74 ON SPONTANEOUS GANGRENE FROM ARTERITIS AND 
air, by means of a condensing syringe, into the tissues of the lower part of the 
limb. The struggling of the animal, however, caused repeated displacement 
of the tourniquet, which I did not succeed in retaining in position for longer 
than an hour at a time. But, though the experiment was so far a failure, it 
yielded fruit in an unexpected manner. Having amputated the limb and pre- 
served it, though with little expectation of learning anything from it, I was 
surprised to find, on examining it six hours later, that, although the cellular tissue 
about the vessels was still fully distended with air, the blood within them was 
perfectly fluid, and coagulated in about two and a half minutes, when shed 
into a saucer. Still greater was my surprise on finding next day, sixteen hours 
after the amputation, that the blood was still fluid in the vessels ; and though 
it took longer to coagulate when let out from them, viz. five minutes, did so as 
fully as before. The muscular irritability, as tested by a powerful galvanic 
battery, had been found, on the previous evening, to be entirely lost. I next 
obtained four other feet, with the veins turgid with blood, by applying bandages 
firmly to the limbs below the joints where the butcher removes them, and 
amputating above the constricting band, after the sheep had been killed in 
the usual manner, by the knife. I examined veins in these limbs, day after day, 
till all the vessels were exhausted, and found at the end of the sixth day after 
their severance from all connexion with the vascular and nervous centres, that 
the blood from a deep vein was still perfectly fluid, and coagulated when shed, 
though the time occupied by the process was now half an hour,—the length of 
the period having gradually increased, from day to day, since the time of the 
amputation. The feet, in the meantime, continued perfectly sweet, the coldness 
of the weather at the time being very favourable for the experiments. Some 
blood from a subcutaneous vein of the same foot, where decomposition might 
be expected to occur somewhat earlier, contained, at the same period (the end 
of the sixth day), some minute portions of coagulum. The fluid part of this 
blood remained liquid for an hour, but then coagulated well. Hence it was 
evident that so long as the tissues retained their freshness, the blood within 
the vessels was kept in a state of fluidity by some agency utterly inexplicable 
by the ammonia theory. I also found that the same thing occurs in the cat. 
In one such animal, killed under chloroform, by a knife passed into the great 
vessels of the neck, the blood in the veins of the extremities remained perfectly 
fluid after forty-eight hours, and coagulated when shed. In another cat, killed 
by asphyxia, the same was the case as regards the posterior extremities ; but 
the veins of the fore legs contained particles of coagulum, like the subcutaneous 
vessel of the sheep’s foot. This difference I am inclined to attribute to the 
fact that the animal made violent and protracted exertion with the fore legs 
