1907.) Experimental Treatment of Trypanosomiasis in Rats. 5 
inoculated rats, the antimony glycine was found to possess, in a less degree, the 
power of the antimony compounds described below; it reduced the number of 
trypanosomes, and caused their disappearance from the blood for a time, if 
they were not very numerous. 
But the combination was difficult to make, varied in strength, and its 
solution was very dilute, and its use was abandoned when it was found that 
the other antimony compounds, described below, were so much more 
‘effectual. 
. Potassium Antimonyl Tartrate. 
Potassium antimony] tartrate (tartar emetic), which is easily soluble, was 
then tried. In doses of 1 c.c. of a 1 per cent. solution it proved fatal within 
‘24 hours to four inoculated rats of weights varying from 190 to 225 grammes, 
but it was noticed that the trypanosomes had greatly diminished in number. 
It was also noticed that the rats appeared to be ill and faint for a short time 
after the injection: they were unsteady and sometimes rolled about. This 
was at the time attributed to the depressing effect of the potassium in the 
compound, and suggested the making and using of the substance described 
below, with which all of our experiments have so far been done. The question 
of the effect of this particular salt on the rats themselves will be mentioned 
later. Experiments are in progress for the purpose of comparing the actions 
of the potassium and sodium compounds: the latter would seem to possess 
some theoretical advantage, especially in treating larger animals, when the 
dose will have to be proportionally larger. 
Sodium Antimonyl Tartrate. 
Through ie kindness of Dr. R. H. Aders Plimmer, of University College, 
‘we have been able to obtain and use this compound, which is the sodium 
salt corresponding to potassium antimonyl tartrate. He has prepared a 
quantity of the pure substance for us, in crystalline form, and has written the 
appended Note* upon its chemistry. 
_ This substance in 1 per cent. solution is that which, of all the various 
bodies mentioned in these papers, including atoxyl, has the most marked 
and remarkable influence upon trypanosomes in the living body. Although 
our experiments with it are not many, nor of long duration, the results so far 
seemed sufficient to induce us to call the attention of other workers in this 
field to it. : : 
‘The injection of this compound causes no pain, nor does it produce any 
inflammation of the tissues; and the results of the injection are very striking. 
The oo disappear with great rapidity from the blood, and in the 
-* See Note at end of paper, p. 11. 
