was repeated with the stage being tilted to 2°, 3°, 4°, and 5°, with all analyses being conducted on the same piece of glass. Upon completion of the analyses, the results from the samples analyzed at tilt angles of 1°, 2°, 3°, 4°, and 5° were compared to the results obtained from the analysis at tilt angle 0°. Using the statistical model of inclusion, the analyses performed at a tilt angle of 1° or greater resulted in the sample being excluded as having come from the same source as the sample analyzed as 0°. However, as the samples analyzed at the varying tilt angles and the sample analyzed at 0° were one and the same, it is evident that comparison of samples with a tilt angle difference of 1° will result in inaccurate elemental quantification and inaccurate exclusion of the sample. Therefore, it was determined that only samples that can be mounted and analyzed at a tilt angle of 0° are suitable for analysis by this method. As it would be difficult to mount glass fragments with only one flat side to a tilt angle of 0° with any measure of certainty, it is concluded that only samples with two parallel sides are permitted to be analyzed by this method. Summary The elemental analysis of glass may be easily and accurately accomplished by variable pressure SEM-EDS. The method herein established provides for the reduced raster analysis of glass samples under a low vacuum with the quantification of six specific elements. The six elements are ratioed and under the statistical model of inclusion the average ratio of one sample may be compared to the statistical range for another sample to determine if the two samples could have originated fi‘om the same 29 source. This method must be performed on glass samples that demonstrate two parallel sides, one of which must be the float side. Using this method, forensic samples may be accurately analyzed and questioned samples may be compared to known samples to determine common origin. While elemental analysis demonstrates a greater ability to distinguish between similar samples, it is not a replacement for the traditional optical analysis of glass. Rather, it is a supplement used to distinguish between glasses that cannot be distinguished by optical and physical properties alone. This supplementary role was investigated and the results were demonstrative of the necessity and utility of elemental analysis as a component of the analytical scheme in forensic cases. Application of Variable Pressure SEM-EDS to Glass Analysis Upon the development of suitable operating parameters for the SEM-EDS system, this method was applied to the analysis of tempered automotive glass samples. The elemental data obtained by this method for each sample was used to distinguish between samples that were indistinguishable by refractive index alone. Procedure Fifty samples of tempered automotive glass were collected, each from a different source. Refractive index measurements were taken for each sample. The refractive index was measured by way of Emmons double variation method. A small piece of glass was crushed into fine pieces using a mortar and pestle. These tiny pieces were transferred to a clean microscope slide and a drop of Dow Corning 810 Oil was applied to cover the glass. A cover slip was applied over the sample, and the slide was placed inside the stage of a Mettler FPS hot stage microscope. A piece of glass was located and situated in the center of the field of view. The temperature of the hot stage was set so that the Becke line around the sample disappeared at, or around, a wavelength 30 of 610 nm. The monochromator was returned to a wavelength of less than 310 nm and then rotated through the spectrum, from 310 nm, to the wavelength at which the Becke line disappeared. This wavelength was recorded. Without changing the temperature of the hot stage, this procedure was repeated for a total of 6 iterations. The temperature of the hot stage was then increased by one degree Celsius. The measurement of the wavelength at which the Becke line disappeared was again performed with six iterations. The procedure was repeated for ten temperatures, the last temperature being nine degrees above the starting temperature. For example, if the starting temperature was 62 degrees, the final temperature would have been 71 degrees. The data was then entered into a computerized calculation template that calculated the dispersion and the refractive index of the glass at 656 nm, 589 nm, and 486 nm (C-, D-, and F - lines respectively). A graph of wavelength versus temperature was also plotted, which, if not linear prompted the re-analysis of the sample. This procedure was repeated for each of the fifty samples of glass collected from different sources. The refractive indices were recorded and each compared to those of the other 49 samples, yielding a total of 2450 comparisons. The criteria for inclusion used by the Michigan State Police in comparing refiactive index measurements were used as the criteria for comparison in this study. These criteria state that a sample is to be excluded if the variation between its refractive index and that of the known sample is greater than 0.0001 at 589 nm, or 0.0002 at 486 nm or 656 nm, or if the difference in dispersion is greater than 2.0000. Using these criteria, the refractive indices of all 50 samples were compared. Of the 2450 comparisons, 186 were inclusive. That is, for these samples there was little or no difference in refractive index measurements between the two samples being compared. These 186 comparisons resulted in a false inclusion, as each of the samples compared originally came from a different source. Therefore, in comparing refractive index alone, a false inclusion resulted in 7.6% of the comparisons made. 31 Elemental Analysis All 50 samples were also analyzed by SEM-EDS. 1092 pair-wise comparisons were made resulting in 7.6% being falsely included when SEM-EDS was used without regard to refractive index (Table 4.9). SEM-EDS was also performed on those 186 samples not distinguished by refractive index, and the elemental data was compared using the statistical model for inclusion. 131 of these comparisons resulted in exclusion, 20 resulted in inclusion and 35 yielded an inconclusive result. Therefore, in the cases that could not be discriminated by refractive index, 10.8% of the comparisons made resulted in a false inclusion after SEM-EDS analysis. Overall Results When the elemental analysis comparisons were combined with the results of the refractive index measurements a marked improvement in discriminating power was observed. Of the 2450 comparisons made between samples from different sources, 97.8% of the samples could be distinguished when elemental analysis was used to distinguish between samples with similar refi'active indices. Using only refractive index, a false inclusion resulted in 7.8% of the cases, while combining refractive index and elemental analysis resulted in a false inclusion in less than 1% of all cases (Table 4.8). Refractive Index Elemental Analysis Elemental Analysisi Combined Inconclusive 0 0 35 18.8 182 16.7 35 1.4 (Same R1) (R1 not considered) # % # % # % # % Inclusive 186 7.6 20 10.8 83 7.6 20 0.8 Exclusive 2264 92.4 131 70.4 827 75.7 2395 97.8 Total 2450 100 186 100 1092 100 2450 100 Table 4.8: Summary of Data 32 Summary In the manufacturing process, the quality of glass is often checked by controlling the refractive index of the product. As such, it is not unusual to encounter glasses from different sources that possess similar or indistinguishable refractive indices. This has been demonstrated by this study. When such uniformity is encountered in the forensic laboratory a second means of distinguishing samples from different sources must be utilized in order to reach an acceptable conclusion regarding the sources of the samples. The use of SEM-EDS to distinguish between glasses fi'om different sources with indistinguishable refractive indices was investigated. The investigation was preceded by development of suitable SEM-EDS operating parameters and identification of sample limitations. Upon implementation of the appropriate analytical method, the refractive indices of glasses from 50 different sources were compared. In the analysis of the 50 samples of tempered automotive glass, the refractive index of each sample was measured and compared to the refractive index of each of the other 49 samples. By comparing only the refractive indices of the glass samples, 7.6% of the comparisons were inclusive. That is, although the samples originated from different sources, they were indistinguishable when comparison was based only on the measurement of their respective refractive indices. Similarly, when analyzed by SEM- EDS without regard to refractive index, 7.6% were falsely included. However, when the results of the refractive index comparisons were coupled with the results of the elemental analysis, only 0.8% of the comparisons resulted in a false inclusion. 33 Chapter 5: Conclusions and Discussion This study developed a method by which the elemental analysis of glass may be accomplished by variable pressure SEM-EDS. The method was established through repeat analyses and statistical interpretation of the accumulated data to determine the operating parameters that yielded the best precision of results. When combined with refractive index measurement, the utility of this SEM-EDS method was then demonstrated. Conclusions It was first concluded that variable pressure SEM-EDS is' applicable to the analysis of glass. The analysis of glass under a low vacuum of 10 Pa resulted in greater precision in repeat analyses than both the traditional high vacuum analysis (0.01 Pa) and analysis after coating the sample with carbon. The analysis performed under a low vacuum yielded greatest precision when samples were scanned with a reduced raster of 2.25 x 10.2 um2 in five iterations. Also, it was concluded that the tilt angle of the sample affects the accuracy of the elemental data. It was determined that in order to accurately compare two samples of glass, they must both be mounted to a tilt angle of 0°. As it is difficult to mount jagged glass fragments to a tilt angle of 0° with any degree of certainty, only those samples with two parallel sides are suitable for analysis by this method. Using these parameters, it was concluded that an appropriate statistical model for inclusion requires the calculation of elemental ratios (Sn/N a, Na/Mg, Mg/Al, Na/Al, Ca/Na, Ca/K) and the comparison of the average of each ratio from the questioned sample to the greater of the range of three standard deviations or 5% of the average ratio of the known sample. It was determined that if the questioned average ratio fell within the prescribed statistical range, the result was inclusive. 34 Using the method developed by this study, 50 samples of tempered automotive glass were examined. Refractive index measurements were performed on each sample, and the results were compared. Those samples that were indistinguishable by refractive index were compared based on the statistical model for inclusion developed for the SEM- EDS method. These comparisons demonstrated the value of SEM-EDS in the analysis of glass. It was demonstrated that if refractive index measurement was the sole comparison criterion, 7.6% of all comparisons resulted in a false inclusion. Similarly, if elemental analysis data were compared without regard to refractive index measurement, 7.6% of all comparisons resulted in a false inclusion. However, when elemental analysis was used in tandem with the measurement of refiactive index, only 0.8% of all comparisons were falsely included. Therefore, it is concluded that by applying variable pressure SEM-EDS, the forensic scientist is better able to distinguish samples of glass that are indistinguishable by refractive index alone. Discussion As technology advances and traditional methodology is replaced, the capabilities of the scientist are often increased. However, in this study, there proved to be little advantage in completely replacing the traditional refi'active index measurement with SEM-EDS in the forensic analysis of glass. Under the parameters established, SEM-EDS by itself did not demonstrate an increase in discriminating power over that of refractive index measurement. However, the combination of the two techniques resulted in a dramatic increase in discriminating power over either technique when used alone (Table 5.1). 35 Discriminating Power Population # Discrinrinated RI alone 0.924 2450 2264 SEM-EDS alone 0.909 910 827 R1 & SEM-EDS 0.992 2414 2395 Table 5.1. Comparison of the Discriminating Power of Refractive Index measurement and SEM-EDS when used alone and in combination. Thus, elemental analysis by this SEM-EDS method does not serve to replace traditional refractive index measurement of glass samples in forensic cases. Rather, this SEM-EDS method plays a supplementary role by providing the ability to analytically distinguish between samples of glass that are indistinguishable by refi'active index measurement alone. In this supplementary role, elemental analysis by SEM-EDS decreased the number of false inclusions. A false inclusion results when the analysis concludes an unknown sample could have arisen from known source, when in fact it did not. For example, a window in a suspect's car may be falsely included as a source of glass found on the victim. This study demonstrated that when analyzed by refractive index alone, a false inclusion resulted in 7.6% of all comparisons. However, when these glass samples were compared using SEM-EDS and the statistical model for inclusion, less than 1% were falsely included. Therefore, by supplementing refractive index measurement with elemental analysis by SEM-EDS, the number of false inclusions was greatly reduced. For this analytical scheme, elemental analysis by SEM-EDS is logically performed subsequent to refractive index measurement. However, with automated techniques such as this method, elemental analysis may serve as an efficient screening procedure. 36 C01 suit OPP (16ml ma) geoni berm Flltui innru] mmds MdSE SOUICe. ’egardi. In cases with multiple known and unknown samples, refractive index measurement of each sample may be tedious and time consuming. In such a case, automated elemental analysis may allow efficient examination of the many samples by eliminating samples with exclusive elemental comparisons from further analytical comparison. In this way, a large number of samples may reduced to a smaller portion that may then be analyzed by refractive index. However, this SEM-EDS method is not without certain limitations. Of primary concern is that fact that sample geometry plays an important role in elemental analysis, and may be prohibitive in certain forensic cases. As demonstrated by this study, only those samples with two parallel sides are suitable for analysis. In general, this requirement restricts analysis to window glass as opposed to container glass. Furthermore, fragments of window glass do not always demonstrate parallel sides, and so the proportion of samples for which this SEM-EDS analysis is applicable is greatly limited. While this SEM-EDS method is applicable to only samples with certain geometries, it has proven to increase the ability of the forensic scientist to distinguish between samples of glass that are indistinguishable by refractive index alone. Future Research Upon conclusion of this study, two additional areas of future research are suggested: research furthering the SEM-EDS method developed and research into other instrumental methods for elemental analysis of glass. The SEM-EDS method developed herein might benefit from examination in a blind study. Such a study would involve analysis of multiple samples by refi'active index and SEM-EDS to determine which samples could have originated from a common source. In such a blind study, the analyst would not possess any knowledge beforehand regarding the actual sources of the samples. The results of the analysis could then be 37 interpreted without bias, and compared to determine if the correct associations had been made. The current method should also be investigated to determine if it is usefirl for the analysis of other types of flat glass. At present, only float glass has been analyzed by this method. Two other types of flat glass, rolled- and sheet- glass, should be subjected to this method. Rolled glass is compressed between two rotating rollers as it leaves the melting fumace and so would not demonstrate the tin fluorescence or other characteristics of float glassmii Similarly, sheet glass would not demonstrate float characteristics as it is prepared by drawing a sheet of glass out of a bath of molten glassm" As both rolled- and sheet- glass have not yet been analyzed by this method, it would be beneficial to determine if the method requires modification for analysis of non-float glasses. Also, the implementation of a third technique might be studied in future research. This third technique would be used subsequent to refractive index measurement and elemental analysis in order to further differentiate those samples that are not discriminated by the methods of the current study. Emission spectroscopy has been previously linked to a refractive index - SEM-EDS method,"xv no third technique has been investigated in conjunction with the variable pressure SEM-EDS procedure developed in this study. By adding a third instrumental technique to the method, the number of inconclusive results and false inclusions could be reduced even further. However, the major limitation of the current study is the requirement that the sample must have a tilt angle of 0° (or parallel sides). The most beneficial research related to this SEM-EDS method would be the investigation of tilt angle measurement and correction for samples that do not demonstrate parallel sides. As this sample requirement is severely limiting, successfirl research in this area would greatly increase the applicability of the current SEM-EDS technique. 38 Beyond SEM-EDS Since SEM-EDS methods are limited by the requirement of flat samples, other instrumental techniques must be investigated. Recent research has focussed on inductively coupled plasma mass spectrometry (ICP-MS) consequently making ICP-MS the fastest growing trace element techniquemi The popularity of ICP-MS is primarily based upon the advantages of increased sensitivity and the ability to analyze for multiple elements. The ICP-MS requires a liquid sample, which is converted into a fine aerosol spray. A plasma is formed when argon gas in a magnetic field is sparked with a high voltage source of electrons. The plasma is then used to generate positive ions from the sample. The ions are introduced into the mass spectrometer and separated based on their mass to charge ratio (m/z). ICP-MS has been used to analyze small samples of glass (100 pg) but the glass must be dissolved in a series of acids prior to introduction into the ICP-MS.""Vii More recently however, solid samples have been able to be analyzed without having to undergo acid digestion. In a process called laser ablation, a laser is used to vaporize an area on the surface of the sample. The particles that result from the laser ablation are then swept into the ICP-MS. This method has distinct advantages. First, the method can be used to detect ultra trace levels directly in a solid without requiring acid digestion. Secondly, any solid may be used, irrespective of its electrical conductivity, size, shape or surface topography. As shape and surface topography are limiting factors for SEM-EDS analysis of glass, future research should logically attempt to eliminate these restrictions. In this way laser ablation ICP-MS might be a promising avenue of future research. 39 Appendices: I. II. III. IV. VI. VII. Glossary Elemental Data: high vacuum, low vacuum, and sputter coated samples Elemental Data: Tilt Angle Effects Summary of Elemental Ratio Comparisons in the Establishing of a Statistical Model for Inclusion Refractive Index Comparisons 186 Elemental Comparisons of Samples not Distinguished by Refractive Index Summary Data for Refractive Index and Elemental Analysis Comparisons 40 Appendix I Glossary Becke Line The bright halo that outlines a transparent particle immersed in a liquid of different refractive index. Discriminating Power The probability that two distinct samples, taken at random from the population of interest, would be discriminated. Dispersion The relationship between the refractive indices of a substance at different wavelengths. For glass, dispersion is represented by the relationship V=(Nd - 1)/(Nf-Nc). Electron A negatively charged subatomic particle. Hot Stage Microscope A microscope with an enclosed, oven-like sample holder that allows the sample to be heated to precise temperatures. Iteration A repetition of a measurement or procedure. Monochromator An instrument that selectively allows only one wavelength (color) of light to be emitted. Physical Properties Properties of a substance that can be measured and observed without changing the composition of the substance. For example, color, density, and thickness are physical properties. 41 Te Optical Properties Those physical properties specifically associated with light. For example, refi'active index and dispersion are optical properties. Refi'active Index The ratio of the speed of light traveling in a vacuum to the speed of light traveling in a transparent medium such as glass. Tempered Glass Glass that has been thermally or chemically toughened to resist breakage. Tempered glass is most often found in side and rear windows of automobiles, shower stalls, and doors to business places. 42 Appendix II Elemental Data: high vacuum, low vacuum, and sputter coated samples 43 III .CLEFFDNLLNM. Sample uzuki Esteem 1 Ford Probe Fonda Accord RI - C-line 1.5162 1.5175 1.5162 R1 - D-line 1.5188 1.5200 1.5188 R1 - F-line 1.5257 1.5267 1.5256 LOW VAC Na/Al 9.107 0.3855 6.207 0.7520 3.352 0.1117 Mg/Al 3.135 0.1418 2.002 0.1715 1.243 0.0566 Na/Mg 2.905 0.0476 3.093 0.1314 9.561 0.1286 Ca/Na 1.275 0.0185 1.211 0.0223 1.085 0.0289 Ca/K 30.036 2.9976 18.831 1.2337 6.891 0.6884 Sn/Na 0.036 0.0051 0.036 0.0059 0.045 0.0089 HI VAC Na/Al 34.453 8.0338 10.012 0.8174 6.400 0.9989 Mg/Al 8.752 3.0053 2.423 0.1353 1.935 0.0994 Na/Mg 4.217 1.3547 4.132 0.2557 9.982 0.3870 Ca/Na 0.261 0.0422 0.146 0.0154 0.196 0.0404 Ca/K 49.379 27.7909 11.125 2.3856 5.263 0.9946 Sn/Na 0.000 0.0333 0.084 0.0257 0.087 0.0197 SPUTTER CT. Na/Al 10.880 0.5249 5.956 0.3231 3.550 0.0403 Mg/Al 3.794 0.1114 1.977 0.0808 1.369 0.0259 Na/Mg 2.868 0.1160 3.013 0.1180 9.468 0.0352 Ca/Na 1.348 0.0358 1.255 0.0339 1.149 0.0229 Ca/K 49.756 11.0820 19.642 0.8619 7.205 0.3235 Sn/Na 0.027 0.0090 0.019 0.0034 0.020 0.0053 Appendix Table 2.1: Elemental Data for high vacuum, low vacuum and sputter coated samples. Sample b8 Pontiac Gd Prix b8 Toyota Celica b0 Acura Legend RI-C-line 1.5164 1.5174 1.5137 R1 - D-line 1.5189 1.5202 1.5163 R1 - F-line 1.5257 1.5275 1.5233 LOW VAC Na/Al 5.927 3.3842 3.784 0.2052 9.279 0.7270 Mg/Al 2.011 1.1154 1.340 0.0000 3.101 0.2091 Na/Mg 2.926 0.1434 2.823 0.1131 2.991 0.0517 Ca/Na 1.152 0.9815 1.295 0.0620 1.162 1.0159 Ca/K 22.191 13.4472 6.507 0.6687 37.930 5.0336 Sn/Na 0.052 0.0086 0.034 0.0190 0.044 0.0016 HI VAC Na/Al 8.636 3.3073 6.331 0.2687 14.196 1.5225 Mg/Al 2.903 0. 7685 1.713 0.0636 4.253 0.6356 Na/Mg 2.949 0.6072 3.698 0.1468 3.358 0.2055 Ca/Na 0.656 1.2470 0.259 0.0640 0.411 1.5926 Ca/K 20.301 7.4152 5.016 0.6170 36.434 11.1678 Sn/Na 0.054 0.0109 0.056 0.0073 0.054 0.0138 SPUTTER CT. Na/Al 6.171 3.1422 3.762 0.7843 10.513 2.1192 Mg/Al 2.218 0.9304 1.307 0.2315 3.586 0.6054 Na/Mg 2.727 0.3079 2.866 0.1246 2.918 0.1127 Ca/Na 1.707 0.6411 1.364 0.0205 1.296 0.8667 Ca/K 23.991 14.6425 7.000 0.2695 46.735 12.8838 Sn/Na 0.033 0.0112 0.015 0.0024 0.022 0. 0109 Appendix Table 2.1 continued: Elemental Data for high vacuum, low vacuum and sputter coated samples. 45 Sample 1 Mercu Sable 4 Ford Escort 1 Dad e Shadow RI-C-line 1.5163 1.5168 1.5164 RI-D-line 1.5189 1.5195 1.5190 R1 - F-line 1.5260 1.5267 1.5259 LOW VAC Na/Al 9.168 0.5913 8.950 0.4842 14.017 1.3001 Mg/Al 2.754 0.1630 2.585 0.3695 4.207 0.4585 Na/Mg 2.904 0.0867 3.518 0.5249 3.337 0.1260 Ca/Na 1.262 0.0312 0.600 0.0390 0.654 0.0399 Ca/K 33.281 5.4060 17.568 6.6721 32.518 6.1133 Sn/Na 0.039 0.0075 0.034 0.0107 0.042 0.0019 HIVAC Na/Al 29.826 9.8295 14.954 3.74965 39.773 16.5655 Mg/Al 7.167 2.4469 3.313 0.76215 9.376 3.8568 Na/Mg 3.937 0.2483 4.499 0.24306 4.240 0.0827 Ca/Na 0.276 0.0339 0.119 0.02786 0.168 0.0222 Ca/K 23.746 11.0057 7.075 5.14342 18.805 6.0878 Sn/Na 0.059 0.0210 0.000 0.01329 0.059 0.0072 SPUTTER CT. Na/Al 11.102 1.2104 5.944 0.2540 11.063 1.1855 Mg/Al 3.425 0.3298 2.129 0.1068 3.705 0.3251 Na/Mg 2.773 0.0762 2.793 0.0480 2.982 0.0733 Ca/Na 1.321 0.0602 1.472 0.0209 1.386 0.0345 Ca/K 51.854 12.2277 25.395 3.1009 48.574 6.0323 Sn/Na 0.017 0.0137 0.014 0.0042 0.020 0.0019 Appendix Table 2.1 continued: Elemental Data for high vacuum, low vacuum and sputter coated samples. 46 i .|.Il.1|l .t ,t .Ccfi R_..L\.\\l.\\lCC al C Sample b0 Datsun 210' Mid? Ford Taurus R1 - C-line 1.5145 1.5170 R1 - D-line 1.5170 1.5198 R1 - F-line 1.5237 1.5271 LOW VAC Na/Al 5.780 3.3523 11.539 1.5068 Mg/Al 1.808 0.7279 3.833 0.4410 Na/Mg 3.070 0.4194 9.780 0.0931 Ca/Na 0.643 1.5441 0.742 0.0293 Ca/K 5.285 0.4123 42.942 13.6361 Sn/Na 0.052 0.0191 0.045 0.0115 HI VAC Na/Al 7.801 2.6892 23.596 5.3467 Mg/Al 2.068 0.6075 6.216 1.4059 Na/Mg 3.739 0.1726 10.435 0.0591 Ca/Na 0.237 2.0386 0.207 0.0140 Ca/K 4.127 0.5431 22.037 9.0185 Sn/Na 0.109 0.0187 0.063 0.0141 SPUTTER CT. Na/Al 5.025 3.8114 8.586 1.6420 Mg/Al 1.849 1.2230 3.132 0.5222 Na/Mg 2.629 0.1780 9.584 0.1033 Ca/Na 1.385 0.7663 1.583 0.1102 Ca/K 12.101 14.1318 71.369 42.8497 Sn/Na 0.021 0.0035 0.018 0.0048 Appendix Table 2.1 continued: Elemental Data for high vacuum, low vacuum and sputter coated samples. 47 Sample ord Tern 0 GL 9 Chrysler B0 Datsun 210, driv. Rear , RI - C-line 1.5166 1.5162 1.5138 R1 - D-line 1.5193 1.5188 1.5163 R1 - F-line 1.5265 1.5256 1.5231 LOW VAC Na/Al 6.571 0.3113 14.276 0.8490 4.542 0.1416 Mg/Al 2.080 0.0000 4.415 0.1476 1.866 0.0450 Na/Mg 3.162 0.1238 3.231 0.0909 2.904 0.1132 Ca/Na 0.704 0. 0399 0.726 1.3865 0.581 0.0270 Ca/K 18.607 0. 7214 63.822 58.221] 5.443 0.3814 Sn/Na 0.042 0.0022 0.040 0.0030 0.046 0.0044 HI VAC Na/Al 10.804 1.1509 16.773 7.0892 7.551 0.5507 Mg/Al 2.729 0.2414 4.601 1.5457 2.760 0.1501 Na/Mg 3.955 0.1235 3.565 0.3388 3.623 0.1003 Ca/Na 0.159 0.03 78 0.237 1.6849 0.094 0.0127 Ca/K 12.249 6.8740 31.018 6.5843 3.087 0.5402 Sn/Na 0.063 0.0068 0.087 0.0261 0.098 0.0153 SPUTTER CT. Na/Al 5.665 0.4386 10.923 0. 7735 3.494 0.05 72 Mg/Al 1.957 0.1199 3.773 0.2541 1.767 0.0418 Na/Mg 2.894 0.0825 2.894 0.0425 2.520 0.0367 Ca/Na 1.440 0.0407 1.419 0.7922 1.342 0.0331 Ca/K 23.238 1.7337 59.869 31.3815 5.729 0.2446 Sn/Na 0.018 0.0012 0.016 0.0031 0.022 0.0033 Appendix Table 2.1 continued: Elemental Data for high vacuum, low vacuum and sputter coated samples. 48 Appendix III: Elemental Data: Tilt Angle Effects Because of complex interactions between components of a sample, a correction factor must be applied to the apparent elemental concentration in order to determine the true concentration. One part of the correction factor is the absorbanee of x-rays by components of the sample. The quantification program assumes the sample is flat, and so correction is made for x-ray absorbanee upon this assumption. However, when the sample is tilted, more x-rays are blocked or absorbed creating an additional absorption factor. The quantification program does not recognize additional absorption factors and so quantification in this case would be performed inaccurately. The following data demonstrate this effect. 49 080m 2?... as ”33 5585 ”3 2.3 288%. ”Ease cages 32 .o 323 mass Sod 2: 2. 826 286 2: .o «25 03.5.06 cameos 03.3: $8.3 $2.2 macs: $3.3 $2.2. ENE 33% 030 05206 ceases 885 $33 236 sad 83s gas 2% ~86 azao cameos cameos to?“ £80 £86 2 .m 38.... 4:3 086 2 2 wzaz cameos cameos ~82 _ 82 R :6 83 2%.... ES“ 326 S3 3»: cameos cameos was: 28.x as: 34.2 22.2 3%.: 52 83: Zaz < as m m as < E 2 E 2 2.5 Bo.— mlowgimi g d 0.4.55 033—23 032:2: 5: :6 wmwcd m. m. 66 6 @606 he: _6 N8: .9 6N 66 6 no: .0 «gum 032:2: 032:2: :VNNdE «3666 N N N 6 .N N mm _ .3. evwwéa mwmm.mm “~me 6~ $066 MED 032:2: 030.328 Smad camwd 6~ N 6 6 mead mmaad :366 V6~ 6 6 mmad «ZED 032:2: 032:2: :bmzm $36 6666 .6 hONfi vmom. m E. : ad 366 6 O: : .m wgaz 038—20 032:2: on mvfi woomd ~63. 6 aamé : mamé m _ hhfi 6M6~ 6 wwo:V :(EE 032:2: 032:2: ©5666: Nomvd: ~36 .~ 6mm. 2 sham. m: 366.: : NMMM 6 mags _<\aZ < 0:: m m 0:: < 3: A: 3: 0: 04> 39‘— amflum majoflmfl m 2&an 032:3"0 032:2: @626 cmcod VN N 6 6 oo— 6 he: :6 N8: 6 m: 66 6 me: 6 «2:5 032:2: 032:2: whaaéw momm. : m NEWW vwmdc cvwwém mwmmdm VVKN6~ 39$ MRO 032:2: 032:2: mmoo: :wad N m. N 6 6 wmad mamad 3566 V6 N 6 6 Nmad «ZED 032:2: 032:2: MOMMA amoocm 6X. 6 6 be: .m vmomd vtam N366 O: :.m m§Z 032:2: 032:2: mvwmfi vwhwd N ~66 6 Nwmé :mam.v m : Rum 6M6~ 6 Nwoé 3‘32 033—20 032:2: 6000.2 266.0: 6N66< ohwd: hmacfiu $66.: NMMM 6 macN: 2R2 < 0:: m m 0:: < 3: O: 3: 0_ U<> BOA 010.301...»- wfiam oafiam 50 floutm: 0:22. 5:. “Sun: 3380:”: 625680 :.m 053. 56:09:44. 033:020 032:2: 6: :6 6wh66 6666 .6 666.6 56: :6 N66:.6 6N 66 .6 m6: .6 07:65 032:020 032:2: 636.6mv :N66.66:- N36 .V6N :66.NN: 6vww.va mwmm.mm VVNN6~ $666 MRO 032:8“0 032:020 w :666 an : w6 6N N 6 .6 amw6 M6666 3666 V6 N 6 .6 N666 «ZED 032:2: 032:2: mmmm.m 66666 6666 .6 66N.m Vmomd 1:66 Q66 .6 6: :.m wzxmz 032:2: 032:2: 6:. 66. m 666?. m N66N .6 hhmé :m6mé m : Ru m 6m. 6 N .6 Nw6.v :<\w$: 03:04:020 032:2: V6666: 66bm6: 6~6N.~ mwm.m: BN666: 356.: : :66 .6 M666: :<\mz < 3:: m m: 3:: < 3: o: 3: 0: U<> BOA a a M 295m 032:020 032:2: mm: :6 mmh66 R66 .6 566.6 56: :6 N66: .6 6 N 66 .6 66: .6 023m 032:2: 032:2: 3666:. :66: .mm 6666 6 hNQmm 6vww.va mwmm.mm 6»va 6~ $666 MRO 032:020 032:020 6wN66 Nmmw6 6m N 6 .6 6:66 mm666 3666 V6 N 6 .6 Nm66 mZRU 032:2: 032:020 56v. m tum : . m 66:6 .6 66m.m VN6M. m Vb : 6.N NV66 .6 6: : . m w§Z 032:020 032:2: wwwmfi @6666 6k 3. .6 9%.? Swami m : 55m 66 6 N .6 Nw6.v :<\w$: 032:020 032:2: 65566: 666w: : 6 6N 6 .~ wwaé: 5N666: 366.: : NMMM .6 m66.N: :<\m7: < 0:: m m: 3:: < 3: 0: 3: 0: U<> 301: 80.. 0:. m a .6 fl min—am 51 Appendix IV Summary of Elemental Ratio Comparisons in the Establishing of a Statistical Model for Inclusion Source # Excluded # Included Total Comparisons Chrysler 12 240 252 Dodge 14 238 252 Mercury 1 2 240 252 Toyota 1 25 1 252 Total 39 969 1008 Percent 3.9% 96.1% 100% Reanalysis of Data Under Statistical Model for Inclusion Guidelines Source Excluded Included Inconclusive Chrysler 0 32 10 Dodge 0 3O 12 Mercury 0 32 10 Toyota 0 41 1 Total 0 1 3 5 33 Percent O 80.4% 19.6% Appendix Table 4.1: Summary of Elemental Ratio Comparisons in the Establishing of a Statistical Model for Inclusion. 52 Appendix V Refractive Index Comparisons 53 Sample 94 Ford Escort 91 Dodge Shadow 80 Datsun 210 M Ford Tempo GL C-Line 1.5168 1.5164 1.5145 1.5166 D-Line 1.5195 1.5190 1.5170 1.5193 F-Llne 1.5267 1.5259 1.5237 1.5265 V 52.512 54.412 56.067 52.443 Sample 89 Chrysler 80 Datsun 210 R. 94 Ford Taurus 85 Toyota Corolla C-Line 1.5162 1.5138 1.5170 1.5173 D-Line 1.5188 1.5163 1.5198 1.5199 F-Line 1.5256 1.5231 1.5271 1.5270 55.261 55.585 51.954 53.558 ample Pontiac Gd Prix 86 Buick Century 89 Ford Tempo 88 Pontiac Gr Pr. C-Line 1.5168 1.5188 1.5161 1.5164 ED-Line 1.5192 1.5125 1.5188 1.5189 F-Line 1.5259 1.5284 1.5260 1.5257 V 56.728 54.436 52.256 55.962 Sample 96 Ford Escort 87 Olds Cutlass 96 Ford Contour Suzuki Esteem C-Line 1.5189 1.5162 1.5175 1.5162 ED-Line 1.5215 1.5189 1.5202 1.5188 F-Line 1.5284 1.5258 1.5274 1.5257 V 54.537 54.088 52.361 54.282 SamJfle 91 Ford Probe 88 Tgyota Celica 90 Acura Legend 91 Merc. Sable C-Line 1.5175 1.5174 1.5137 1.5163 E D-Line 1.5200 1.5202 1.5163 1.5189 F-Line 1.5267 1.5275 1.5233 1.5260 V 56.510 51.120 53.502 53.491 Sample Honda Accord 86 Chrys LeBaron 89 Pont Sunbird 95 Ford Contour C-Line 1.5162 1.5184 1.5174 1.5179 D-Line 1.5188 1.5211 1.5201 1.5205 F-Line 1.5256 1.5281 1.5271 1.5275 55.149 54.015 53.419 53.907 Sample 94 GM 85 Chev Celebrity Skylark 95 Buick C-Line 1.5161 1.5164 1.5156 1.5171 D-Line 1.5186 1.5190 1.5183 1.5197 F-Line 1.5254 1.5258 1.5257 1.5265 V 55.931 55.425 51.266 55.506 Sample 86 Colt Vista 87 Ford Ford Escort LX 92 Olds Cut. Sp. RIC-Line 1.5146 1.5164 1.5171 1.5175 R1 D-Line 1.5171 1.5190 1.5197 1.5201 R1 F-Line 1.5238 1.5257 1.5266 1.5270 V 56.123 55.793 54.879 55.183 Appendix Table 5.1: Refractive Index Comparisons. 54 Sample 85 Lincoln TC Pontiac Sunbird 93 Hyundai Sonata 92 Merc Tracer C-Line 1.5171 1.566 1.5166 1.5171 D-Line 1.5960 1.5193 1.5193 1.598 F-Llne 1.5265 1.5263 1.5265 1.5269 V Sample Oldsmobile 84 Ford Tempo 91 Oldsmobile 90 Toyota Camry C-Line 1.5170 1.5166 1.5196 1.5161 D-Line 1.5196 1.5193 1.5223 1.5187 F-Line 1.5266 1.5263 1.5295 1.5256 53.719 53.974 52.366 54.887 Sample 85 Honda Acc'd 95 Toyota Tercel 85 Chev Eurosport 89 Cavalier Z-24 C-Line 1.5160 1.5161 1.5169 1.5173 ED-Line 1.5187 1.5187 1.5195 1.5199 F-Line 1.5256 1.5256 1.5265 1.5268 V 54.317 54.451 54.195 54.773 Sample 93 Chev Cavalier 9O Beretta 85 Olds Brougham 88 K-Car Wagon C-Line 1.5166 1.5170 1.5165 1.5161 D-Line 1.5192 1.5196 1.5191 1.5186 F-Line 1.5263 1.5265 1.5259 1.5254 53.362 54.791 55.061 55.610 Sample 93 Olds/GM 89 Sunbird/red C-Line 1.5162 1.5173 R1 D-Line 1.5189 1.5199 R1 F-Line 1.5259 1.5270 V 53.498 53.268 Appendix Table 5.1 continued: Refractive Index Comparisons. 55 Appendix VI 186 Elemental Comparisons of Samples not Distinguished by Refractive Index 56 039:88 039:88 039:2: 030388 039:28 030288 < 2.: m: 039:2: 039:28 039:28 039:2: 039:28 039:88 < 22 m 039:2: 030388 039:2: 039:2: 039:28 039:88 meg: < 0332: 039:2: 039:28 039:88 039:88 033:2: m02:< 08:2: 038060: .3 3:932:65 87: moan—mm :0 2098an0 ”:6 0:20.:- 36:02? N956 $8.0 2.8.6 086 $5: 3R2 $2...“ 3.3 32.: :26: 33.6 30: $2.». 228 8%.: can ~22 $33.- 23: awed :mmmd: 83.x 32:: 393 E 0: 20% $2.: 2%.: 022 336 ovmod 3.3.6 Sod «20.2: 020.2. $3.2. $0.3 32.: 33: 836 $2 286 Seed 2.8.0 www.~ 9.8:» $22 Sam-.6 39m 023.2 88.0 3:4 802 E 0: figm :59: m2? . 2:2 255$. Far.— V6 33.0 285 :82 $2. «25 ~82 2:0 222 22.0 25 £22 £92 236 :2 226 282 53 232 $2 02222 9:2 922 832 82 302 22.4 832 232 22m :22 2 2 2.5 33 23% > 422 02-2-2 52 22-2-2 922 22-0-2 350 22.5 2 295.0 823 $85 :22 23 «2% 22.2 22.9 222 22.2 28 822 222 282 $2 «25 $22 222 222 $3 0232 282 $32 226 22 302 2%.” 32.4 $3 23 322 2 2 02$ 33 xwfi. > 8.32 22-2-2 222 22-2-2 ES 22-0-2 0.955 57 039:2: 039:2: 039:2: 039:2: 039:2: 030228 <22 2 030228 039:28 039:2: 032:2: 030228 0302—008 <02: m 039:2: 039:2: 039:2: 039:28 039:2: 039:2: m02:< 039:2: 039:2: 032:2: 039:2: 030228 0303008 moan: < .0805 03008.:3— >2 00202223005 82 00:22am .20 209-82800 6022:0200 _.e 030,—. 0:282? moved ammod uged wmod @0325 ngo $03.2 N02? 3:”: 2.2.: NNSG omNA m: mm.m wmvwd 2366 waofi 021v NORA.” MNm-Nd 39m $2.3 ovfid mam-e mmmA— 3: 0— 22$ 03%: ca: m.— 3;: 1% cmood name-o mbgd owed wan 2.5m ammwfi: 3.0.2.6 wmvfim 3mm: 85.: :86 com.— NmO: .m SVmN 3.36 omwd who: .v Ema-N Sam-c Nmmd wan-c: Name-h 22m. 6 m 2 :d 3: 0— wwoém wmmm: ow _ m: NE W: 000.020 020 ha 008.0 280 208.0 03.0 2220 22.2 22.: 05.0 0%.: 220 22.2 822 22.0 $2 2220 ~33 22.3 522 022 0:22 ~83 £02 22% ~22 302 08:: N2: 022 0:2 222 2 2 2.5 302 23.2 > 082 22-2-2 222 22-2-2 222 22-0-2 2.230 220 2 22:30 $3.0 $8.0 28.0 2.20 2220 29.2 23.: 2:2 902 020 $22 222 003.0 22 22.20 202 $22 2230 032 022,2 822 200.2 250 :3 302 22: 23.0 022.0 90.0 222 2 2 0<> 302 02.2 > 822 22-2-2 092 22-2-2 322 22-0-2 2.02. 0.3,.— S 0.22% 58 aims—8: aims—88 833—88 2528: 25288 25388 < 33 m 2,838: 2,828: aims—8: 3828: 2528: 839:8: < 85 m 2:385 833—88 833—88 3838: 38288 25388 m85< 2,828: 3828: 833—8: 3828: 38205 3828: m 25 < 88—85 guns-aux an conmfiwccma 82 338% MO :85qu0 62.5280 fie 2an £989? omwcd $86 836 mmod m8— .3 p.256 $34 c3}; Son; 324 $36 5: «coma ofififi m6: 6 SEN 33d awed Sam-6 aw; 88.x $3; VNNN< mflfi o— 83.3 hmmmg $3; $3; USE—«.5 85.8.— mm 33d 88.: 2.86 305 S 3.5 amt-6- 3R .2 omnov S2“; con: 3.36 :VNA Emma mOmfim 836 awed vommé waned Sums >36 $8M _ mmiuw at 6 33: 0. Gmdm can; 334 , NE m.— '3 $86 28¢ $23 $55 «2% 82.3 $3.: 326 Main 25 an? 85 :86 $2 «25 «82 5.3 586 as.“ msfiz ~83. E2 286 an?” 3»: 88.2 as: 832 23 23A 2 8.5 33 $3.“ > £2 052-2 3:2 eed-E ~22 25-0-2 22.5 2.5 8 285m 033 $85 $86 Sod «25 82.8 8%.: 32.» 812 $6 an? 85 286 $2 «25 ~83 ~32 £85 23 382 ~83. and 283 «mum 2E2 832 RS 32 2; 2% 2 SS 33 83% > £3 052-2 9:2 25-9-2 ~22 256-2 man—EU 35 5 8.95% 59 38202 38288 38288 38202 38288 38288 < 35 m 38202 38202 38202 38202 38202 38202 < 82 m 38202 38288 38208 38202 38288 38288 m 95 < 38202 38202 38202 38202 38202 38202 m82< 88202 333.28% 23 208828285 82 8.292% .20 2883200 6832200 80 2an 2282?- wvwod mmmod v.39: avod $3.3. $3.3 QRN6~ emf? gem; @822 3.36 m3.— mmmmd chhfi 2.36 ~mw.~ ommné amt-N- RNm-d v3.6 38.? moms waad 352 2 35mm hmmmg cam.— $3.2 9.0% ha wvcod 386 3666 Quad mwoméh ammo-3 QKNGN omvdv gem-2 cog; 3.86 32.— mmdQN mmowd 2‘56 _mw.m cap-v amnfim Emmd and 38.2 38.5 Goad SKA: 2 mafimm man; can; 33.2 a 885 285 ~28 ~23 «28 82.2 E; ~82 9%.: 280 as? 882 88.8 :3 2,80 888 $22 826 82 8:82 88~ 88¢ 83 88 282 288.8 83; V-~2 82 352 5 2 35 >52 88.8 > 882 25-8-8 882 85-9-8 .22 25-0-8 USE—EU 022::— ww «En—um 82:0 828 88.5 228 «228 82.8 88.: $8.» 828 v80 :82 ~22 :86 $2 «780 ~83 ~32 ~88 o~w~ 8:22 ~83 £82 £86 -~.~ 282 ~82: ~83 253 2; 282 5 2 03 BS 82% > 8.82 25-2-8 882 25-2-8 ~23 25-0-8 222.0 2.5 8 28.8 6O 38288 38202 38288 38288 38288 38288 < 22 m 38288 38202 38202 38202 38202 38202 < 22 m 38202 38288 38288 38202 38288 38288 m 82 < 38202 38202 38202 38288 38202 38202 m 22 < 08—02 3:08-82 3 2002828285 002 moi—Ham .20 202-82200 60:20:00 26 033. 2882? omwod 28.0 836 $90 32.3 man N384 0323 85m.— cmwmA 35.0.0 22: gown Sofia 262.0 and mmgN omwod Smmd a~w2 Sow-w @321 $25 mfld 2 08%? 533 $3.2 $3.2 USE—«.5 0220A mm 300.0 33.0 “.306 $0.0 $8.3 38.: «ENE 03.? moon; com: avgd a: mmmmN Sofia $.36 SQN 32.6 ade Rde v3.6 300.2 mmows 83.0 3:: 2 35mm Sun; 022 $3.2 620m 5 83.0 885 88.5 58.0 258 88.8 885 820.2 ~32. 080 52 E: :80 82 2,80 282 828 2.8.8 83 8232 8:8 ~oa~ 880 $3 382 $2.3 2.8.8 880 80: 22.2 2 03 302 ~28 > 88.2 25-8-8 222 25-0-8 382 25-0-8 32:25 0 can 3 22,—2.6 83.0 88.0 828 ”8.0 225 88.8 88.8 820.2 ~25. 080 8:... E: :80 082 «25 ~83 88~ 2.85 83“ mzaz 8:}. ~22 28.0 $3 282 $2.: 88.” 880 85: 32 2 0<> 302 ~38 > 882 25-2-8 88.2 25-0-8 882 25-0-8 22.28 «“25 a 2258 61 032:2: 25205 25288 03335 36288 95286 < 35 m 2522: 023.05 25288 2,628.8 3622: 023—2: <85 m o>_m=_o=_ 2,622: 9522: 2,622: aims—axe 36288 m 95 < 03335 03335 aims—axe 25388 2522: 023—05 m 95 < 48?: gauged 3 conmmsmcuma 82 335mm mo :OmEnEoU ”3:538 fie £an xmwcoqaxx mmmod $86 939% 366 mwoado mKONN QNNVN oavév GEM.— cmmo.— V986 2N; ammmd wNPN macs wvoa 393. $36. N926 ovad N302 $51: «336 392 E 2 5.3% can; $34 034 F33< 2:3: mm 3.36 386 369% wmod $8.3 @354» “SEX: cwfiww 2‘va 33; @366 awn.— nmvwd whavd $.36 NSN mowv.v Read thmd wmbd m3fim~ mmmbfi Qbmmd Gad E 2 35mm comm; can; 234 232—320 885 $86 $86 3.3 «2% :32. 823 SEN 83m V36 3:; $2.2 :86 $2 «25 85m ER 885 RS wznz 89m 23a 3mg 3:. 3m: 63.: 88¢ $3 3.3 3% E 2 SS 33 an: > 8%; 052-2 3:2 25-92 83; 25-0-2 3|; :36 $85 286 was «2% 38.3: 53%- V822 so: E6 32 ~83 :86 Q: 25 89% $23 $86 $3 msfiz 2m: 88a 326 S3 3»: :32 8%; $3 at: 3% E 2 BS 33 5% > 8%; 052-2 52 25-92 EB 25-0-2 5 team Es— «.maam 62 2,2282 2,2288 25202 25288 2,2288 22288 < 25 2 25202 2,2288 22.2202 22.2288 2,2288 25288 < 32 m .825 250382 3 2.22.2225 82 .8383 we 2859280 682228 fie 853- 298%? 2,2202 25288 222202 26288 2,2288 2,7288 m 32 < 2,2202 2,2288 25.202 2,2288 22.2288 22.2288 2 25 < 336 memod NNeee Que-O N2 me.o_ meag- vave 3nd mm— m._ mhwfig eemed Gem; cmoad wmvmd Seed EKN Saw; ogmg vmvee Km; 2 ~85.” Rhea gem-ed emu-m E 2 3.26m emmm._ $3.— ~e~ m2 1% wag-c memod N89 .e 390 Seed— memafi quvd vomd m2 m2 mum—A eegd ommé cmoad anm.m Seed and 33: 94%.— vaee Km.— _ fimafi :3.»- Qeeee Ens-m 2 0— :vém emmm._ hm _ m2 _e~ m.— .35. .2. a. ma 23° 2.85. 886 3.3 A2% 28.8 28.2 222 83% 25 822 22: £36 22 «25 222-. ”22 :22 22m 2222 «83. 2.23“ 822 $3 222 22.2 53: 233 822 222 2 8; 33 :22 > 082 25-2-2 2:2 25-5-2 22 25-0 - 2 e38< «ESE mm 295% R35 $86 222 Sod 22m :22? 82.2 222 822 28 23.5 2:? :82 22.. «25 882 ES 886 23 322 cam-Z 8:2 2mg 23 322 88.: £26 226 3.3 222 2 35 BS 52% > 032 25-2-2 2:3 25-5-2 $52 25-0-2 :80 3.. £- 8 can—am 63 039:2: 03335 36205 95286 $6288 2,6288 <35 m 032:2: 039:2: 023—05 022:2: 03335 033.05 < 35 m 48?: $3933“ 3 uoaflnwauma 82 838mm mo acmEQEoU 6035280 fie Baa-- £32??- 2532: aims—83 2522: 033—88 36288 36288 m 35 < 3622: 032:2: 033—2: 3632: 03.0.22: 033.05 m 25 < waved mom-ed ~39: mi; N_ 3.2 $3.5 RES vomd 3:”; mum: 336 Own; omoad mewN 336 vwfim $92 $va wmgd Km; :36 hug-M $36 35m 5 2 33% can; bwfi m4 #2 m; .338 So PH ma 336 3.86 3.36 $56 2 mmfiw 8:6- 3R .2 32:. ~:m._ ooh: 3.36 gm.— Pmmd 8de 836 awed vommé wooed gums a: $8.2 33% at 6 33: E 2 Swan cmmmg wwfig m2 m4 Ila-«Ilsa .5 a; a. £23 885 ~32 mac «2% 23.; 8:6- 255 amne- M5 «:2 8:; £86 32 «25 Km? M82 386 an: mzhz «82- 803 £56 5% 3m: $8.2 $3.» 3:3 $2: 3.2 2 u<> 33 8mm > on”? aid-E $22 053.3 ~22 25-0-2 .5...“ :0 an can—am 83¢ #85 a8: 33. seam 88.8 28.2 amt-N 83...- M5 SR4 82: R85 22 «25 am? $2 :36 $3 wsfiz 3a? 35% 826 $3 3w: «3.2 52: 232 mood 352 2 BS 33 23% > 8%; 052-2 2:2 aid-E 22 25-0-2 282 2:8: ma gag—am 64 020205 02020000 0202000 020205 02020000 02020000 .0 02 0 020205 020205 020205 020205 020205 020205 .0 as 0 02020000 020205 02020000 020205 02020000 02020000 m005 < 020205 020205 020205 020205 020205 020205 m35 < .0005 020000-030 03 0020225005 002 02058 .20 000203500 609558 2.0 030.0. 50:005-4- owvcd name-o N896 086 2 mwfiw 8:6- 300 .2 amndv N20”; 82.2 000.36 20.0...— Kmmd mowhN 2036 $96 veg-v wgqm €0N6 haw-m vwmcdfi mag-w $000 6 awe-o2 2 2 Smdw can; ww _ m2 Ne _ m2 Ila ego-o name-o mmocd 086 3 3.5 amt-6- 300 .2 mmmdv N20“; cog-2 0.0.86 3N.— hhmmd womb-N gas-Q awe-m comma“. wooed bbnms haw-m $8.3 gin-w 0300 6 awed— 2 2 Smdm cam.— ww _ m2 N3 m.— . Julia 00 00_ 0 500 0.0 0,—- 00 0000.0 0000.0 0000.0 000.0 02000 0000.0_ 0000.0 0000.0 03.: 0000 0000.0 0000.0 0000.0 0:1 0200 0000.0 0000.0 0000.0 000.0 02002 0000.0 0000.0 0000.0 000.0 2002 0000.0 0000.. 0000.0 02.0 2002 2 SS 300 0000.00 > 0000.0 80.0.: 0000.0 000-0-E 0000.0 80.0.2 052000 0250.— : 0. 50m 0000.0 0000.0 0000.0 30.0 02000 200.00 0000.00 0000.0 000.00 00000 200.0 0000.0 0000.0 000.0 02000 0000.0 0000.0 0000.0 000.0 02002 0000.0 200 0000.0 000.0 2002 0000.: 0000.0 0000.0 000.0 2002 2 35 30.0 000.00 > 0000.0 80.0.2 0000; 25.0.2 0002 02-0-2 0.925 65 020205 0202000 020205 020205 02020000 02020000 <85 m 020205 02020000 020205 020205 0202000 02020000 <35m .0005: 020000.030 03 0002052505 002 003.5% .00 00002-80500 600558 0.0 0500- 55000900 020205 020205 020205 02020000 02020000 02020000 0 22 < 020205 020205 020205 020205 02020000 02020000 0 22 .0. 0000.0 0000.0 0000.0 000.0 0000.0 0000.0 0000.00 000.00 0000.0 0003 0000.0 000.0 0000.0 0000.0 0000.0 000.0 0000.0 0000.0 0000.0 000.0 0000.00 0000.0 0000.0 000.0 E 2 000.00 0000.0 0000._ 0:02 23020.05 0000.0 0000.0 0000.0 000.0 0000.000 0000.0 0000.00 000.00 0000._ 000: 0000.0 000.0 0000.0 0000.0 0000.0 000.0 0000.0 0000.0 0000.0 000.0 0000.0_ 0000.0 0000.0 000.00 E 2 000.00 0000._ 0000.0 0000.0 [lg-0.0% 00 0 20.0 0.00 0000.0 0000.0 0000.0 000.0 070000 00:00 0000.0. 0000.0 000.00 0000 0000.0 000: 0000.0 000.0 02000 0000.0 0000.0 0000.0 000.0 02002 0000.0 0000.0 0000.0 000.0 2002 0000.0 0000.0 0000.0 000.0 2002 2 00$ 23 000.00 > 0000._ 22.0.2 0000._ 0200-00 0000._ 22-0-00 “Macaw finch V6 Sufi—am 0000.0 0000.0 0000.0 000.0 02000 _0_0.00 0000.0_ 0000.0 :000 00000 000.0 0002 0000.0 000.0 02000 0000.0 0000.0 0000.0 000.0 02002 0000.0 0000.0 0000.0 000.0 2002 0000.0 0000.0 0000.0 000.0 2002 2 SS 200 000.00 > 0000.0 22.0.0.0 0000._ 22.0.2 0032 22-0-2 0.0800 66 020205 020205 020205 020205 020205 020205 < 22 0 020205 020205 020205 020205 020205 020205 < 25 m 02020000 02020000 020205 020205 02020000 02020000 m25< 020205 02020000 020205 020205 020205 020205 m 25 < .2062 02008-002 03 6020525005 002 02ng .00 0002-80500 60:50:00 26 0509. 5200054. 500.06 ommod 60666 686 35.3 wag-v— 0.3.6.0 :vdm 332 222 6:66 0.0m; $50.0” avgm 6626 0.8.0. 0.300“ goo.— 0026 Sod 33.x 86:0 3.066 626 2 2 mvam mom-2 mam-2 83.2 lama-nag ammcd 386 0.0666 3066 Emu-c comm-v N636 3nd $0602 5066.2 6366 m2; maomN onmvd 0.6066 wand :09..— 6822 6366 com; 32.6 23.0“ 60606 on: E 2 $6.6m awn-2 60.3.2 903.2 E:— 63 500.:— an 0000.0 0000.0- 0000.0 000.0 02000 0000.00 0000.00 0000.0 000.00 0000 0000.0 0000.0 0000.0 000.0 02000 0000.0 0000.0 0000.0 50.0 02002 0000.0 0000.0 0000.0 000.0 0.000: 0000.0_ 0000.0 0000.0 0_0.0 2002 2 2 00$ 23 000.00 > 0000._ 0200.00 000.0 22.0.2 0000._ 22.0.2 6.5255 050.5; 0355 0000.0 0000.0 0000.0 000.0 02000 0000.0 0000.0 0000.0 000.0 0000 0002 0000.0 0000.0 000.0 02000 0000.0 0000.0 0000.0 000.0 02002 0000.0 0002 0000.0 000.0 2002 0000.0 0000.0 0000.0 000.0 2002 E 2 00> 202 000.00 > 0000._ 22-0-00 0000.0 22-0-00 0000.0 025.2 32> :00 00 0.05% 67 02020000 020205 020205 020205 02020000 02020000 < 22 0 020205 02020000 020205 020205 020205 020205 .00 25 m 020205 020205 020205 020205 020205 020205 m005< 02020000 020205 020205 020205 020205 020205 m 25 < .0065 02000-602 03 6020525005 002 00358 .20 5002006500 60:50:00 26 0300- 56:09:00 3.66.6 m6 2 66- 0 0- 0 6 .6 mmod Smog-.0 3666— 0.60.6.0- 306.3 awe-2 832 00.066 hem-2 6mmm.m onwafi 6606.6 8— .m mmmmé :90.— 00006 20w.N hmhmfiu 33.000 663:0 656 E 2 366m mcmmé mam-2 6632 6.0355 022:5 N366 owned 6 N 66 .6 68.6 mamm- 2N~ m6mm.m .0660 60 36.8 wmmmg mam—.2 0266 m8; mam-.0” 663.6 0- 666 .6 «mo-m $3.0 chafim 60 0. N .6 mend 0.63.2 20va 0- 666 .6 one-o2 2 036m mommé m2 m2 @632 . can—0H 6.8..“ 06 0000.0 0000.0 0000.0 000.0 02000 0000.00 0000.00 0000.0 000.00 0000 0000.0 000: 0000.0 000.0 02000 0000.0 0000.0 0000.0 000.0 02002 0000.0 0000.0 0000.0 000.0 2002 0000.0_ 0000.0 0000.0 000.: 2002 2 2 00$ 23 000.00 > 0000.0 22-0-00 0000.0 000-0-E 0000.0 22-0-00 805% 606:: E ma 265% 0000.0 0000.0- 0000.0 000.0 02000 0000.00 0000.00 0000.0 000.00 2000 0000.0 0000.0 0000.0 000.0 02000 0000.0 0000.0 0000.0 000.0 02002 0000.0 0000.. 0000.0 000.0 302 0000.0_ 0000.0 0000.0 0_0.0 2002 2 2 00$ 23 000.00 > 0000.0 22-0-00 0000.0 22.0.2 00002 22-0-2 .5550 00500.2 0.0800 68 830202 830288 830202 830202 830202 830202 < 300 0 830202 830288 830282 830202 830288 830288 .4. 82 m 830202 830202 830202 830202 830202 830202 009030 830202 830288 830202 830202 830288 830288 00 35 < 90006.6 6mm6.6 6066.6 606.6 8.0.0.22 m6mm.m 0.660 .60 wM6.N6 620.0 32.— 0006.6 m3.— m0mm.m 66m0.~ 0. 666 .6 Nm6.m $5.0 60.60..~ 60 0. N .6 mom-m 0.600-.2 66006.6 0.666 .6 606.60 2 006.0% 832 mam-0 660 6.0 '3 0306.6 626.6 60 66 .6 68.6 33.6w 6666.3 0066.0 20.8 3.00m; 260.0 600.66 5&2 6630;” 656d 66m 0 .6 006.0. 0.6 SN 6666.0 0000. 0 .6 26d 663.6 666:0 0.0.06.6 6N0.6 2 www.mm m6mm2 0606.0 6606.0 AU ONE—0H. munch .0862 8388-800 03 uoammswcuma 82 08—68% .00 0803-86800 ”68:20:05 0.6 260,—- 00328690 0000.0 0000.0 0000.0 000.0 02000 0000.00 0000.00 0000.0 000.00 0008 0000.0 000: 0000.0 000.0 0206 0000.0 0000.0 0000.0 000.0 02002 0000.0 0000.0 0000.0 000.0 2002 0000.00 0000.0 0000.0 000.: 2002 2 80> Boa 000.00 > 0000.0 25.0.2 0000._ 2.0.9.2 0000._ 80.0.2 00. 328m 206: 00 m6 268% 0000.0 0000.0 0000.0 000.0 02000 0000.00 0000.00 0000.0 000.00 006 0000.0 0003 0000.0 000.0 0205 0000.0 0000.0 0000.0 000.0 02002 0000.0 0000.0 0000.0 000.0 2002 0000.00 0000.0 0000.0 000.: 2002 2 90$ 33 000.00 > 0000._ 25-0-00 00_0._ 000-00-E 0000.0 2.0.6.2 00 300% 3:. m 00 0.600—am 69 830202 830288 830202 830202 830288 830288 < 22 .0— 830202 830202 830288 830288 830288 830202 < 22 0 830202 830288 830202 830202 830202 830202 m 22¢. 830202 830288 830288 830202 830288 830202 m022< .0862 8380686 03 6820262005 82 026806 00 2003-26200 ”68:20.08 0.6 260.0. 262866.00 6006.6 60N6.6 N60 6 .6 N066 6N60 .60 0000.6 N 00. 0. .0 630.3 6060.0 6NON._ N636 000.2 066N.m 606m.N 6600 .6 060.N 0666.N 6666.6 0 660. .6 6Nw.0 0666.0 6060.— 02.0.0 0.2.0 2 6N66.mm 030.0 660 0.0 060 0.0 “$650.00 0225.0 66 0606.6 003.6 0066 .6 006.6 Nm6m.mm 366.0.— 60 6N .0. 60.0.3 060N2 602.0 6606.6 00: 6060.0. 66N6.N 6600 .6 069m 6Nm6.N 60.06.— 6060 .6 wm0.N 6900.6 0660.0 N060 .6 N006 2 0N0.Nm 66Nm._ 6660.0 0000.0 .8820. 3.82 N6 0:200 80 0.0. mm 0000.0 0000.0 0000.0 000.0 02000 0000.00 0000.00 0000.0 000.00 2000 0000.0 0000.0 0000.0 000._ 020.0.0 0000.0 0000.0 0000.0 000.0 02002 0000.0 0000.0 0000.0 000.0 2002 0000.0 0000.0 0000.0 000.0 2002 2 2 SS 33 000.00 > 0000._ 22-0-2 0000.0 22-2-2 020.0 22-0-2 2822 25040006 0000.0 0000.0 0000.0 _00.0 020.0 0000.000 0000.007 0000.00 000.00 2000 0000.. 0000.0 0000.0 000.0 02000 0000.0 0000.0 0000.0 000.0 02002 0000.0 0000.0 0000.0 000.0 2002 0000.: 0000.0 0000.0 000.0 2002 2 2 0<> 33 000.00 > 0000._ 22-0-2 0000.0 22-2-2 0000.0 22-0.2 70 030202 030288 830202 030202 030288 030288 < 82 m 030202 030288 030288 030288 030288 030288 < 22 2 830202 030288 830288 030288 030288 030288 008200 030202 030288 030288 030288 030288 830288 0— 82 < .0862 03008030 02 6822002005 002 022200 .02 28202220 ”68220220 0.6 220.0- 260822.00 0606.6 0606.6 0066.6 006.6 0006.60 0606.0 0600.6 060.6 0000.0 000: 6606.6 600.0 6066.0 0000.0 0666.6 000.0 0060.0 6000.0 0006.6 000.0 206.0 0000.0 6606.6 000.0 2 2 000.00 6000.— 0000.0 0600.0 .0980- 30 0.0. 06 6666.6 0606.6 6066.6 006.6 6060.0 0006.0 6600.6 660.6 0660.0 0606.0 0006.6 000.0 0060.0 6000.0 6066.6 606.0 0000.0 6600.0 0006.6 600.— 0000.0 0006.0 6066.6 000.0 2 2 600.00 6000.— 0000.0 0600.0 6.000000 20:00.0 2.080-,0 20000 0000.0 0000.0 0000.0 000.0 02000 0000.00 0000.02 0000.0 000.00 208 0000.0 0000.0 0000.0 000.0 0208 0000.0 0000.0 0000.0 000.0 02002 0000.0 0000.0 0000.0 000.0 2002 0000.0 0000.0 0000.0 000.0 2002 2 00> >52 000.00 > 0000.0 22-2-2 0000.0 22-2-2 0000.0 22-0-2 5030”..— fl—Em o—flaam 0000.0 0000.0 0000.0 000.0 02000 0000.00 0000.: 0000.0 000.00 206 0000.0 0000.0 0000.0 000.0 0.205 0000.0 0000.0 0000.0 000.0 02002 0000.0 0000.0 0000.0 000.0 2002 0000.0 0000.0 0000.0 000.0 20002 2 80> 322 000.00 > 0000.0 22-2-2 0000.0 222.2 0000.0 22.6-2 71 9632: 25283 aims—88 26205 36288 95288 < 32 m 0233.: 03335 029:2: 3622: 022:2: 033—05 <85 m 032:2: 3622: 023—88 2522: 033—38 033—88 m 35< 3622: 033—88 033—88 039:2: 36205 9522: m 35 < 48?: gauged 3 gamma—magma 82 8.99% we soar—3:80 602550 fie 2an xmvaoaadc. 336 $86 @332 $56 33.8 mKon QNEQ oat: comm; ammo; $36 2N; ammmd mafiw :36 wvod 33+ vmwvd 32d 034m ~33: $3.2 amend moQS 0— Cmém can; 334 Eng PSS< 2:3: mm 535 $23 $.36 Sad 23.? Smfiwm wBNN cowém 3cm.“ cam; Ides www.— Nonod «find 336 mmad oamnd chd and 306 $3.: 386 33.: 3M; 2 233% wan; 33; SEA flan—SQ GHGNGH. Ga 885 $86 £86 8.3 «2% mm-d~ 88.: ~23 08.2 $6 -_2 ¢~v~2 $36 :2 «25 88.... amwo~ ~83 ~3~ wsfiz 886 #22 ~83 -- 3w: :3: £86 £53 a; .52 2 BS 33 ~33 > 52 8:472 ~82 053-2 ~22 25-0-2 Euoumfl 335m can—am 823 $85 3.8.: oz; «25 mm-d~ 85.: ~23 oS- 25 ~22 v~v~2 323 R2 «25 8o? ~83 ~83 ~93 $32 won: «23 ~83 -~.~ 3w: 33g £86 836 a; 3.2 2 SS 33 ~w~$ > ~22 052-2 ~22 25-92 ~22 25-0-2 E83”.— Eausm «En—am 72 32222 022288. 022288 032222 032288 033.88 <35 m 2,222: 022:2: 032:2: 032:2: 022288 3222: < 85 m 3222: 032:2: 032288 3232: 032202 032286 mega < 32222 2,2305 2,2288 222:2: 3222: 032:2: m 22 < .222: 2,3030% an 3:22:55 32 moafiam no 22859280 60:52.8 fie 29d- 228%? 888 888 -8.~ ~88 28.2 ~23- 82.2 22:. ~:2 8:2 888 :2 R-~ 8-.~ 888 ~8.~ ~83 -8.~ 828 5% 88.2 -v- 828 222 2 2 8.8 ~82 ~22 , ~22 1% 888 88.0 ~88 288 82.2 $2.: 888 ~32 -~2 ~82 28.8 ~82 ~83. ~82 288 -~.~ ~83 8-~ 828 -~.~ ~82: ~23 ~88 2; E 2 ~88 ~82 ~22 ~22 82.5 85 2 888 $88 88.8 ~88 seam --- 8a.: 28.» 88.2 25 ~22 --2 888 P2 «25 8o~.~ --~ ~88 ~28 ~22 ~o8.~ 2:2 ~88 -~.~ 282 v8: -8.~ ~88 ~:.~ 222 2 35 BS -~+~ > 82 22-2-2 ~22 22-2-2 ~22 22-0-2 88.2— 23am? 88.8 288 88.8 ~88 28 82% ~23: 28.» 822 28 -22 --2 888 :2 ~25 8o~.~ m-- ~88 ~8~ ~22 ~c8.~ 8:2 ~88 -~.~ 222 882 -8.~ 88.8 2; 222 2 35 33 -~.- > -~2 22-2-2 ~22 22-2-2 ~22 22-0-2 finlg 2.52m 73 022222 022288 022288 022222 022288 022288 < 22 2 022222 022288 022282 022288 022208 022288 < 32 m 02.0.2022 022288 022288 022282 022282 022202 m 82 < 022288 022222 022202 022288 022288 022288 2 22 < .8222 0288.202 22 2022:2225 82 ~2ng .20 28229200 ”2022280 2.0 035. 22020222.. omwod 286 88.2 «35 33.2 nut-d ~22-.2 92.3 @322 £52 N236 ~32 voomé gem-N 3:6 25d maomd omwod 33.6 mg.— Soww 233.2 ~22-2 ~26 22 02 omoadm 2.322 22m.— $22 22:23.5 822:5 an £36 886 N326 286 Emmi-m Ont-6- meta-2 ammdv 2202 82.2 3.3.2 322 Emma Swfim 386 232 39.2 wooed gums 32m 228.2 332 3R6 $23 22 2 Gmdm 232 mm;— SE2 '3 --.~ --.~ ~83 ~8.~ 22 ~82 --.~ --.~ -~.~ 25 ~82 88.2 ~83 82 «25 ~82 --~ 283 ~_~.~ ~22 -~2 82.2 --.~ -2 :82 ~82 2-.~ --.~ -~.~ 322 2 8; 23 82.8 > ~82 ~22-2 ~22 22-2-2 ~22 22-0-2 2300< .223! 02923 --.~ --.~ ~83 ~8.~ 22.2 ~82 --.~ --.~ -~.~ 25 ~82 88.2 ~83 82 25 ~83 --~ 283 ~_~.~ ~22 -~2 82.2 --.~ 82 :82 ~22 2-.~ --.~ -~.~ 222 2 35 33 ~38 > ~82 222-2 ~22 22-2-2 ~22 22-0-2 .2822 .228: ~22—Sam 74 95202 38288 38202 25288 95288 838288 <95m 3628: 36288 36282 2,8288 36288 95288 < 25 m 839202 2,6288 38288 95288 8,5288 2,6288 m 85 < 8528: 85288 $7.28: 38288 36288 38288 m 95 < .889: 8288.23“ 3 322%:sz 82 838% MO :85an0 682558 fie 832—. 58:33.. awed 386 3.86 v36 28.? 833 SEN 8mg 33..— oflmg $.36 32 855 Vde 886 mmo.m 83m Sam fimwd man 83.: owned mum-us 33w 2 53% 832 2:2 SR; r3 mmmod $.85 aged 39° 33.3 28.2 amt-N 313- 8mm; 3.32 ‘98.: £3 manna matum :36 wvod 3mm;- vawvd New; ogd mmmnfi $3.2 336 25.2 2 23% $32 $3.— Em.— fihcou< «nu—3m ma 885 $85 $86 «mod «2% 882 £23 £86 83 E5 88.. at: 286 a: «25 ”32 3.88 236 23 msfiz Rm? 8%: 888 on? 3»: 3m?“ 28a £86 Ea Eaz 2 8.5 33 22.3 > 822 82-8-2 ”22 053-2 ~22 25-0-2 6.500(- aux—cm u—N—flam 885 83° 286 «85 25 882 886 8.8.: 88 25 ~82 3:: :86 £2 «25 ”82 $23 286 23 3.6.2 Rm? can: 886 $2 3»: was 23m £88 £2 2R2 2 8.5 33 $3“ > ENE 25-2-2 $23 053.2 ~22 25-0-2 Fauu< «£66m can—am 75 .082: 328.282 >2 62822285 82 88—92% .20 28.82an0 68:22:00 26 2an 8.205292 838202 38202 2,8288 2,8288 28202 28202 o>8288 28202 28288 28288 o>8288 28288 < 22 m m 22 < 28202 38288 28288 2,8288 2,8202 o>8288 28202 28202 38288 ”$8202 2,8288 28288 < 82 m m 85 < 6366 $86 N666 .6 636 man 2 Rm 293.: 63.“- 6 mmvfim 5mm; 82.— :m66 vow.— Nme .m hgmd 3.666 omwd NBS-v gmmd m: 6N .6 Nm~.m wax-.2 Nam: 63». 6 m _ 6m 2 2 39% man.— af m2 mg m2 mun—«=0 820 ha 336 memo-c N N 66 6 $66 N _ 3.2 monas- Navv6 3nd m2 m2 mum _ ._ 6686 6mm.— Omoad wmwmd N686 find 39: Suva; X4266 Km.— 2 ~86 Kcmd 936 6 emu-m E 0— Evin can; 5 2 m2 52 m2 $23 $82 282 ~82 «222 283 28.“ 22.2 8% 220 ~82 an: :22 22 2.20 mg: 2.~v.~ 28.2 22~ 8:22 ~82 2%: 222 82 282 2.82 282 22.2.2 22” 222 2 045 302 22.2 > 222 22-2-2 2:2 22-2-2 ~22 22-0-2 283‘ 2:3: via—am $23 88.0 382 ~23 «228 232 223 222 83 220 ~82 2E: :22 2: «220 282 $~2~ 282 S2~ 8222 an? 222 ~32 22 282 222 222 222 23 352 2 0<> 302 22.8 A > 282 22-2-2 2:? 22-2-2 ~22 22-0-2 2.884 «ES: 225m 76 822222 822222 822288 822222 822288 32288 <82 m 922202 32202 82388 32222 822288 32288 <82 m 32222 95288 022288 822202 8,2288 2,2202 m32 < 2,2222 32222 822288 85202 822222 82228 m 32 < .2825 8288qu 3 3222-2225 22 Z 22223 .22 282-82220 6822228 26 2229. 2282.5 $32 $82 282 323 83.8 23.: 22%. 22.2 82.2 82.2 2.32 22 22.2. 82.2 882 23 322 22.2 222 :2 22.2 23% 22.2 22.2 2 2 22.2 82.2 2:2 G23 '3 823 $82 $82 236 22.3 22.: 32.2 22.2 22.2 822 :22 33 ~83 $22 2222 22.2 ~83. 22.2 22.2 ~22 22.2 22% 233 2; 2 2 232 22.2 222 ~22 , Inn-lasso also 2 82:. 282 222.2 22:. 225 E22 228. 2.8.2 3.2 25 52 82.2 :82 SE 226 882 22.2 232 22.2 £22 £22 322 :82 28.2 222 22.2- 228 :22 Si 222 2 2 8.5 322 22.2 > 82 22-2 - 2 2:2 22-2-2 822 22-2-2 I3 222.5 8222 $82 2832 «.32 «222 E22 22.2. 28.2 3.2 25 52 82.2 :82 SI «25 882 38.2 28.2 23 2222 322 22.2 :82 28.2 222 2.23 82.2 :22 a: 352 2 2 8.5 322 222 > 82 22-2-2 2:2 22-2-2 823 22-2-2 o—Dam HEP—02 #6 222% 77 8,2202 8,2288 95288 95288 2,2288 85288 < 25 m 2,2202 2,2202 32208 32288 32288 25288 < 25 m 2,2282 2,2202 2,2288 8,2288 2,2288 2,2288 m 82 < 32202 2,2202 85288 32288 85288 85288 m 82 < .8825 gauged 3 3222255 82 832% Mo :85an0 62.228 _.w 2an 228%? wowed memod ages mmod 3%.th 39963- chm-m .3 mm. 5 2.32 mm:._ QNNQG aw_._ mmwvd ngd N366 3N6 med 232 mm: 6 acmd mmmvd >3: .0 :vad 35.5 E 0— SQNm ENQ— Noam; mug; 53.50 than ca 836 38.0 macs wmod 882K Vmfimd aqé .N N gvdv R3”.— Pfig :36 cm; Cmmd wmvwd $256 wmod owgé NCSN :36 32m $2.3 acmmfi nmmad mmm.: E 2 Ngém amNmA 03 m2 v2 m2 32:25 «MER— a 822 :85 2.8.5 835 25.5 8%.” 386 83.5 8% 25 :51 28.2 235 9.2 25 825 382 £85 :22 2222 as: $82 28.5 82 222 22:. «.83 £25 83 222 5 2 8; 33 83 > £2 25-2-2 ~82 25-2-2 :22 25-0-2 «0:00 3: ch. aw u—Naam 823 285 Re: 2.3 «225 R32 EMS. 38.2 222 26 52 822 :86 83 2,56 85.... 382 285 22 £22 «22 Emma :85 23 322 2.83 225 53 a: 222 5 2 SS 33 52% > 82 25-2 - 2 2:2 25-2-2 83.2 25-0-2 22.5 3.82 3 via—am 78 8,2202 2,2282 32288 832202 32202 32288 <92 m 2,2202 8,2288 2,2288 25202 32288 32288 <92 m 32202 25202 03.2288 32288 95202 85288 m 82 < 022202 32288 32202 2,2202 32288 32288 m32< .8805 8282.82 .3 32222235 «oz 838$ .20 282.2an0 ”3:228 H6 2an 228992 885 285 225 ES 22.2 :22 82.: www.2- 222 :22 882 22 ~83. 2R~ 32:0 :3 ~22. $-~ 222 22 823 23: 222 22: 2 2 22.2 E~2 S~2 E2 m 222.0 220 a 22:0 823 2.82 2.20 83.0 ~22. ~22 SE 2.22 82: 2.32 m-._ 203 :S.~ 322 ~$~ ES 2:2 ~83 22 ~23. 22: ~22 22 2 2 22m :~2 $2 222 23.. S~ 2:25 2 ~23 885 38.5 ”85 25cm 32.: 38.n- §~§ 82mm 220 :22 ~82 282 22 2220 ”ES -2~ 3.22 at: 2222 823 52 ~82 $2. 322 R22 82.: ~22 22.2 222 5 2 8.5 302 83.2 > :~2 25-2-2 S~2 25-2-2 E2 25-0-2 .2355 0225.— am 2.52m 223 285 :22 $3. 25% 3.5% 28.8 ~23. 88.: 220 232 2-2 232 ~52 dw22.0 §~.~ 223 882 2.2 2222 28.~ «~22 2:2 ~m~.~ 322 22.: 2.22 22.3 83 222 5 2 0<> Bo.— ~om.mm > -~2 25-2-2 ~22 25-2-2 222 22-0-2 15ou a..._=lo.<_ 3. 2 Sam 79 3.2202 37.202 2,2288 32202 95202 32202 < 32 m 022202 32202 32288 2,2202 2,2202 32288 < 25 2 32202 32202 32288 2,2202 32202 32202 m 82 < 032202 32202 32288 26202 32202 222202 m82 < .562 gnombom 3 3222225 82 332$ 20 28222200 62228 #6 2an 22893 mmmod meod .6866 v.36 mwooéo mfiodm 6mm?“ 823» comm; cmmog Ema-6.6 m—NA aNNmfi wNRN 2666 $66 360*. vmwvd N626 ovmd N202 352.3 666.66 mac-N— 0— 23% can; 3;; 3m; Ego< 223mm mw nmmod 5356 $666 $56 28.9. Nomm.wm 236 wowdm 33”; 332 R666 mum.— Nonod aunt-N 66666 Sum-N samba Sim-N 6566 meM 33.: owned mum-m6 3&2 2 534% can; 53m.— 22m; lg acvcd N986 «<66 6 N36 «265 gov-co NVE .2 663- .n Sag-m M20 38; _ $66 336 m8; 2220 33 .m mehfi 6666 6 mea.m 3.422 6 ~ 33‘ NON-6N MMVN 6 oofim ZR: 5 _ 8.2 83.x Nm6u 6 63.3 222 2 U<> >901— ofl 36w > van.— o2_-m - a win; o2_-Q - a 33.— 2.2-0-2 EU 3 flan-am 6636 $86 266 6 ~36 mZEm goo-cc Nag .2 663. N 565m M20 Smog _ Sad m6 3 6 m8; «ZED 32 .m vwmbN 6666 6 Mead 3222 m 2 31a Nomad MWVN 6 confi- Jim—2 23.2 332 N63 6 03.3 222 o_ U<> >90:— 3 madm > mem; 027m - a can; o2_-Q - a $32 0270- a 20 Va 295% 80 03335 03385 36388 03335 039.88 039588 < 85 m 36288 023320 95288 33288 039588 03335 < 95 m .59: 038.30% 3 352%.“:me 82 $3.5m no 833800 60:55.8 fie 2an £259? 25283 033.2: 03335 02335 36288 033—88 m 35 < 2522: 2522: 2,6336 2,6288 023—38 023—05 mSE < Jana-sch 53. {2.3. Inn 1 336 mama-c aged wmod wamwdw— Sam-9“- 35». .mm. 8a.:- hvwmé 80¢.— E 3 6 Nb g A Go: wag-N NNNQG mwfifi nmmfiv 38% 3.26 an.m Kemd ~ cmwvd 3‘66 at: E 2 agém comm; >3 m; :3.— [a good 38.0- 3.36 Vmod wade goo-Nb.- msm- .2» 03.3 Nmmmg one; 3.36 mag wag .m eth eQaa 6 NNQN mug-v v2 _.m 3K Nd awed 33.2 van-w «mm-NR 6 50.2 E 0— 303 mean.— 8%.— :3.— 285 2.85 583» «.35 «225 8:3 5%:- 332 2.3.2 25 22: 835 $85 33 «25 39.5 «~82 :85 32 3,32 3.35 55.: ~55 83 3m: 23% 2;.“ 3.2% R3 32 5 SS 33 88.2 > 252 25-2-2 52 25-5-22 ES 25-0-2 22.5 ma 253.5 235 $85 35.5 «35 «225 3:3 5%: saw 58.: 226 :2: $2.3 $3.5 33 «25 $35 ~23 £85 83 3552 $85 52.: ~55 8.2 3»: 232 2:: 52% E: 222 2 BS 33 88.2 > 252 25-2-2 52 25-5-3 ES 25-0-2 555 a 2.5.5 81 32305 2,2305 2,2388 2,2305 9,2205 92205 < 25 m 2,2205 2,2288 2,2286 32288 32283 32288 < 85 m 32205 2,2305 2,2388 32288 32205 033.02 m35< 032:2: 32205 32288 32288 32288 020288 m 35 < .089: 352.20% 3 Baflawauma 82 moEEmm 60 5820an0 6025500 66 033. 26:25.2 weeod 386 3666 636 mmomdh 33.: QRN6~ omvdw mama; oomfi— 3236 m2; mmaad «mafim 2‘66 EQN ommwé omhhd 23.6 unfim wmocd— anew-- 3666 35.3 E 0— man-mm hmmné cam.— 33." 6.8,.— ha 336 38.0 3666 wmod $3.3 win-V 666‘: £65. mug; 336 6.366 aNmA hmvwd flaw-N 6366 NS.N mcwvé _mca.N awn-N6 wmhd 366N— mmnhfi 63.56 Gad E 0— 35mm comm.— @634 2.34 239520 «~85 385- 23.5 3:. «225 $2.28 83.3- 22.:- 222. 230 ~83 885 33.5 23 «220 53“ 892 88.5 23 3222 52m.“ 322 252 83 222 2.2.2 ".22 23: E5: 222 5 2 0<> 33 532% > 222 05-2-2 822 25-0-2 3:2 25-0-2 3 2225 28.5 $85 28.5 my; «225 8:3 5%: 322 .032 220 22: 83.5 285 33 «220 032m 2:: 530 83 £32 $82 0%: 22¢ 82 3»: 233 35.“ 2:2 E: 3.22 5 5 0<> 33 88.2 > 252 25-2-2 :22 25-0-2 52 25-0-2 22.5 ma 225m 82 922305 32205 32288 9,2205 2,2205 8,230.: < 95 m 3228: 32205 32288 32205 $228: 32288 < 35 m 3228: 32288 32288 32303 2,2205 2,2388 m 95 < 32208 32288 32288 32288 32288 32388 m 95 < 2825 250.38% an 322.2555 202 mead-2m mo 50228580 80:23:00 fie 033. 528%? 222 $22 222 222 22.2 22.: 222 22.2 222 2:2 222 22 N82” 222 222 822 N82. 222 222 N22 28:: N2: 222 22 2 2 22.2 222 2:2 822 222.0 2.5 2 882 $22 222 222 E22 222 322 2.22 52 822 :22 53 882 28.2 222 222 22.2 222 :22 22 28.2 822 :22 S: 2 2 22.2 82 2:2 2:2 13 222 822- 222 32 2222 22.22 82.2- 22.2- 22.22 220 22: 232 222 oz: «220 222 822 222 222 $222 «22 222 222 222 222 22.2 22.2 232 22.: 222 5 2 0<> 33 89.2 > 222 25-2-2 222 25-5-2 3:2 25-0-2 2.290 >2.0 mm 222.2 222 8.8.2. 222 S2 2222 2228 82.2- 22.:- 222 220 82: 232 2:2 2:: 2220 22% 822 222 252 2222 22.2 222 222 222 222 22.2 22.2 2%: 22.: 222 2 2 0<> >52 22.2 > 222 25-2-2 822 25-5-2 222 25-0-2 2.26 >26 ma 22:32 83 03335 03385 36288 032:2: 039:2: 25205 <85 m 039:2: 038—88 033—86 «>332: 023—88 033—88 < 35 m 36205 02333 36288 2522: 3632: 2522: m 35 < 2532: aims—88 25288 25305 aims—88 023—83 m 95 < #qu o>=o~bom .3 vegan—magma “oz moan—am mo cemtquoU 62.5280 fic 2an 5339‘ 836 38.0 539% wmod ocmodh $36 $36.: vaNv hag.— 2‘34 :36 cmmg Emma wmvwfi @366 wood owfivé mead mums weed $2.3 onnd «mad nmmA— E o— 31% awn.— can; $34 1% owned 2 8.9 369% 95.0 33.: 3.3.3 Q36.» Sada 8:; mace; ngd 5o; wwhmd Nm_o.m @356 cafim mafia PEN a: N d emvd awmwd :Nad mwmmd 35$ E 0— mhhém wcmmg a2 m4 m2 m4 vnkN pom—«.30 aw 23¢ 88.? $86 83 «25 «$38 88.3- 22.3. at? 25 ~83 83... £86 23 25 53% ENE 885 Sea wsfiz 53 9A? 233 Sam 3m: $8.2 3%.» 22: mg: :fiz E 2 39 BS 8%.? > mm? 052-2 222 053-3 «22 25-0-2 «Ea—am 33¢ 38d $86 ~36 «25 23.8 £3: :36 3.: who 8%; 3.2 an; SE «25 03A 33 $26 23 wsfiz can: as? £86 £3 3»: £86 33 R86 83. 23A 3 2 BS 33 88% > SN? 25472 8%; 053-2 EB 25-93 I235 Eam- 3 295m 84 32288 3222: 32288 032:2: 2,2202 022:2: < 22 m 2522: 2,2305 26388 32288 3222: 03222: < 22 2 32205 039205 25388 32305 32305 2,2305 22::- 32205 32205 322020 32288 32305 2,222: m 85 < .52.: 0282.202 3 3222222me 82 moi—cam mo comm-89:00 602228 _.e 223- 262392 good 33.? cde vmod 5363 floods- max-.2- Ema-mo mmmmg own: $.36 33 wmofim gnu-N 836 mad mums. 22:” F226 m3...” cwmwd~ 3.32 3.de 52.3 o— awmwm mean; can; :3; wrung. o_ .H 9...... u. .15.. m. an 336 38d $.36 wmod vwmoém win-v “532.: ewfidv mum-w.— 332 3.226 am: SSW-N wavd 336 mum-N now: Read and wan-m mac—.2 mmmhs 33.: Sad 0— SSH comm; can; 05m.— 332-220 :23 282 28.2 :22 «222 22.5 28.2- 2322 23m 25 $32 822 28.2 M2: «25 :2:- 322 282 :3 2222 882 2x2 «23 R:- 322 E2: 322 22.2 25.2 232 2 2 u<> >52 32.3 > 322 222-2 222 22-2-2 222 22-0-2 «38.5 :32 282 282 :22 22.2 22.5 28.2- 2322 23m 25 3.: 822 28.2 83 226 :22 :22 88.2 :3 $22 882. 232 22.2 2:- 3w: 5.2: 222 32.2 892 222 2 2 SS >52 22.: > 32.2 22-2-2 222 22-2-2 222 22-0-2 2: 8.5”.— >25 mm can—am 85 3622: 023—05 033.38 2,6288 2622: 93335 < 25 m 023.2: 039:2: 023—88 2522: aims—88 03335 < 85 m 033.05 033.2: aims—ox» “56388 2522: 2522: m 95 < 033.05 033—88 033—83 3622: 023—88 aims—88 mSE < 48?: gauge-m 3 Rafi—$565 .02 8383 MO :85an0 62.588 fie 2an 598%?- memo-o wcmc-o Read 356 mag-3 33.5 MMQQN awe-S. m3"; 336 336 N34 emom-m ovum-N @366 m:.m awn-v mug-N .3.de bee-m Sac-2 awmhd aha-6 0N1: E o— way-mm anmmé 33.— ~93.— EUBEO ma Ewe-c Name-o téad mead RAE-m 3%.: Mam-m. NSdN 2.3”; vmmfi— bum-ad mmmg mmmwd ambim Qua-N6 mmm-N cmmvd cmwwé c236 $~.N 33.x «Eh-v QQVm-d ham-o E 2 Nun-mm Sum; mam.“ meg; lg $8.: 385 Va: 35 «2% 83.3 38.: 22.2 8...? E6 ”.32 SN: $85 a: «25 «82 ~82 52 :3 wzhz 8m:- afi: 52 :2 3»: 38.: 3ch ~83 3:: 3.2 a 2 Q<> 3.: 83m > 52 052-2 922 053-2 «22 25-0-2 2:. B 2955 :85 $86 386 :55 «23 ”:32 38.2. 3%.2 23“ MB $3; 835 386 $3 «25 82:“ ES 3S6 :3 $32 886 $35 8%.: 2:- 3»: RE: 33m 336 $5 2% a 2 SS 33 33% > 89: as; -2 32 25-92 as? 25-0-2 t 8.5% >25 mm 86 029:2: aims—oi 2,6288 2,6288 aims—0E 032:2: < 35 m 2622: 032:2: 23388 03335 2,622: 2,622: <02: m 36205 26205 033—88 3632: 2522: 023—05 m 35 < 029:2: 033—05 032:2: 033.88 2522: 033—2: m8£< .565 gag-aux an gammawcuma 82 3.95m mo scar—3800 603558 fie Bash 565%? mmaod memo-c- 66 N 6 6 god vam.w6N 83.5m- 6253. 63.: 866.— Namad 3. N 6 6 6:: hmmfm hams-N 6666 6 ch.m Vnwmd Sag-N n66w6 coma Nina-2 mamas 6va< www.: 0— ommvfim menA 62 m.— VE mg «.5200 >25 mm mama-o 2 No.6 V6666 eve-o She-wk. Eva: Rafi-N N acm-Su 36 fl ._ beam-o V366 vac.— wwamd Sofia 6666 .6 mac-m vwché Qua-N «mm-6N6 Ema 603.3 55.0 Vmwm 6 ~94 _ o— flee-mm ammng 3_ m4 m3 m4 38.0 386 3666 ave-o «22m mmcmdh ammo-E 33.3 omvdv MRO wacmg com: $36 3: «ZED mmmafl «mohm 2‘66 _nw.~ 3,32 own: 352 ES ES 3»: mace-2 mmows $36 3:: 2R2 E 2 U<> BOA man-mm > 3mm; Bid - a 022 25d - E 33; 25-0 - a 98...— 5 0385 $86 name-o “6666 956 «ZEm Sou-2. $8.: Emmi awe-me MRO wag; com: $36 3: «ZED 9mg...” SEN >266 Swd wvéaz cmmhé amt-N RN56 <36 36»: $8.2 Rows N636 vow-S 232 E 2 U<> >901— mandm > 53m.— BE-m - a 62m; 25-n— - a 334 25-0 - E 6.8,..— 5 nan—am 87 032:2: 02.2205 033—020 033.05 023—020 030202 < 85 m 030.205 020.205 023—05 02.239: 03.2305 023—05 < 25 0 033—05 033—05 0302020 030305 030305 033—05 m 85 < 020205 02.23020 039:2: 0322—05 032:2: 030-205 0 25 < .2065 02002.63. 3 60.3sz“me 32 8383 .20 cam-26800 60:50:00 2.6 030.6. 56:06an :36 626.6 6N666 N36 «Rm-3 mam-6N 6626 86.9» 32.6 wove-6 3666 666; cam-m Sew-N M6666 $6.2m wmmcé :mmd EKN .6 666.? 806.2 comm-Z V‘6V6 632$ E 0— Non-mm moan.— Nam; 63m.— ._0=u>aU 5:0 ma 366.6 owned 66666 N36 wmwmém moon-T 2326 SN: 63: 6666.6 66M66 N66.— ¢vwc.m amowN m6: .6 mbmfi m~mmé mum—.m R6VN6 mmwfi Mme-3 cum—.2 Gav-6 68.9 E o— 36.3 mom-m; can; 62m.— lg 885 285 28.5 :55 226.5 0868 22.2 33. «Ron 220 v82 8:; 2236 $2 2220 ~23 222 ~33 52 £22 22:. ES 22.5 23 7602 38.2 822 22.5 22.: 222 5 2 0<> 30.2 5.2 > 822 25-2-2 52 25-5-2 022 25-0-2 «Seam 3.: I ma 0.685 :35 3.85 285 28¢ 225 2222 $8.2. $2.2 :32 220 $23 82: :82 «:5 2250 29.2 282 28.5 23 2222 m2:- 882 223 22 302 :32 8.22 35.5 at: 222 5 2 0<> 305 22.: > 825 25-2-2 52 25-0-2 EB 25-0-2 X‘— tcomm 6.8% 0.685 88 32202 32202 32202 32288 32202 32202 < 82 m 32202 32208 32202 32202 32202 32202 < 22 m 32288 32202 32202 32288 32202 32202 m 82 < 32288 32288 32288 32202 32288 32288 m 82 < .0865 3689.635 .3 62226225 82 226526 .8 5823800 ”605228 5.6 833. 228692 736.6 6666.6 6 ~ 66 .6 666.6 6666.665 5666.66- 6666 .66 $6.: $32 ~666._ R6 6 .6 m2; $66.6 wax-6d 6666.6 6626 666:. 6666.6 66626 N666 K666— 6N6¢.6 6:6 .6 69%: E 2 666.66 66N6A h6_ 6 2 _S 6.2 NA «.5026 6.5..— 2666 6666.6 66 66 .6 N666 2 66.66 6666.3 66.2 .6 6666* 36 2 A 663; 6m66 .6 6662 6NNN.6 6666.N 6666.6 326.6 66666 366.6 V62 ~ .6 666.6 636.2 6628.: 366.6 636$ E 6— N66.66 66N6A N6 _ 6 ._ 665 6. _ 8:960 >30 66 82:0 285- 3.35 «85 22.5 2222 28.2- 22.2. 58.8 20 ~22 522 23.5 82 2220 22:2 222 822 ~22 2222 222. 2:2 255 2.22 222 32.2 28.2 22% 222 222 5 2 0<> 33 222 > 82.5 05-2-2 822 25-2-2 EB 25-0 - 2 .20ch 28:3 66 83:26 :22 285- 6.35 23. «222 38.2. 28.2 22.5 ~22-N 020 25: $32 530 $2 2220 88.2 52.2 222 83 2222 an? :2: :55 :22 222 22.2 52.2. 822 52.2 222 5 2 0<> 35.— 222 > 822 25-2-2 222 25-2-2 822 25-0-2 lg 2222 89 030205 030205 030283 020288 039205 033205 < 25 0 020205 030322 039288 039288 030305 039205 < 95 0 030205 030288 039288 030205 039205 030288 m 35< 03020.2 020205 020388 03028.20 03030.2 029205 mBfi < £025 0>20N20M .3 20202095me 82 838$ .20 80203800 60:50:00 2.2 035. 0220:2522. ameod owned «63.2 N35 wawmém 825.2- 23:2 3N: emf; 336 386 N2: avwcd 33:0. 2226 mad mane 3&3 3‘3 035. $2.: 82.: 23.6 80.2 E 2 35% SN? can; 023 lasagna? 38.0 38.0 $8.0 $0.0 $8.8 0:: 8%.: 333 mg: 32.2 33.0 am? 523 $30 33.0 $3 Sm: $02 $3.0 mm; 82.2 mm: $5.0 Gad E 02 26mm comm; 023 022 0.32505 886 $8.0. 33.2 305 azim 2%de good»- 222. .2. cmmdc MED Nmmmg 2mm: $3.2 ma: «ZED waofim ownhd 33.2 mmmN wERZ g: E 2” 53 $3 302 83.3 Vmomd on? .2 30.3 234 E 2 U<> BOA awmdm > SN: 0:22 - 2 80m; 0:2..Q - a 2:2 052.0.52 03:35. 500:: mm 0.955 Seed $.56- $86 $56 aZEm $3.32 vmooNh- «5:. .2. 336 MED NmmNA 0mm: 3.36 no: «ZED mmo_.m cvpd 88.2 NNQN 3602 0224. v: 2m 03 ~ .2 mod $32 33.2 Vmomd 03m .2 $2.2 ZRZ E 0— U<> BOA $03 > won: 002-2 - E 802 0:25 - a 22m; 0:26-52 #3 235 9O 032222 032222 032228 032222 032228 032228 < 35 0 032222 032222 032228 032228 032222 032228 < 022 m 032222 032222 032228 032222 032228 032228 m 32 < 032222 032222 032228 032222 032222 032228 m 022 < .2022 3200.202 .3 2022:2529 82 8:28am .20 28223800 ”2022280 2.2 038. 222823 mmcod ommod «68.2 N32 223 22:- 22.» new: 22: Some 228.2 83 $22 223 2.2.8 22 22.2. 222 32.0 2223 22.: 82.: 33% 92.2 E 2 85m $22 023 at? 3.202 3 2.35 88.0 28.2 23 :23: «comm- ‘82: 2.8.2 :22 23: 222.0 23 2.5m «~23 £86 23 £26 :22 Reg 23. E22 82.: 253 22.2 E 2 83.2 :2: 82.: ER: Essa 82.8.— 2 :23 23° 2.82 #3 «2% 5:: 22.: 32 ~52 25 2%.: EN: 286 22 «25 222 ~22 an; 22 $32 22.2 322 286 $3 3»: 28.x 325. 3:6 33 222 E 2 29 33 202 > 82.: 25.2.: 23 25-0-2 232 25-0-2 “Locum tho-m va o—maum 2:3 285 386 $3. «2% 22.2 :82 .82.: 222. 28 m2? :2: $36 $2 «25 23m 22 a»: :3 $32 233. $22 as? 22 .302 28.2 :3: 32S 22: 222 E 2 SS >52 22.2 >, 22.: 25-2-2 82.: 25-2-2 2:3 25-0-2 m 22:6 85 2 0.25am 91 032222 032222 032228 03220.2 032202 032222 < 8.2 m 032222 032202 032228 032222 032222 032222 < 022 m 032222 032222 032228 032222 032222 032222 m 8.2 < 032202 032222 032228 032222 032202 0322822 m 0:2 < 2822 03208-202 >2 2022:2225 82 moan—am mo 52.29200 60.22280 26 032.2. 22282?- 336 286 ESQ 6 03.0 53.5. h 23%.: ~Qmm.~ N mow-EV $3 .2 836 V366 3c.— wwmmd neawN QQQQ 6 macaw 595v «mamfi memd 236 83.3 schmd 3.3 6 2.8.2 2 22 2 286m Amman.— 32m; 336 $86 83.3 33”.: mag N Ammo. 3» m2: .— haaad we 3 6 N3.— vMomxn ovgd c356 a fin mgmé 882 mwmmd boo-m 239m— awmhd awn-n 6 £2: 22 2 32mm mmmm2 am 2 m2 N02 m2 , III-ll EUR—20 ma 835 285 282 22. 225 88.2 23”.» 232 222. 23 52 R22. :82 82 «25 222 222 2.2.2 23 wzaz 2:3. 2:2 222 32m 3»: 32.2, $2.» 222 “2...: 222 2 2 35 BS 22% > 22.: 22-2-2 822 223-2 , .22 22-0-2 1%; 225 $35 285 282 2% 2225 88.2 23.6 23.2 222. 25 52 R22 :32 22 «25 222 222 $22 22 2222 2:1. 2:2 222 $3 3»: $2.: 82.” 22.2 22: 322 2 2 2.5 33 22% > 2%.: 22-2-2 222 22-2-2 3:2 22-0 - 2 lulsssm 0 25 3 2.25m 92 033—05 3622: 2532: 033—88 aims—88 033.88 < 95 m 2522: 033—88 033—88 039:2: 03335 36335 <85 m 9532: 33238 058205 36288 aims—88 033.88 m3§< 03335 03335 25288 etc-205 033—88 aims—axe m8§< 48?: ”Swag-«om 3 @053»:me 82 mpg—95m no newt-88°C ”325:8 fie 2an £23.?- vavod memcd Ngcd mgd ~306— momafi N3€6 30¢ «NZ-fl mug; “586 on; omoad wmva Nabad VNBN $3: owe-NA VNVQG Km; :Nm.m fiend $.36 v2.6 3 0— fimvém emmmg hm _ m; 33; .093H. .3: ch- mm :36 wmmod QNQQS N36 224% 2.35m 3.2 6 mcodv 2% fig wove-M fleas o2: ONNN.m 3ch m6de 25.n- wmmoé :35 SK ~ 6 vac-V egg? 88.: ngd 3‘12 E 0— memfim mean.— Ne m4 of mg 3:950 >20 ma £35 885 ~82 an: «25 225 8:6- Skfi $2:- $6 «:2 8:; $86 $2 «25 Emma ".32 886 $3 msfiz SN? ”83 £56 58 3»: 38.2 $3.” $3 $3: Zaz 2 SS 33 83m > ca? 85.2 ”$2 25-92 ~22 25-0-2 .37. .6 a macaw god 3.86 286 3:. «.25 53;. man: 53 5.8 M5 av? an: 286 :2 ~25 ea: flag Mam; 5:“ wsfiz 52 88; 3&3 :3 .3»: 5; 8o:- ~m§ 33 352 2 93 BS mama > SN? 052-2 922 25-9-2 8:; 25-0-2 AU Eam- Ech min—am 93 032205 932288 25288 022:2: 032288 032288 < 85 m 032:2: Dims—oi 32286 2622: 32288 32288 < 22 2 022205 02222: 95388 032205 032288 25388 m35< 032:2: 03222: 032288 032288 032288 032285 m85< 2865 gauged 3 322.2585 82 mafia-mm no 28229200 6022528 26 033. 262332 336 $86 MN666 36.0 30566 33.5 «665$ $9; @232 336 R266 ~34 wwemd ownwd 62.66 6:5 2:6 mmamd Max-NW6 $66 $3.2 $2.6 awn-n6 6%.: E 0— wavdm mam.— $3.2 N034 20220 ma mowed $86 $666 956 RVm.Nm Emmé awn-66 3.in 5N3; Sam; K666 8v; No_o.m vmmod 6366 mmw.~ vm_a.m Emma” R666 56d vmmafi 386 R26 5: E 2 52mm can; 3;.— $34 [fling 823 $82 28.2 252 2222 22.2 2.8.: 22:- 222 25 N22 332 2222 RS 226 283 222 222 ~22 2222 222 2:2 ~23 ~22 222 $322 23.2 283 at.” 222 2 2 35 BS 22% > $22 22-2-2 2:2 22-2-2 ~22 220-2 3 295m 232 882 282 282 222 22.2 2.28- 23: 222- 28 2:2 2.22 28.2 :22 «25 Emma 822 88.2 282 2222 $22- 283 25.2 33” 322 28.2 22.2 25.2 23: 222 2 2 35 >62 53m > 222 22-2-2 2:2 22-2-2 ~22 22-0-2 .57. :0 an 29.2w 94 2,2322 2,2305 2,2288 32288 32288 32288 <35 m 022:2: 32286 32233 02232: 95238 32288 < 22 2 32222 32205 2,2288 2,2388 033—88 2,2288 m 35 < 32283 2,2288 32288 32288 032286 25288 m 85 < 48?: gauged 3 32222525 82 moafiam mo 2828820 ”322528 fie 033- 22220222.. mono-o memo-o 3626 Sod mag-we 33”.: «Hag-u 23.? avg; 336 V236 N3; Vmcmfi avg-N 2356 3:” 23nd mam-N mvmmd bee-m 38.n— mwmhd awn-m6 emf: E 0— wavdm awn; $3.2 NEW-2 [Illa-v.3” memo-o memo-o mags $5.0 mach-v0 33”.: MMQQN 23.? avg; 3226 $36 N34 imam-m ovN-wfi 2366 3:.- QVmé mag-N .3de Sod $22.2 amp-a amaze 09.: E 0— wag-mm mam.— $3.2 N03; SUB—:6 ma 82:. $82 2332 $3 «222 52m 222. 32.2 3.2 25 52 82.2 :82 SI «25 8:2 382 282 83 2222 $22 222 28.2 2.82 3m: «83 233 :22 a: 222 2 2 SS 322 23.2 > 33 22-2 - 2 2:3 22-2-2 323 22-2-2 1% 3&an 823 28.2. 23.2 232 «222 22.2 E; 33 $2: 25 as? 822 28.2 :3 «25 «83 222 2:2 2: 2222 332 882 :22 a? 322 82.» 283 2.23 23 222 2 2 SS 322 88.2 > 52 22-2-2 2:2 222.2 $2? 22-0-2 LI (Hts—6&0 Uflmufléam @@ 228$ 95 2,828: 2,828: aims—88 833—88 3828: 833—88 <35 m 95305 38388 38388 2,6205 £5288 £8388 < 82 m 9528: 3828: 85388 25288 83.0.22: aims—88 m 95 < 9528: 3838: 833—88 023—05 833—88 833—88 m 33 < .889: 838.38% 3 32818585 “oz main—Sm mo comm-89:00 683538 fic 835- fivfixfi< mcmod memo-o Mmoed 35d moon-3 haemS— MMQQN mmoév ave; Sam-o 336 «no; gem-m AVE-Wm 0356 ¢:.m 933V mmmmd vaNN-e boo-m #392 amp-a 3.3.6 31.: 2 31mm ¢mNmA $34 SEA 203:6 ma 335 $86 mged Eyed mack-4% 3342 MMQQN $93 35“; Road «636 N8.— VMcmd ovgd “:de a:.m m—Vmé mmaad mVNNG boo-m ~39? amp-a awn-ad 8?: 0— mow-mm mmmmé $34 NEW— EUEEO ma $86 $85 $86 Sod «2% 82.8 $3.: $2.» moi-m MB an? 83 286 $2 «23 ~82 SEN :36 8mm msfiz ~83- fimg Egg Nam :82 88.2 as; $63 2; :82 E 2 8; 33 ”8.: > ”82 258-2 2:2 035-2 ~22 25-0-2 3226 2.5 8 2958 $23 $85 as: Sod seam 83.8 28.: 2:8 2&2 8:6 8%; 88: £86 82 «25 22a $88 $86 82 wgz 5.3 5:: 8:6 :2 3»: Ex: 83% mag ”$6 2% E 2 SS 33 82.8 > SN? oar-TE 8:? 25-92 §2 25-0-2 '3 285m 96 03335 25238 023—88 3622: 022:2: aims—05 < 35 m 38205 33288 25286 25288 36388 023.88 < 25 m .565 grow-aux 3 605333me 82 moan—am .«o aomtdeoU 6255.8 66 Baa-w xxx—25¢. 023:2: 032:2: 033—83 2622: 039:2: 3622: m 35 < 033—05 3632: 25288 25205 «>633». 033—88 m 23 < $36 mowed $66 .6 636 Chem-mam 3.3..ch Emu-6m ohm-mm She.— wgad ~NN66 :64 «Neg-m vaN «‘2 6 wam 3566 ewmvd 666N6 «ma-v unmod— cmwm6_ RE 6 Q 03 E o— - AVG-mm van; ow _ m; 5 _ m4 lg Nvmod memo-o 3.66 6 636 aha-mam $3.63- E wvfin ohm-mm :2: wgad ~NN66 :6.“ $93” met-N RR: 6 wwo.m mwhcé Saw-m 666m 6 N36 mewég omwmdfi RE 6 S 02 E 0— 636m 3mm; ow _ w.— $~ m._ In] a? .30.: «a 286 $85 $86 3.3 «2% 38.8 28.9. at.“ 813- M5 2:2 32: R36 22 «25 as? “WEN 2&6 ”3m £32 3%.,- vawea S26 9.? 3w: «3.2 5:: $83 25.2 262 o. 9.5 33 23% > can; Ban-TE 2:2 22-9-2 22 3-0-2 F83< «23% mm 29:3 885 $85 $86 Sod «2% :8? 83% SEN 8mg M5 :3: e22 286 $2 «25 88a 52 886 R3 mzaz can; oz? and £3 3»: $8.: 88¢ $3 $3 262 2 35 BS 53% > $22 Ban-TE 2:2 25-92 822 82-0-2 :80 8: oh ea «Ea—am 97 3222: 032505 25288 32288 32205 32288 < 85 m 2,2205 25288 033.88 2,2305 32205 32305 < 25 m 033—05 2,2388 25388 25288 033—05 023—88 mgfi < 2,2205 2,2205 32288 033.05 32305 32388 m 25 < .0865 2.608.63— 3 63222525 82 moi—Sum no 5033800 6035.80 66 035. x6523 mace-6 cmmcd 66666 N36 wmwmdm mock-.7 .2326 mom-S cnwfig 3666 6366 Nae; 659m amend m6: 6 mhmd Ewmé mnmfim 86:6 636 awe—.3 82.: 336 omv.- 0. 356m man; can; 62m; 385m :6 owned N— 86 6m. 66 6 $56 Gem-5» ahemdm 6N2.» 666.?“ 82.— wmoog 66m 6 6 $6.— owhmfi N266 66666 636 Nan-N fined 62 ~ 6 Exam awnofi 336 MV6N6 02k. 2 mun-3 mean; 663; mtmg VNuN 2:930 an 33¢ :85 280 285 55.5 28.8 5:? 8%.: £33 080 m5: m8: 822 82 «230 832 28$ 8.2.5 23 £32 «£3. 88.~ 825 82 .3»: 82.2 a: 825 8.8 :82 5 2 0<> 33 8:2 > 083 25-2-2 8:; 25-0-2 as? 25-0-2 0.32.265 oEEam $85 285 $85 Sod «25 8.8.2 3.8.2 28.2 3.8 2R0 88.. 082 8:2 2: «230 $82 882 $25 $3 “0232 882 2%; $2.5 83 3m: 82.” 38+ $3 23 32 5 2 0<> 33 «2.2 > 882 25-2-2 882 25.0-2 ES 25-0-2 can—am 98 .89: gnaw-aux B con—2.2525 82 838% no 58528.80 683528 2.0 838.2. 298an 822.85 022.85 32288 32205 32388 823288 32388 823—88 823—88 82388 32338 ”52288 < 35 m m 35 < 3232: 823.2: 822.85 32205 823—88 823—88 3222: 822.82 32:85 822288 822.82 22388 < 22 m m 22 < 22.85 >26 8 2.28 88.5 882 83 88.28 88.2:- 512 822 :82 885 286 :3 88.2. ER 233 23 28.2- 282». 286 N2:- 882 88.2 233 .222 2 228 882 2:3 8:2 [3 :23 882. 88.8 $3 28.8 88.8 82.» 828 322 832 E86 83 882 322 38.8 :52 88+ :82 8:2 83. 88.2 88.: 3.82 83.2 2 8.2 M82 832 . 8:2 336 886 N356 mvod «28m 23.8 33.5 Non-V6 Smd MED mam; m5: 386 can; 2220 @382 memN N956 van-N 3222 $3.2 94m; wfiéd EA 222 28$ Rena 2.36 3K2” 222 2 U<> >901— Evém > can; 25-2 - a $3.2 25-2 - a 83.2 25-0 - E 898,—- 3: on. ma «Ea—am vaod ommod 336 Quad «ZEm mom-n.3— mommd .83 .2 wmwdc MED amt-:2 man: :36 22 «220 mummd 8de Quad ~86 3222 8.2- 882 E 8.8 282 3»: 8:2 83.x 383 one? 222 2 U<> BOA v3.9 > mean; 2.2.2 - a 323 255 - E 822 25-0 - E 58,—- 3.5 va oEEam 99 aims—05 039:2: 3822: 2532: 032:2: 33205 < 85 m 03335 25288 03,-3.on aims—88 25288 26288 < 35 m 2522: 033—88 033—2: 033—2: 033—2: 3632: m 25" 25205 023—88 023—88 033—88 aims—88 023.83 m3fi< $36 $86 28 6 $66 38.8 Nva .2 36m. N 25.5” 38.— :wmd «656 mm: 32 .m mehd babes mead 231g Nona-N mwvms 02.6 530.3 83.x Nam .Q 03.2 E o— 3 mmdm «www.— ow _ m; 5 ~ m4 EU ea 33d Nomad 28 6 N36 $8.8 avg .2 36%. N Sag-m «ewe; :wad Mb 36 m8.— nae _ .m mehd eggs mcafi 936 mogfi mmvmd @056 23.3 wocww when 6 93.3 E 2 3 86m memA cm _ m4 5 _ m.— 20 ea 48?: gauged E 3&3?sz “oz 838mm mo cam-"38°C 628880 fie 03¢.“- 530mg $85 385 $86 Sod 22m 33%; «33:- EEK 2me M5 ES ”3% :86 :3 «25 39% SEN :53 £3 mzzz 3%.... 08$ 35% $3 3»: $8.: 832 R36 «3.2 :fiz E 2 35 BS 292 > «22 Bad-E 2:2 aid-E 3:3 25-0-2 .8 a3 .30.! am 295m 323 885 35s m2; «25 232 83s a»; 32 M5 ES m5: 88¢ 82 «25 893 mafia 836 $2 wzhz $9: 8:; R23 :2 3w: :qu 5.3 3.36 $2 3.2 E 2 SS BS 51% > can; Baum-2 2:2 Quad-E §2 25-0-2 I3 «flea 100 32288 832288 83.0.32: 832:2: 832:8: 83.0.28: < 22 m 3228: 832.85 83228: 95288 32:85 2,232: < 22 m 83.0.28: 822:8: 2538: 2,238: 3238: 2,228: m 22 < 3828: 3.2288 8,238: 3238: 832:8: 2,228: m 85 <- 235 gauge-m >2 32222::me 8 Z 8.28% we 28288.80 683538 fie oSaH “£88292 mmmod $86. .336 mmod memdom ogmfin- 33:: 31mm mace.“ Nomad 3.36 oz: hmmvfi SNEN gees Nwo.m Emma chm.N 33.6 cow.”- NVmNS mmmwfi QNQQ mum-Z 0— cmmvdm mam.— cam; $202 1% amwod ommod 386 N36 wawmdm meg-.7 23.6 3N: cmwfifi 336 386 Nae.— mvwcd amwwfi 3:6 mhmd 2wmé mum—.0.“ ngvmd mmwfi $3.3 ommfi: Baud enqmg 0— 35.3 mommé cam.— ELF «to-Sm— ca 823 885 222 33 «2% 23.8 2%.: «23 23.:- 25 $22 835 $22 N2: «25 «$2 252 22.2 2; W222 232. 282 2&3 22m 322 38.2 222 222 2%.: 222 2 2 8; 33 222 > 882 22-2-2 222 22-2-2 ~22 22-0-2 2885 2 228.2 :2; 286 322 :52 ~25 2:22 2.82- E%.2 28.8 26 2:2 826 22.2 m2: 228 :8.»- EZ 38.2 :2 mzhz 882 222 882 23 3»: E2: 322 32.2 822 3.2 2 2 u<> 33 33% > 882 22-2-2 222 22-2-2 , 832 22-0-2 to 8.5m >25 mm 8.285 101 2,6303 2,8303 3.6303 03883 25388 25388 < 93 m eta-303 2,8303 03,8303 838303 03.8303 38303 < 22 m 38303 25303 38388 2,8303 2,8388 2,8388 m 22 < 2538: 38303 38388 85303 25303 833.03 m33< .889: grow-aux .3 333%:sz 82 8.95% «o acmtaEcU 62.3280 fie 838. 838593 m _ mod wwmod mgad mad meg-g wan 3.x. Nam-9N 03d 3 m3?— mcvad mass #83 3‘91” mas-m 3.de wcm.m owned chi-.3 N34 6 and awamd mm 36 «mm-:6 53.5 3 3 88.3 monA 33 m3 :3 m3 8.8.;— mm 38.0 memo-o- mas-Q mmod vam.wom 83.5m- bNNm-«g‘ 38mm Soc.— Nmmad 3.36 oz: hmmvd hams-N eagaé awed www.md Sum-N 2.5.0.6 coma NVmNc— mmmms 9N3; mum-Z E 3 ommv.mm mem._ can.— 823 885 886 ~38 «25 88.8 832. 23.» mom: who ca: 322. 886 83 «25 $82 $23 253 Ea 8:82 2%.... m5."- 886 an: 382 $2.: 82.: 32% 822 32 E 2 8; 33 35% > 882 22-2-2 832 22-2-2 at? 228-2 3.28 8 mafia 33¢ 28... £85 $3 225 $8.? :32: 38.: 823 $6 $22 835 2.86 :82 25 88.". 823 886 83. wzhz 355. «83 3.3 Rm.»- 3»: 88.: 835 5a.: Rm: _<\~z E 2 89 BS $23 > 322 22-2-2 332 22-2-2 2:2 22-8-2 2:3 :95 £30 ma «En—am 102 022:2: 022:2: 0202020 022:2: 022:88 0202020 < 22 m 022:2: 02020.: 022:2: 022:2: 022:2: 022:2: < 0:: m 022:2: 023—020 023—88 022:2: 023—020 02335 m 22 < 022:2: 022:2: 022:2: 022:2: 022:2: 022:2: m o::< .202: 02208-202 a: 3:232:35 82 838mm .20 28:29:00 60:52:80 :6 03.»:- 0:309? wwmod Vwmod mgcé mgd Nam-mm Rea-m: m~mm.m- www.mm meg: chm—.2 @036 5:.— avoflm oamo.m cc: 6 356 cmch 93%.— 3.2 d wmfim amvwfi moomé Nu mu 6 N36 2: 0— www.mm 3%.: 8%.: K: w: 200.28 .5202 Na mhmod wmmod $de :56 ONE}; m «Long-2- MNVM 6m. mow-mk- NmeA gem: 3.36 am: bmomd ommvd mused god :56 NEON SNNd in...” ace: .: amgé “.366 and 2: 2 www.mm can: can: mzm: .525 5.. a. ma 885 285 28.5 285 «225 «82.22 2:32- %32 80.2 25 822 32.2 236 22 «25 3‘2 882 225 E: £22 3%... 352 25.0 $3 3m: 32.: 3%.” 2:2 82: 222 5 2 9.9 23 22.2 > E? 25-2-2 222 25-92 EB 25-0-2 3.52225 2 222% 88.0 28... $8.0 285 «225 £222 2:82- %3.& 822 26 822 «32 23.0 22 «25 2.3.,” 083 32.0 23 msfiz as? 35? 825 32m 302 32.2 5.3 2.3.5 8a.: 222 5 2 9; 33 28.2 > END 222-2 8:: 25-9-2 2:: 25-0-2 3522.5 2 0.22am 103 022:2: 022:2: 0202020 0202020 022:020 0202020 < 02: m: 022:2: 0202020 0202020 022:020 022:020 022:020 m 0:: < 20:00: 02202-23: b: 02:22:23.5 :07: $588 :0 52.29800 6025200 :6 050:. 2053.3 owned «:86 369% $66 :mcmfiv anomdm Q36.» 8a.?” 02:: wmoo: 3036 $9: cwbmd mm:o.m mcbad 3:6 max-N KEN 92 ~ 6 emvd mwmed :mmad mvmmd 0:8 2: 0: mtém wcmm: 3:0: mtw: v~uN 202930 am 88.0 280 280 25.0 «225 £222 N222- 208.2 80.2 020 82.: 22.: 230 22 ‘0720 35m 882 22.0 23 0222 283 $52 202.0 «22 202 $8.2 3%.” 23.0 20.: 32 5 2 0<> 23 22.2 > can: 85-2-2 2:: 25-0-2 2:: 25-0-2 02:23:20 2 22:50 104 Appendix VII Summary Data for Refractive Index and Elemental Analysis Comparisons l. Refractive Index Only N = 2450 Included = 186 (7.6%) Excluded = 2264 (92.4%) Appendix Table 7.1: Summary of Refractive Index Data. 2. Elemental Comparisons a) Different Refractive Index N = 906 Inclusive = 63 Exclusive = 696 Inconclusive = 147 Appendix Table 7.2: Summary of Elemental Comparisons for Samples with Different Refractive Indices. b) Same Refractive Index N = 186 Inclusive = 20 Exclusive = 131 Inconclusive = 35 Appendix Table 7.3: Summary of Elemental Comparisons for Samples with Indistinguishable Refractive Indices. 105 c) Refractive Index Ignored N = 1092 Inclusive = 83 Exclusive = 827 Inconclusive = 182 Appendix Table 7.4: Summary of Elemental and Refractive Index Comparisons. 3. For all 2450 comparisons, Inclusive (RI & SEM-EDS) = 20 (0.8%) Exclusive (R1, or RI & SEM-EDS) = 2395 (97.8%) Inconclusive (RI & SEM-EDS) = 35 (1.4%) Appendix Table 7.5: Summary of All Comparisons. 106 Notes Chapter 1: Introduction ' Dabbs, M.G.D and BF. Pearson. 1972. Some physical properties of a large number of window glass specimens. Journal of Forensic Sciences 17(1): 70-78. " Reeve, V., J. Mathiesen and W. Fong. 1976. Elemental analysis by energy dispersive x- ray: a significant factor in the forensic analysis of glass. Journal of Forensic Sciences 21(2): 291-306. '" Miller, ET. 1982. Forensic glass comparisons. In Forensic Science Handbook, ed. R. Saferstein. Englewood Cliffs, NJ: Prentice-Hall Inc. " Ibid. Chapter 2: Scanning Electron Microscopy m the Analysis of Glass V PFG. (1999). Window glass. About glass http://www.pfg.co.za/ about_glass_window.asp (29 September 2000). "‘ Saint Gobain Glass. ( ). Float glass. Glass teach-ins http://www.dockrellglass.ie /prod/teachin/float.htm (29 September 2000). V" PFG. (1999). Window glass. About glass http://www.pfg.co.za/ about _glass_window.asp (29 September 2000). V‘“ Saint Gobain Glass. ( ). Float glass. Glass teach-ins http://www.dockrellglass.ie /prod/teachin/float.htm (29 September 2000). "‘ Reeve, V., J. Mathiesen and W. Fong. 1976. Elemental analysis by energy dispersive x- ray: a significant factor in the forensic analysis of glass. Journal of Forensic Sciences 21(2): 291-306. Chapter 3: Review of Literature " Brown, G.A. 1985. Factors affecting the refractive index distribution of window glass. Journal of Forensic Sciences 30(3): 806-813. "‘ Ibid. "“ Hickman, D. 1981. A classification scheme for glass. Forensic Science International, no. 17: 265-281. "‘“ Koons RD. and J. Buscaglia. 1999. The forensic significance of glass composition and refractive index measurements. Journal of Forensic Sciences 44(3): 496-503. ’“V Ibid. "V Andrasko J. and AC Maehly. 1978. The discrimination between samples of window glass by combining physical and chemical techniques. Journal of Forensic Sciences 23(2):250-262. “i Ibid. xvii Ibid. Reeve, V., J. Mathiesen and W. Fong. 1976. Elemental analysis by energy dispersive x- ray: a significant factor in the forensic analysis of glass. Journal of Forensic Sciences 21(2): 291-306. 107 ""‘ Brown, G.A. 1985. Factors affecting the refractive index distribution of window glass. Journal of Forensic Sciences 30(3): 806-813. "" Andrasko J. and A.C. Maehly. 1978. The discrimination between samples of window glass by combining physical and chemical techniques. Journal of Forensic Sciences 23(2):250-262. ""‘ Reeve, V., J. Mathiesen and W. Fong. 1976. Elemental analysis by energy dispersive x-ray: a significant factor in the forensic analysis of glass. Journal of Forensic Sciences 21(2): 291-306. Cypter 4: Development of Suitable SEM-EDS Operating Parameters “ii Ary D., Jacobs LC. 1976. Introduction to Statistics: purposes and procedures. Winston NYzHolt Rinehart. C_h2_tDter 5: Conclusions_ and Discussion “i“ Saint Gobain Vitrage. ( ). Glass Manufacture. Fabrication du verre http:// www.saint-gobain-vitrage.com/english/manufacture/fr_fab.htrn (3 April 2001). ”“V Ibid. x“ Reeve, V., J. Mathiesen and W. Fong. 1976. Elemental analysis by energy dispersive x-ray: a significant factor in the forensic analysis of glass. Journal of Forensic Sciences 21(2): 291-306. “Vi Advanstar Communications. (2001). A guide to inductively coupled plasma mass spectrometry. Spectroscopy. http://www.spectroscopymag.com/articles/Ol03_articles /0103 _poster/0103 _poster.html (3 April 2001). “V“ Parouchais T., et al. 1996. The analysis of small glass fragments using inductively coupled plasma mass spectrometry. Journal of Forensic Science 41(3): 351-360. 108 Bibliography Advanstar Communications. (2001). A guide to inductively coupled plasma mass spectrometry. Spectroscopy. http://www.spectroscopymag.com/articles /0103_articles/0103 _poster/0103 _poster.html (3 April 2001). Andrasko J. and A.C. Maehly. 1978. The discrimination between samples of window glass by combining physical and chemical techniques. Journal of Forensic Sciences 23(2):250-262. Ary D., Jacobs LC. 1976. Introduction to Statistics: Purposes and Procedures. Winston NY: Holt Rinehart. Brown, G.A. 1985. Factors affecting the refractive index distribution of window glass. Journal of Forensic Sciences 30(3): 806-813. Cooper, BE. 1969. Statistics for Experimentalists. New York: Pergarnon Press. Dabbs, M.G.D and BF. Pearson. 1972. Some physical properties of a large number of window glass specimens. Journal of Forensic Sciences 17(1): 70-78. Dudley, R.J., et al. 1980. The discrimination and classification of small fragments of window and non-window glasses using energy dispersive x-ray fluorescence spectrometry. X-ray Spectrometry 9(3): 119- 122. F legler, S.L., J .W. Heckrnan, and KL. Klomparens. 1993. Scanning and Transmission Electron Microscopy: An Introduction. New York: Oxford University Press. Goldstein, J .I. and H. Yakowitz, eds. 1975. Practical Scanning Electron Microscopy, Electron And Ion Microprobe Analysis. New York: Plenum Press. Hickman, D. 1981. A classification scheme for glass. Forensic Science International, no. 1 7: 265 -28 1 . Hickman, D.A., G. Harbottle, and E.V. Sayne. 1983. The selection of the best elemental variables for the classification of glass samples. Forensic Science International, no. 23:189-212. Koons RD. and J. Buscaglia. 1999. The forensic significance of glass composition and refractive index measurements. Journal of Forensic Sciences 44(3): 496-503. Lloyd, J .B.F . 1981. Fluorescence spectrometry in the identification and discrimination of float and other surfaces on window glasses. Journal of Forensic Sciences 26(2): 325-342. 109 Parouchais T., et a1. 1996. The analysis of small glass fragments using inductively coupled plasma mass spectrometry. Journal of Forensic Science 41(3): 351-360. PFG. (1999). Window glass. About glass http://www.pfg.co.za/about_glass_window.asp (29 September 2000). Reeve, V., J. Mathiesen and W. Fong. 1976. Elemental analysis by energy dispersive x- ray: a significant factor in the forensic analysis of glass. Journal of Forensic Sciences 21(2): 291-306. Saint Gobain Glass. ( ). Float glass. Glass teach-ins http://www.dockrellglass.ie /prod/teachin/float.htm (29 September 2000). Saint Gobain Vitrage. ( ). Glass Manufacture. Fabrication du verre http:// www.saint-gobain-vitrage.com/english/manufacture/fr_fab.htrn (3 April 2001). 110 IIIIIIIIIIIIIIIIIIIII ll'l'lllllllllllIt'll