506 
Combating Lousiness 
( b) Experiments with Insects present on Clothing or Man. 
1. On Verminous clothing. 
Ref. 
No. 
Insecticide tested 
(vapour or contact) 
Experimental conditions 
Result 
Authority 
240 
Ammonia, 25 % 
4 litres evaporated by Pliigge 
lamp into 3j cbm. space of 
Amsterdam disinfection wag¬ 
gon 
(5 litres evaporated in 2f hrs 
by burning 1100 c.c. of spirit, 
temperature attaining 35° C. 
in space) 
Nits killed in 1-3 hrs 
S. 
241 
>> »5 
Sprinkled on dry clothes in 
box (mattresses were treated 
4 hrs) 
Nits and lice killed in 1 hr 
P. 
242 
J J 
Clothes soaked therewith, roll¬ 
ed up in cloth and placed on 
floor 
Lice survived 1 hr exposure 
Z. 
243 
Benzine 
40-50 c.c. sprayed on clothes 
in metal boxes 
All lice “dead” in 15-20' 
[surely some immobilized 
only, see Exps 131-2] 
Ren. 
244 
CS 2 
200 c.c. atomized per cbm. in 
Amsterdam disinfection wag¬ 
gon. Nits in cotton plugged 
tubes twixt clothing 
3/10 of nits survived 24 hrs, 
nits killed in 48 hrs 
s. 
245 
800 c.c. per cbm. sprayed on 
clothes in metal box. (Men 
engaged suffered slight toxic 
effects. Odour soon vanishes. 
Method of Kais. Ges.-Amt.) 
Nits killed in 24 hrs 
S. 
246 
Formalin 
Evaporated by Fliigge lamp at 
40 x strength used for house 
disinfection 
10/25 of nits survived 24 hrs 
s. 
247 
? J 
I,ice on underclothes. No fur¬ 
ther particulars 
Lice survived 2 hrs 
M. 
248 
SO, (Clayton), 2-5 % 
Test lice and nits hung with 
effects in fumigation hut used 
by Captain Gair (17 lots of 
insects tested) 
Lice killed after 7 hrs ex¬ 
posure, 1 nit out of many 
survived and louse success¬ 
fully raised 
B. 2 
249 
Q .1 o/ 
?> 5 ? O -L /o 
ditto 
Lice killed after 7 hrs ex¬ 
posure, 2 nits survived but 
hatched tardily 
B. 2 
2. On Man. 
(a) Under conditions supposedly simulating the natural. 
Note regarding methods. Swellengrebel (1916, pp. 16-29), like Gross, 
Nocht, and others, found that tests conducted in vitro are liable to be 
fallacious. He therefore tested the effect of insecticides and repellants 
on his arm beneath a sleeve tightened at the wrist and near the axilla. 
Young lice were placed in a tube and the insecticide alongside so that 
