Results of the Experimental Treatment of Trypanosomiasis. 355 



Most of the above rats died from cold ; none of them died from the 

 disease, and no trypanosoraes were found in their blood or organs, and 

 inoculations made therefrom were entirely negative. 



B. — Further Experiments. 



Rats treated with Lithium Antimonyl Tartrate, 1 per cent. 



A further series of experiments has been carried out with this substance 

 on a large number of rats, giving four doses of 4 to 5 minims (according to 

 weight) of a 1 per cent, solution subcutaneously, a dose being given every 

 other day. Practically by this method every rat can be cured. They have 

 lived for varying periods, up to 249 days, and in no case have trypanosomes 

 been found after death in the blood or in the organs. No rat has died of 

 the disease, and in no case thus treated has there been a recurrence. The 

 results have therefore been more constant than those attained with sodium 

 or potassium antimonyl tartrates. The treatment was begun on the third or 

 fourth day after inoculation ; it will be seen below that when it is left until 

 the number of trypanosomes in the peripheral blood is very great, although 

 they may be driven out of the blood, it does not cure : so that the time at 

 which treatment is commenced is of considerable importance. 



It has also been given intravenously in rabbits, but with far less effect 

 than when given subcutaneously. The elimination in this case is very rapid, 

 to which fact we attribute its comparatively feeble action. 



Hats treated with Lithium Antimonyl Tartrate on the Fifth or Sixth Day of 



the Disease. 



The blood at this period of the disease is swarming with trypanosomes, 

 and experiments were made in order to see what effect this salt of antimony 

 would have upon the disease at this period. If one dose of 5 minims 

 of a 1 per cent, solution be given the rats die on the seventh day, so that 

 little or no effect is produced. If two such doses be given, one on the fifth 

 and one on the sixth day, the average time of death in 10 rats was 19| days, 

 and living trypanosomes were found in the blood at death. When four doses 

 were given, one on each day from the fifth to the eighth, the time in three 

 rats was lengthened to 81 to 86 days : in one of these even living trypano- 

 somes were found in the blood after death. By comparing these results with 

 those mentioned in the former section it will be seen that the time at which 

 the administration of the drug is begun is of importance, as well as the 

 number of doses. The animals stand the best chance of cure when no 

 recurrences take place, and this is best ensured by the method described in 

 the previous section. 



VOL. LXXXI. — B. 2 D 



