503 
We first experimented with ■> vacei ii e obtained at the height o 
the rise. Here it was noted that after subcutaneous injection a rise 
in the number of trypanosomes took place. The fact was rat "° e 
bv D Thomson, while conducting similar work on the human case 
of sleep,ng s.ckncss. This observer asserts that an injection of a 
so-called vaccine which was simply tats’ blood, sterilised and mixed 
with normal saline-rich in the dead bodies of trypanosoma, 
stimulated the trypanosomes in the peripheral oo o ,e 
to divide; and the explanation seems to be based on the hype*he 
of Dr. H. C. Ross, who holds that extracts of dead animal tissues 
stimulate cell division . , , _ , . • „ 
In our experiments with rats infected witi • not » 
without except.<md that when the blood of 
trypanosomes was injected subcutaneously, a rise ° was 
occurred during the next twenty-four hours. OS e was 
sometimes very sudden and exceedingly high, and 
large and strong, the rise was (several tunes; so gre treatment 
the death of the animal. Plus is exactly in me wi i ^ ^wn 
of disease with true bacterial vaccines, and here i excessive 
that if we treat say a mastitis with vaccine an g> ^ & small 
dose, we aggravate the condition. On t e o er ’ next 
dose was given to an infected rat. we got during t 
twenty-four hours a rise, but not sufficient to & ^ 
rise may well be represented as the nega ivc be 
occurs usually in forty-eight to seventy-two hours, which > 
considered as the positive phase. . . t i e., it must 
We conclude, therefore, that the dose - '.^“ “ow an interval 
not be too large, and secondly, we must a least allow 
of one day before a second dose is adminis e ^ in f ecte d with 
In our first experiments use another rat, which 
T. rhodesiense, and vaccine was prepare height of a crest, 
was killed when the trypanosomes v-ere a relatively poor in 
We thus used a blood rich in trypanosomes, treated, 
anti-bodies. Three rats were kept as controls andjhree^^ ^ ^ 
Two of those treated quickly succu without blowing an 
the fact that we gave two dos Wc gave no time for a 
interval of at least twenty-four hour^ --- --- 
•Brit. Med. Joorn.. June tl, » 9 ‘°* 
