PROPHYLAXIS OF MALARIA* 
69 
it has given very excellent results. He quotes two instances given 
by Le Prince, which are so striking that I will give them in his own 
words. He says: 
The first systematic application of mosquito catching within habitations as 
a prophylactic measure against malaria, in so far as I have been able to learn, 
was made in the Canal Zone, in April, 1908, at a camp near Cocoli. The camp, 
composed of unscreened tents, was to be maintained only about five months, 
and it was not thought practicable to incur the great expenditure involved in 
a thorough antimalarial campaign. When the camp was first established, as 
many as 30 anophelines could be seen in a tent in the daytime, and many 
more after dark. One man -was employed to kill the mosquitoes in these 
tents. He worked from 0 to 11 in the morning and from 1 to 5 in the after¬ 
noon. In the four and a half months of this camp’s existence the malaria 
incidence was a little over 1 per cent per week. 
Another remarkable instance is described by Le Prince in Ross’s “ The Pre¬ 
vention of Malaria.” In June, 1908, several hundred United States marines 
were quartered for about eight weeks on a hill near Panama, known as Diablo 
Hill. During this period the malaria incidence among the marines was 14 per 
cent per week. In May, 1909, some living cars were located on the same hill. 
The anopheline breeding was just as it has been at the time the marines camped 
there. From the first week in May to the end of November, in the rainy sea¬ 
son. when malaria incidence is high in Panama, only four cases of malaria 
occurred among the 40 laborers occupying these cars, a weekly incidence of 
about 0.3 per cent. The difference was due to having a man devote half an hour 
a day to the destruction of the anophelines found in these cars at a cost of 
5 cents a day for the labor.” 
The above illustrations demonstrate that mosquito catching is 
capable of keeping the malaria incidence down to a very low figure 
even in hotbeds of the disease, and indicates how valuable a method 
this would be in the military service, where it could so easily be 
adopted. 
The mosquitoes are caught with the chloroform tube already de¬ 
scribed in Chapter II, although Orenstein recommends that instead 
of cotton at the bottom of the tube to receive the chloroform a 
layer of short lengths of rubber bands covered with a plug of cotton 
be placed at the bottom of the tube and saturated with chloroform. 
In addition to the killing tube the mosquito hunter is also furnished 
with an ordinary u flv swatter” and instructed to catch or “swat” 
every mosquito observed. The method of catching mosquitoes with 
the tube has already been described (Chapter II, p. —), and the mos¬ 
quitoes should be searched for in dark corners of rooms, in closets, 
along baseboards, beneath sinks and toilet fixtures, behind pictures, 
and in tents, along the ridgepole, in the corners behind clothing, and 
beneath cots and mosquito nets. The “ fly swatter ” is especially use¬ 
ful in killing the mosquitoes frequently observed on the outside and 
inside of screenings on verandas, doors, and windows. At Camp 
Stotsenberg, during the rainy reason, the outside of the window 
screens of the hospital and other buildings was frequently the resting 
