216 ANNUAL KEPORT SMITHSONIAN INSTITUTION, 193 9 



which modern scientific methods, and more specifically the application 

 of physical techniques, are playing in the unending war against crime. 

 The contrast between present-day methods embodying scientific 

 principles and those of an earlier era can be summed up no more 

 aptly than in the amusing but pointed exclamation, "Shades of Wyatt 

 Earp ! The old boy would turn over in his grave if he could hear 

 that," which a western officer w^as heard to make upon having the 

 advantages of spectrographic examination pointed out to him. 



While the spectrograph has been a familiar instrument in physical 

 and chemical laboratories throughout the world for many years, be- 

 cause of its fundamental importance in these sciences, consideration 

 of its possible application in crime-detection problems is relatively 

 recent. Cognizant of the invaluable assistance already gained from 

 scientific methods, and in line with its policy of exploring new 

 methods of attack, the Federal Bureau of Investigation some time 

 ago installed such an instrument in its technical laboratory in an 

 effort to ascertain the extent of its application to law-enforcement 

 work. The rapidly increasing number of instances in which it has 

 proved of value already indicates that there is a definite place for 

 it in this field, in spite of the fact that only the surface has been 

 scratched in exploring its possibilities. 



Although the instance cited above indicates spectrographic results 

 to be important from an affirmative evidentiary standpoint, it should 

 be noted that its results may be equally valuable purely from an 

 investigative standpoint as exemplified in the following case in which 

 an extortionist identified the proposed pay-off spot by the simple 

 process of painting a rock white at the desired location. During the 

 subsequent investigation, special agents of the Federal Bureau of 

 Investigation removed small flakes of this white paint and submitted 

 them to the Bureau's technical laboratory together with specimens 

 of white paint recovered from the home of a suspect. A spectro- 

 graphic analysis of the paint used by the extortionist indicated it 

 to be of a zinc base type whereas a similar analysis of the suspected 

 paint showed it to possess a titanium base, and therefore to be not 

 identical with the paint removed from the rock, a result which could 

 have been obtained only with difficulty, if at all, by the usual chemical 

 procedures because of the limited amount of material available for 

 analysis. 



Although the science of physics has contributed in some manner 

 or other to almost every branch of crime detection, it is difficult, be- 

 cause of the overlapping nature of the various sciences today, to 

 isolate and attribute specific improvements or techniques to physics 

 alone or to any other single branch of scientific endeavor, such im- 

 provements or techniques in most instances having been rather the 



