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KANSAS UNIVERSITY SCIENCE BULLETIN. 



tubes; two wash bottles, one containing chemically pure am- 

 monium hydroxide, the other with chemically pure hydro- 

 chloric acid ; and two drying towers filled with calcium chloride 

 to extract all moisture from the air. 



Figure 2. 



A vertical camera designed especially for making photographs of 



large delicate objects. By means of a clear-glass background shadows 



are eliminated. This camera was designed and made by Dr. S. W. 

 Williston. 



