14 BULLETIN 986, U. S. DEPARTMENT OF AGRICULTURE. 
attacks than topped shoes. This the writer demonstrated himself 
many times. High-top shoes or, better yet, laced boots, gave a con- 
siderable amount of protection. On several occasions the writer was 
accompanied on his trips by Mr. W. W. Diehl, of the Bureau of 
Plant Industry. Mr. Dieh] demonstrated well how the body could 
be protected by wearing topped shoes and spiral puttees. The latter 
were wrapped tightly about the calves and gave almost complete 
protection. 
Concerning this method, however, there are two objections: First, 
it causes a considerable discomfort to wear such tight and rather 
heavy clothing during the hot season, and second, if the individual 
sits down, reclines, or brings the hands in frequent contact with the 
surface of the ground, the chiggers will attack in considerable 
numbers. 
Another method of gaining protection which has been tried in the 
past is to use some repellent on the skin or on the clothing. Sulphur 
has long been recommended for this purpose and Dr. Chittenden 
(2, p. 5) calls it “a sovereign remedy for mites.” <A test of its 
efficacy was made as follows: | 
At East Falls Church, Va., on July 25, 1919, before going into a 
well-known infested area, the left stocking and the lower part of the 
underwear on the left leg were dusted inside and out with flowers 
of sulphur. The sulphur was applied by the “ pinch method,” fol- 
lowed by rubbing. About a tablespoonful was used. From 2.30 p. m. 
to 4.20 p. m. there was exposure to attack in the infested area, and 
at the end of this time a laboratory examination was made. On the 
calf and ankle of the untreated leg several chiggers were observed, 
all unattached and running about very energetically. On the calf 
and ankle of the sulphured leg not a single chigger was found. Later, 
at 9.45 p. m., another examination was made. The untreated leg 
had a large number of chiggers attached, these being distributed 
from the ankle to the hip. The treated leg did not have a single 
chigger attached. 7 
On August 4, 1919, a test was made to see if a dusting of sulphur 
on both sides of the clothing was any more efficacious than dusting 
on one side only. The stocking and underwear below the knee on 
the left leg were sulphured by the “ pinch method,” both inside and 
out. The stocking and underwear below the knee on the right side 
were sulphured as before, but only on the outside. 
At 3.30 p. m., after exposure, an examination of both legs failed 
to reveal a single chigger. It was noticed also that there was much 
more sulphur adhering to the left leg than to the right. A later 
examination at 11.30 a. m. the next day failed to reveal a single 
chigger on the left leg and only one chigger wheal on the right, this 
being near the instep of the foot. 
