64 ON THE ANTISEPTIC SYSTEM 



however, the thread were steeped in some hquid calculated to destroy the life 

 of the germs in its interstices, and the wound by which it was introduced were 

 dressed antiseptically, the ends of the Hgature being cut short, it might be left 

 with confidence that its presence would not interfere with primary union, or 

 occasion any disorder in the surrounding parts. [The traction exercised on the 

 external coat by the noose of the ligature is no doubt a temporary cause 

 of mechanical irritation, but this does not appear to have any considerable 

 influence.] Before applying these principles upon the human subject, I thought 

 it right to test them on one of the lower animals. 



Ligature of the Carotid Artery in the Horse, on the Antiseptic System. — On 

 the I2th of December last, I tied the left carotid of a horse about the middle 

 of the neck, using fine but strong ' purse-silk', unwaxed, but steeped for some 

 time in a saturated watery solution of carbolic acid. [The product of the action 

 of carbolic acid upon blood serves the purpose of wax in preventing the first 

 half of the knot from slipping during the tying of the second half.] The ligature 

 having been tightly tied, so as to rupture the internal and middle coats, its 

 ends were cut short, and the wound was freely treated with carbolic acid dissolved 

 in forty parts of water. Seven stitches of the coarse soft wire used by veterinary 

 surgeons for the purpose were introduced into the long wound, the most depen- 

 dent part being left free for the escape of discharge. The hair around the 

 wound was well rubbed with a solution of carbolic acid in four parts of olive oil, 

 and cloths saturated with the same antiseptic oil were applied overlapping the 

 surrounding skin freely, and retained in position by means which I need not de- 

 scribe ; and similar oil was poured daily upon the cloths for the first six days. Ten 

 days after the operation I removed the dressings, and found the wound perfectly 

 united throughout, except at the part purposely left open, which was covered 

 with a sort of cheesy material, and as each stitch was removed there was absence 

 of even serous exudation. The wound was now left exposed, and in three days 

 more the lower part had healed by scabbing, no suppuration having occurred from 

 first to last. At the same time, there was none of the swelling and induration 

 that usually attend the application of a ligature to a vessel in the horse's neck, 

 and the animal showed no signs of uneasiness when the part was freely handled. 



Five weeks and four days after the tying of the artery, the creature, though 

 it had improved greatly in condition under its superior diet in the veterinary 

 establishment, died, as the groom believed, of exhaustion from struggling in- 

 effectually to rise from the recumbent posture. I had thus an opportunity of 

 inspecting the parts concerned in the operation, some of which are now before 

 you. In the first place, here is a portion of the skin containing the scar ; and 

 you will observe that it is a perfectly sound linear cicatrix, barely traceable 



