August 23, 1950 
Office of the Quartermaster General, 
Research and Development Branch, 
Department of the Army, 
Washington 25, D. C. 
Attention: Dr. Ray Trichler 
Gentlemen: 
I am writing to inform you that in connection with a 
recent field expedition I made on behalf of the Smithsonian 
Institution to collect specimens of birds and to study their 
distribution in remote jungle areas in Panama, I had as part 
of my equipment one of the hand-operated Engstrum Guns, 
issued by Mr. Paul Engstrum, for experimental testing, and 
the #2 Insecticide. The latter was given to me for testing 
through Dr. H. G. Eederer of the Biological Laboratory, R. 
M. Hollingshead Corporation. 
In the course of this work, a base was established in 
the small village of Chiman on the Pacific Coast of the Republic 
of Panama, about 90 miles east of Panama City, and from here 
I worked back into the interior by dugout canoe to the head of 
that type of travel, and then walked in with porters to the isolated 
mountain range known as the Serrama de Maje. Near the coast, 
the party was quartered in small native houses of various types, 
while at our inland camps, we constructed ramadas, these being 
shelters made of poles with thatched roof of palm leaves, and 
completely open sides. 
In such work, the two principal concerns with insects 
are (l) the health of the workers, and (2) the protection of our 
specimens and equipment from insect damage, particularly 
from ants. We lived for most of the time in shelters that were 
completely unprotected. 
