MEMORANDUM 
January 14, 1941, 
Mr. Wishard at the National Geographic Society after 
examination of my Costa Rican film says that the trouble is 
due to verichrome film. I should change to panchromatic film. 
Their men use Panatomic X. He also tells me that for their 
work they use only two filters K 2 and A. He recommends as a 
new camera the Zeiss Ikon Maximar B which takes a picture 
3-V2" X 4-3/4". 
A, Wetmore, 
Assistant Secretary, 
Ip 
