212 MR. COSTELLO ON THE TORSION OF ARTERIES. 
rysm of the carotids, for in the latter case there is great risk of 
the ligature giving rise to fusees of pus descending into the ca¬ 
vity of the thorax. The application of ligatures requires the aid 
of an assistant. The torsion may be effected by the operating 
surgeon alone, and, undoubtedly, on the field of battle, this is 
an incalculable advantage. It is also but fair to infer from what 
precedes, that torsion may be of the highest importance, in ope¬ 
rations which may be performed on the capillary side of an aneu¬ 
rysmal tumour. 
In compliance with a request made by the Society on the 
evening that the subject of the foregoing communication formed 
a topic of debate, Mr. Costello attended to perform the experi¬ 
ments of torsion before the members at the meeting of the 22d 
of February, when, after making a few prefatory observations on 
the cruelty of vivisection when the interests of science did not 
imperatively demand and fully justify it, he proceeded to expose 
the femoral artery of a terrier dog. The operation was performed 
with exactness and rapidity. The vessel being laid bare, and a 
probe passed under it, the members were invited to satisfy their 
minds that the vessel exposed was the femoral, by examining its 
size and pulsation; after which Mr. Costello placed two forceps 
on the artery in such a manner as to make the points opposed to 
each other leave* but a very short interval between them. He 
then divided the artery between the two forceps, and commenced 
twisting the upper portion of the artery, and, having counted five 
turns, he replaced it in the situation from which it had been 
drawn forth. For a short time there was no hemorrhage : he 
was now about to twist the capillary side of the artery, when the 
upper division gave out blood in a full stream ; he instantly stop¬ 
ped the hemorrhage with his finger, and requested Mr. Quain, 
who was assisting him, to twist the other extremity of the ves¬ 
sel, which was still held in the forceps. Mr. Quain made eight 
turns, and, having replaced the artery, not a drop of blood came 
forth. Mr. Costello now seized the upper end of the artery, and 
having twisted it seven times, replaced it. The wound was then 
examined by many of the members; there was not only no he¬ 
morrhage from either of the ends of the artery, but the wound 
itself seemed bloodless. The experiment was deemed to be so 
satisfactory, that the carotid was not exposed, as was at first in¬ 
tended, and the satisfaction of the Societv was testified by much 
applause. The observations which were afterwards made by 
members terminated in a general assent to the reasonings of Mr. 
Costello and the value of the process demonstrated. 
Lancet. 
