1910.] Hxpervmental Treatment of Trypanosomasis. 147 
follow. Large doses are best borne when injected into a peripheral vein 
in one of the legs, and one injection of 1 gramme will keep the blood 
free from trypanosomes for from 2 to 3 weeks. If the injection be made 
into the jugular vein considerable depression, and even faintness, may be 
induced. The use of a peripheral vein involves throwing the horse, which 
is risky if repeated doses have to be given. We have not yet ascertained the 
maximum dose. All the horses died with nervous symptoms, and although 
life has been prolonged (in one case to 121 days) none of them has shown 
satisfactory results. We have persisted in our experiments with metallic 
antimony because we hoped that, as it is taken up by the leucocytes, it might 
possibly be carried by them to, and be deposited in, parts not accessible 
otherwise; also, because we know that in syphilis the protozoon causing 
the disease is killed by the injection of metallic mercury We know 
also that syphilis requires a continued treatment, and it may be that in 
trypanosomiasis a continued treatment also is necessary. The effects produced 
by metallic antimony are so striking that we are emboldened to think that if 
the methods could be improved a much better effect would be obtained. 
The following Table summarises the experiments upon horses. 
| No. No. | Recur- 
Beate) Material and quantity given. EO A Remarks. 
(f Intramuscular— ;) ( 
20 per cent. suspension of 
| ; od ant. tart. 2 Abas | | a Aa Pe een tal for 17 days 
= medium. Doses from 1 to | + — 4 prone: death ied on 44th day 
) 
Da a allaeice with nervous symptoms and 
| pas a ie | | thoracic edema. Spleen normal. 
1 5 c.c. 5 per cent. ant. in 
L Lambkin’s medium 5 L 
Intravenous— | 
2 8 Ant. in salt solution. Doses 2 No trypanosomes seen for 19 days 
from 0°5 gr. to 1°25 er., before death. Died on 52nd day 
altogether 5:5 gr. with nervous symptoms. 
3 8 Ant. in salt solution. Doses 3 No trypanosomes seen for 20 days 
from 0'1 gr. to 2 gr., alto- before death. Died on 121st day 
gether 9°75 er. ' with nervous symptoms. 
4, 6 Ant. in salt solution. Doses| — __ | No trypanosomes seen after first dose. 
from O'1 gr. to 2 gr., alto- Died on 56th day with nervous 
gether 4°5 gr, symptoms. Had persistent thoracic 
oedema. 
| 
With the exception of No. 1, these horses were old and worn-out. 
It will be noticed that none of these horses had trypanosomes in the blood 
for some time before death; No. 3 appeared to be quite well up to the 
90th day, and No. 4 up to the 40th day, and both could apparently have 
worked up to these times. In all cases death was preceded by a very sudden 
ageravation of symptoms referable to the nervous system. 
