I'lCrURf: TR.IXSMISSIOX Oll-R ir.lJ.I'IIOM-. I.IM.S 



I"li;i.l>S ()!■ I'SKFULNKSS 



211 



Thf tieUls in wliirli iliitrirall\ transmittfcl piiluris may l)f of 

 greatest service are those in whirli it is desired to transmit informa- 

 tion which ran only t)e conve>ed eUcctively, or at all, by an ap[H'a! 

 to vision. Illustrations of cases where an ade(|uate verbal descrip^ 

 tion is almost impossible, are portraits, as, for instance, of criminals 









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Fig. 2() — Electrically transinittod fingerprint 



or missing individuals; drawings, such as details of mechanical parts, 

 weather maps, military maps, or other representations of transient 

 conditions. 



The value of electricalK- transmitted pictures in connection with 

 police work has been recognized from the earliest days of experi- 

 ments in the transmission of pictures. Besides the transmission of 

 portraits of wanted individuals to distant points, there is now pos- 

 sible the transmission of finger prints. Some of the possibilities of 

 the latter were demonstrated over the New York-Chicago picture 

 sending circuit at the time of the Democratic Convention, July, 

 1924. The Police Department of New York selected the finger- 

 print of a criminal whose complete identification data were on file 

 in the Police Department in Chicago. This single fingerprint, 

 together with a code description of the prints of all the fingers, was 



