40i 
' and a coincident increase in the leucocytes, notably the phagocytes. 
‘At the eighteenth hour parasites were absent and could not be 
' found, even after blood centrifugalisation. Instances of 
phagocytosis were observed on three occasions.’ 
Thomas and Breinl tried the effect of hyperleucocytic agents 
without good effects, but remark: It is quite evident that the 
‘ leucocytes play a role in the decrease of parasites.’ 
We think that it is possible that on some occasions, at least, 
Thomas may have happened to give atoxyl at the time when the 
leucocytes were increasing and the parasites were diminishing, as 
we have shown to occur naturally. 
VI. THE HAEMOGLOBIN AND RED CELLS 
During the course of the disease, from February till the patients 
death in June, the haemoglobin percentage fell more or less steadily 
from 85 to 70 per cent. We could not detect any variation in the 
amount of haemoglobin corresponding to the parasitic cycle. 
The number of red cells was deficient (3,800,000 in March, 
2,800,000 in June). Their numbers were not estimated frequently. 
VII. THE EFFECTS OF TREATMENT BY VARIOUS DRUGS 
The crucial test of a curative treatment in this disease would 
naturally be the effect of the treatment on the numbers of parasites, 
especially in our case, where the numbers were estimated daily. 
In testing the value of various therapeutic agents, we have 
therefore taken the graph of the number of parasites as the indicator 
of the efficacy of that agent. We would like also to point out that 
in estimating the effect of treatment by this method, the blood must 
be examined every day, otherwise the effects recorded might be 
erroneous. If a drug be given at the height of a parasitic rise, and 
the blood examined next day or a few days later, the num er 
parasites would naturally be much less; to conclude from t is t 
the drug has caused this diminution might be quite erroneous 
is obvious that no conclusion should be drawn until the numbers 
have been estimated daily for several weeks. 
We think it may be possible that a drug such as atoxyl may by 
chance have been given, sometimes, just as the parasites 
/ 
