of a partial Obstruction of the Circulation. 481 



One of the remedies usually employed is topical bleeding, 

 which, by relieving the vessels of their contents, gives them 

 an opportunity to contract ; and by the reaction, to return 

 to their natural state. In like manner blisters act by reliev- 

 ing the distention of blood, and stimulating the weak vessels 

 to action, but a much more simple and certain remedy, in 

 these cases, is the application of a ligature, so as to retard 

 or stop the circulation in the limb in which the morbid 

 circulation exists, and thus introduce a new action in the 

 part. This may likewise be effected in some internal diseases 

 by stopping the circulation in one or two limbs, which throws 

 more blood into the trunk, and thus removes the topical 

 congestion. 



The following experiment was made upon a strong, healthy, 

 young man, to ascertain the effect of obstructing the circula- 

 tion in health ; when the temperature of the air was 85°, the 

 pulse at the wrist 80°, and the temperature of the body 98°. 

 The tourniquets were applied to the thigh and to the opposite 

 arm ; and in a few minutes the limbs became cold and 

 numb, but soft and flexible. The temperature of the hand 

 on the side to which the ligature was applied fell to 93°, and 

 in the axilla beyond the ligature to 97°. The other parts of the 

 body after the ligature was applied appeared much warmer 

 than before, and a perspiration covered the skin ; pulse 88°, 

 while the temperature of the axilla was 102°. In five minutes 

 after the ligature had been applied to the limb, the heat of the 

 surface and pulse of the remainder of the body increased in 

 velocity by twenty beats in a minute, so as sometimes to 

 cause a flushing of the face, anxiety, and frequent respirations. 

 In six minutes the obstruction of the circulation induced a 

 tendency to syncope as in a plethoric person. Immediately 

 on the removal of the obstruction, these symptoms disappear- 

 ed, and the pulse fell below its natural standard : and in an 

 hour after, it is often ten beats slower than it was previous to 

 the application. Thus the effect of obstructing the circula- 



