SCIENCE IN THE INDUSTRIAL WORLD 



earth is imperishably recorded by spectrum photog- 

 raphy. All knowledge revealed by the ultra-violet 

 rays of the spectrum has been acquired by use of the 

 photographic plate, since the extremely short length 

 of the waves renders them invisible to the human eye. 



The value and use in medicine and surgery of pho- 

 tographs taken with the Rontgen ray, have already 

 been described. More recently the kinematograph 

 has been adopted in the study of diseases, especially 

 those of nervous origin. By its means faithful records 

 of the abnormal play of features, convulsive move- 

 ments, strange attitudes, faulty gait, etc., may be 

 obtained, the careful observation and study of which 

 when thrown on the screen has proved of invaluable 

 aid and service to the physician. The mystery of the 

 background of the eye was finally solved by stereo- 

 photography. The use of microphotography in obtain- 

 ing records of minute organisms and their development 

 is only another of the many ways in which photog- 

 raphy has become indispensable to the pathologist. 



In zoology and botany the camera has revolution- 

 ized all methods of observation and research. The 

 photography of animals and plants in their natural 

 environment is a most valuable means of investiga- 

 tion and information and not of mere illustration, as 

 some may suppose. For these same purposes the kine- 

 matograph is being put more and more to practical 

 use by the zoologist. Microphotography is rarely 

 absent from the work of the botanist, and from it 

 results of enormous practical and economic value have 

 been obtained in the department of plant pathology. 



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