CHAPTER II. 



PHOTOGRAPHY. 



In all pharmacological laboratories (especially if any 

 original work is being done) circumstances often arise in 

 which it may be desirable to do some one or more forms of 

 photographic work. In all laboratories where the expense 

 can be afforded the author recommends that a dark room 

 and a good photographic outfit be provided. 



The present chapter is intended only to very briefly dis- 

 cuss a few of the more fundamental processes which may 

 be of the widest applicability in the laboratory. These pro- 

 cesses involve particularly the routine production of nega- 

 tives and prints, developing, fixing, printing, etc., the mak- 

 ing of blue-prints, lantern slides, copying, etc. A full de- 

 scription of the theory and finer details of photographic 

 work is not attempted here since those who will most care to 

 make use of the suggestions offered in this chapter will 

 already have had more or less experience in photographic 

 work, especially in the making of ordinary photographs with 

 a hand camera, etc. 



For several years the author has used in the laboratory 

 an ordinary view camera (8x10 size). The lens used with 

 the camera is a Bausch and Lomb, protar VII A, size 5x7. 

 Either the front or the back half of the lens can be used 

 separately and will then cover a somewhat larger area on 

 the plate. This outfit has been very satisfactory for labora- 

 tory purposes, especially for copying and lantern slide mak- 

 ing. There are many forms of lenses and cameras on the 

 market, the majority of which are not suited for laboratory 

 purposes. It is best to buy these articles only from well 

 established and reliable firms which will supply outfits 

 properly adapted for doing exactly the work which the 



