CH. VIII.} PHOTO MICROGRAPHY. 205 



PHOTOGRAPHING NATURAL HISTORY SPECIMENS WITH A VERTICAL 



CAMERA.* 



§ 349. For most natural history specimens it is inconvenient, and for 

 many impossible, to use a horizontal camera and to raise the objects 

 in a vertical position. In order to have the objects horizontal either a 

 mirror must be used or preferably the camera itself may be so arranged 

 that it may be put in a vertical position. 



For the last twenty years such a camera has been in use in the Ana- 

 tomical Department of Cornell University for photographing all kinds 

 of specimens ; among these, fresh brains, and hardened brains have 

 been photographed without the slightest injury to them. Furthermore, 

 as many specimens are so delicate that they will not support their own 

 weight, they may be photographed under alcohol or water with a ver- 

 tical camera and the result will be satisfactory as a photograph and 

 harmless to the specimen. 



A great field is also open for obtaining life-like portraits of water 

 animals. Freshly killed or etherized animals are put into a vessel of 

 water with a contrasting back ground and arranged as desired then 

 photographed. The fins have something of their natural appearance 

 and the gills of branchiate salamanders float out in the water in a 

 natural way. In case the fish tends to float in the water a little mer- 

 cury injected into the abdomen or intestine will serve as ballast. 



The photographs obtainable in water are almost if not quite as sharp 

 as those made in air. Even the corrugations on the scales of such 

 fishes as the sucker (Catostomus teres) show with great clearness. In- 

 deed so good are the results that excellent fine tint, half tone plates 

 may be produced from the pictures thus made, also excellent photo- 

 gravures. In those cases, as in anatomical preparations, where the 

 photograph rarely answers the requirements of a scientific figure, still 

 a photograph serves as a most admirable basis for a scientific figure. 

 The photograph is made of the desired size and all the parts are in 

 correct proportion and in the correct relative position. From this 

 photographic picture may be traced all the outlines upon the drawing 

 paper, and the artist can devote his whole time and energy to giving the 

 proper expression without the tedious labor of making measurements. 



" While the use of photography for outlines as bases for figures di- 



*Papers on this subject were given by the writer at the meeting of the American 

 Association for the Advancement of Science in 1879, and at the meeting of the 

 Society of Naturalists of the eastern United States in 1883 ; and in Science, Vol. 

 Ill, pp. 443. 444- 



