Auk 
April 
252 Correspondence. 
Formalin is now easily obtained, is not expensive, and is neither 
inflammable, nor has it any unpleasant smell. The vapor of formalin is 
a powerful germicide, according to recent experiments; and only a few 
minutes are required for its complete diffusion and the disinfection of a 
room of moderate size. It is said to have no action on animal pigments. 
A recent article on ‘ The Disinfection of Books by means of the Vapor 
of Formalin’ concludes as follows: 
‘1. Books can be disinfected in a closed space, simply by vapor of 
commercial formalin by using 1 cc. of formalin to 300 cc. or less of air. 
2. The vapor of formalin is rapid in its disinfectant action. The effect 
produced in the first fifteen minutes is practically equivalent to that 
observed after twenty-four hours. 
3. An increase in the amount of air to each cc. of formalin is not 
counterbalanced by an increase in the length of time of exposure. 
4. In case the disinfection has been incomplete, the vitality of the 
organisms has been so weakened that they survive only if transferred ina 
few hours to media suitable for their development. 
5. The use of vapor of formalin is not detrimental as far as observed 
in any manner tothe books, nor is it objectionable to the operator beyond 
a temporary irritation of the nose and eyes, somewhat similiar to that 
produced by ammonia.” 
Having no infested bird-skins, and being unable to find any Dermestes, 
or other beetles, I can only speak of its effect on the ‘ Clothes Moth’ and 
larve. A number of the moths and caterpillars with the material on 
which they were feeding, were put in the trays of a museum case, 
about 54 cu. ft. in capacity; and in the middle tray a saucer holding a 
couple of teaspoonfuls of commercial formalin. The can was kept shut 
for an interval varying from two hours to five minutes, the experiment 
being repeated a number of times. Exposure to the vapor for half an 
hour or more was fatal to both moths and larve; while often fifteen 
minutes in the case was enough to kill the moth, and less frequently the 
caterpillers as well. A longer time may be needed for the formalin vapor 
to reach and destroy insects which are not on the outside of the speci- 
mens, and possibly the disinfection may be found not to be only superfi- 
cial at best. 
If the alcholic solution — ‘ holzine’—can be obtained it would doubt- 
less be better than ‘formaline,’ which is the aqueous solution of formic 
aldehyde. 
I hope others will try this disinfectant, and report its success; for it 
would certainly be a gain if it were necessary to ‘ quarantine’ our collec- 
tions for only an hour or two, and without the odor and risk of fire, 
which now accompany the process. 
Respectfully yours, 
ARTHUR P. CHADBOURNE, 
225 Marlborough St., Boston, Mass. 
