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(6) Strychnine arseniate followed, by quinine arseniate 
Curative .— Four rats infected with T. brucei each received 2 5 c.cm. of a -06 
solution of strychnine arseniate and 2-5c.cn!. of a -i per cent, solution of quinine 
arseniate, as in the preceding experiment. The drugs were given separately, at 
twelve hour intervals, each in three doses on three successive days. The animals 
died on the fourth day, that is two days after the appearance of parasites in the 
blood. A few degenerate trypanosomes were noticed on the second day. 
From these experiments we conclude that 
Strychnine has probably no harmful effect on Trypanosoma 
brucei or T. gambiense. 
III. ATOXYL, FOLLOWED BY MERCURY 
Our work has been directed by the idea 5 that perhaps the 
recurrences in cases of trypanosome infection, after treatment by 
atoxyl, might be due to some resistant stage of the parasite which 
survived the first treatment by atoxyl and later gave rise to recur¬ 
rences of trypanosomes more or less refractory to atoxyl treatment. 
It was thought that these hypothetical resistant forms might be 
influenced by some other drug. A series of experiments on the 
treatment of animals infected by trypanosomes was therefore 
commenced in which atoxyl was followed by some other drug. Lp 
to the present the best results have been obtained by the use of atoxyl 
followed by mercury. We present the results of this treatment on 
rats infected with Trypanosoma brucei. 
[a) Atoxyl followed by the bichloride of mercury 
The same solution of atoxyl was used as in the preceding experi¬ 
ments. T he mercury was given subcutaneously in a O' 1 per cent, 
solution (Liquor Hydrargyri perchloridi, B.P.). 1 he mercury was 
never given until parasites could no longer be found by the examina¬ 
tion of coverslip preparations. That they were probably usually 
absent from the blood in an infective form is shown by the fact that 
n °ne of four animals inoculated, as controls, with blood taken from 
;' uese experimental animals after their treatment by atoxyl have ever 
income infected. 
Experiment (no).— Four rats received subcutaneously 0-5 c.cm. of a 5 P er 
J Solulion of atoxyl (the same strength of solution is used in the same way 
«s otherwise stated, in all the following experiments) on the third day of infection, 
• e >ghth day after inoculation, with trypanosomes. On the four following days 
Cl , Cm of 1116 °'i per cent, solution of perchloride of mercury was given su 
"laneousiy (the same solution was employed in the following experiments). 
