272 DADD'S VETERINARY MEDICINE AND SURGERY. 



stick is preferable for the piirpose of striking the fleam. There ii 

 a vibration between two hard bodies when they meet, which, in 

 this instance, is favorable to a quick and moderate puncture of the 

 vein. After the vein has been opened, mcderate pressure with the 

 edge of the can which catches the blood is sufficient tc keep up 

 the flow. It may c^so be encouraged by putting a finger within 

 the horse's moutli. The requisite quantity of blood being drawn, 

 remove the can. The remaining process of securing the ♦^essel 

 is of equal importance. The sides of the orifice are first to be 

 brought in opposition, without pinching them, and without draw- 

 ing them from the vein. The same cautions should also be ob- 

 served when the pin is introduced. Let it be small, with an 

 irregular point, and, when inserted, wrap around it a few hairs 

 or a little tow. 



Common, however, as this operation is, and qualified as every 

 one thinks himself to perform it, yet there are very serious acci-. 

 dents which do arise occasionally. It has occuri ed that the carotid 

 artery has become penetrated. When the puncture has been made 

 through the vein, the accident is known immediately by the forci- 

 ble and pulsatory gush of florid arterial and dark venous blood 

 together. In one instance of this kind, whioli occurred to a French 

 practitioner, he immediately thrust hi^ finger into the opening 

 through the vein, and thus plugged up the artery, intending to 

 wait for assistance. In this state he remainpd, we believe, an 

 hour or more, when, removing his finger, to his surprise, he found 

 the hemorrhage liad ceased, and did not again return. In another 

 case, where an English practitioner accidentally opened the carotid, 

 he placed a compress on the orifice, and had relays of men to hold 

 it there for forty-eight hours, when it was found the bleeding had 

 jtopped. 



The aimission of air is also another serious accident that now 

 and then attends bleedmg. It sometimes happens from the sudden 

 removal of the fingers or blood-can, or whatever was used to dis- 

 tend the vessel by obstructing the return of the blood. This, being 

 suddenly taken away, allows the escape of the blood toward the 

 heart, and occasions a momentary vacuum, the air being heard to 

 rush with a gurgling noise into the vein through the orifice; it 

 then mixes with the blood, and occasions, in some instances, almost 

 immediate death. The animal begins to tremble ; he next staggers, 

 And finally falls in a state* of convulsion. If the quantity of ai» 



