510 
Combating Lousiness 
the lice to feed upon him during the period that the insects were 
exposed to the insecticide. This method permitted of no discrimination 
between contact and vapour action, but certainly allowed the insecticide 
to exert its maximum effect. 
* The protocols of Mr Bacot are dated as foEows: Nos. 286-95 (20. m. 17); 296-7 
(13. rv. 17); 298-300 (30. XI. 17); 301-3 (10. xn. 17); 304-6 (8. i. 18); 307-10(28. 
i. 18); 311-13 (16. xn. 16); 314-19 (undated); 320-1 (31. I. 17); 322-4 (6. m. 17); 
325-6 (10. m. 17); 327-8 (13. m. 17); 329-36 (14. xi. 16); 337-8 (30. xi. 17). 
Ref. 
No. 
Insecticide tested 
(vapour and contact) 
Results 
Time when flannel treated before lice put on it 
At once 
4—5 hrs exposure 
20—22 hrs 
4—5 hrs exposure 
298 
Oxford powder 
O 12/12 alive 
O 12/12 alive 
299 
Naphthaline, crude, and Oxford 
O H/11 
O 11/11 „ 
powder, 1 : 4 
300 
Naphthaline, crude 
+ 12/12 dead 
± 4/12 dead 
301 
Naphthaline and Oxford powder, 
+ 12/12 „ 
O 13/13 alive 
1:1 
302 
Ditto, 3 : 7 
+ 12/12 „ 
-b 6/12 dead 
303 
Ditto, 1 : 9 
+ 12/12 „ 
± 7/14 „ 
Ref. 
Insecticide tested 
Results 
Time when flannel treated before lice put on it 
No. 
(vapour and contact) 
1 hr 
4 hrs exposure 
20 hrs 
4 hrs exposure 
72 hrs 
6 hrs exposure 
304 
Hexachlorethane, 2 pts 
Vaseline, | pt 
Soft soap, | pt 
± 14/20 dead 
rest feeble 
± 2/21 dead 
rest active 
O 19/20 alive 
305 
Veratrine, | % in vaseline 
± 12/19 dead 
rest feeble 
± 9/19 dead 
rest feeble 
20/20 feeble 
306 
Naphthaline, crude, 10 pts 
Vaseline, 1 pt 
Soft soap, 1 pt 
+ 20/20 dead 
± 18/20 dead 
rest feeble 
O 22/23 alive 
Results 
Time when flannel treated before lice put on it 
No. 
(vapour and contact) 
1 hr 
20—24 hrs 
44—48 hrs 
68—72 hrs 
94 hrs 
Exposm-e 
4-| hrs 
9J hrs 
9 hrs 
6 hrs 
307* 
Harrison’s pomade 
23/37 feeble 
8/20 feeble 
14/22 feeble 
15/15 feeble 
— 
* Personal communication from Mr Bacot regarding experiments 307-310. 
