PORSE MANAGEMENT, ETC. 407 



of operatiou most Hkely to be successful, I shall now proceed tc 

 state the result of foar cases in which I have operated, and which, 

 I think, I may look upon as having been followed with entire 

 success. In th^ee of the cases the patients had been bled a short 

 time previous to ray having seen them, and were so much Tveak- 

 fned that they could scarcely walk. In the fourth case, a drastic 

 purgative had been administered, causing superpurgatiou and greiit 

 prostration of strength. In each of the four cases, the condition 

 of the patient was so similar that the description I have alieadf 

 given may answer for all. Having selected a healthy young horse 

 from wliicli to obtain the blood to be transferred, I opened thfl 

 jugular vein in the patient and in the healthy subject; and hav- 

 ing inserted the tube, as before described^ into the vein of the 

 healthy horse. I placed the India-rubber tube in the tin trough 

 containing hot water, to maintain the right temperature, and the 

 other curved tube into the descending portion of the vein in the 

 patient. As soon as the current from the healthy horse had com- 

 pletely expelled all atmospheric air, the instrument being thus 

 arranged, the blood flowed freely from the vein of one horse into 

 that of the other in an unbroken current. The average quantity 

 of blood transferred in each of these cases was about three quarts. 

 J observed no particular symptoms to follow from the transfusion, 

 until two quarts or more had passed from the healthy to the disk 

 eased subject ; but as soon as about that quantity had flowed, ther* 

 appeared to be produced an amount of stimulation, indicated by an . 

 increased action of the heart ; at the same time the pujjils began to 

 dilate, and the countenance evinced an anxious expression. My 

 former experiments led me to watch with great care the progress- 

 ive dilatation of tlie pupil, and I deemed it expedient, in each case, 

 when this symptom was well developed, to compress the tube so 

 us to diminish the current, and allow the transfusion to proceed 

 more gradually and slowly. Occasionally I almost compKtely 

 interrupted the current until the subsidence of this symptom, and 

 I found that when about three quarts had been transfused, any 

 additional quantity was followed by unpleasant symptoms, which 

 indicated the necessity of stop])ing the operation. On removuig 

 the tube and closing the vein, all symptoms of irritation grachiully 

 subsided, and the pulse, from being rapid and irritable, became 

 slower, stronger, and fuller, gradually approaching the healthy 

 tandard. 



