208 
Theory and Practice of Dipping 
At no time could any effect on the ticks (Boophilus decoloratus) be 
observed. The post-mortem examination showed the usual symptoms 
of acute arsenical poisoning. 
It is evident therefore that the internal administration of arsenic 
is useless, whether in large or small quantities. 
Appendix IV. 
The Effect on Ticks of Arsenic administered subcutaneously. 
The object of these experiments was to determine the effect of 
local subcutaneous injections of arsenical solutions on ticks attached to 
the host. It was anticipated that by such means it might be possible 
to ensure the presence of a sufficient quantity of arsenic in the circu¬ 
lating blood to destroy the ticks which fed upon the treated animal. 
The subjoined protocols show that such injections are purely local in 
their action, and that with the exception of those ticks which are 
attached immediately round the site of the needle-puncture no effect 
is to be observed. Unfortunately the general symptoms produced in 
the host made it impossible to continue these experiments, and, for the 
same reason, no certain conclusion can be drawn from the results 
obtained. 
Beast No. 0102. 
Date 
1909 Temperature 
Effect on ticks 
Remarks 
March 9th 
0-25 gm. of As 2 0 3 , as sodium 
arsenite, dissolved in 3 c.c. of 
water injected subcutaneously 
on right shoulder; a similar 
dose injected on the escutcheon 
Parts round sites of injection 
swollen and inflamed 
Skin over swollen areas cracked 
and raw surfaces infested with 
maggots. Wounds cleaned and 
disinfected with carbolic acid 
All living ticks killed by applica¬ 
tion of oil; beast cleaned and 
disinfected 
Wounds healed and beast quite 
14th 105-8° F. 
17th 104 0 „ 
All ticks dead over an 
area of some 6 ins. x 
3 ins., surrounding the 
site of the needle-punc¬ 
ture. Some adults 
had gorged. Else¬ 
where, ticks unaffected 
Ticks on body generally, 
still unaffected 
26th 105-2 
April 7th 
