76 
PROPHYLAXIS OF MALARIA. 
of protection from the bites of these insects. In the military service 
the ideal mosquito net would be one that could be used over the bed 
while the troops are in permanent barracks, and within the shelter 
tent when in the field. Such a mosquito net has been devised by Capt 
Yedder, of the United States Army Medical Corps, and has been 
adopted by the Quartermaster’s Department for issue to the troops. 
It can be easily folded and carried in the pack when troops are in the 
field and, if properly made., will undoubtedly be found to be a most 
valuable aid in preventing mosquito-borne diseases in an army during 
active operations, besides greatly increasing the comfort of the troops 
when campaigning in regions where mosquitoes abound. 
In barracks where mosquito nets are used there should be a nightly 
inspection of the nets after taps, to insure their being used by every 
man and that they are being properly used. Care should be taken 
to see that each net is tucked under the mattress, instead of hanging 
loosely around the bed, as otherwise mosquitoes easily gain entrance 
by crawling or flying between the net and the mattress. During the 
day the mosquito net should be preferably taken down and folded 
up on the bed, but may be either tucked in beneath the mattress if 
the bed is made up or folded over on the portion suspended between 
the uprights. The greatest care should be taken to keep the net in 
repair, all holes being darned as soon as they are discovered. 
Head nets and gloves .—Head nets and gloves are absolutely neces¬ 
sary in many regions if one is camping or hunting, and the same is 
true when troops are in the field in such localities. The Quarter¬ 
master’s Department of the Army issues a very good head net, so 
fashioned as to fit over the campaign hat, and this will be found of 
the greatest service, especially to the men on guard, and their use 
should be insisted upon in malarial localities. I am convinced that 
if a head net had been worn by men on guard at several of the posts 
in the Philippines it would have greatly reduced the amount of 
malaria, for many cases of infection occurred that could be traced 
to the soldiers being severely bitten during guard duty. 
The use of odorous substances on the skin .—Various substances 
have been recommended for protecting the skin from the bites of 
mosquitoes. Among the best may be mentioned the oils of citronella, 
eucalyptus, pennyroyal, anise, camphor, vaseline, and kerosene. 
As a rule the slight protection afforded by these substances has not 
led to any extensive use of them in the military service, but there may 
be circumstances in which the use of one or the other of them may 
prove of value. Such an instance is quoted by Howard, 36 who states 
that Dr. AY. H. Dade, United States Army, found a mixture of one 
part of bergamot oil to sixteen parts of kerosene very efficacious in 
preventing mosquito bites when smeared on the skin, and that this 
