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DELAFOND'S EXPERIMENTS.
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although it had been closely fitted to the inside quarter, according to rule. It was not so firm on the hoof; the rivets were not so solid, or so well incrusted in the wall. With the other foot, shod on the hot method, nothing like this was observed; after, as before the experiment, the solidity of the shoeing was excellent. It was this test that led M. Reynal to believe that the caloric which impregnates the horn disposes it favourably for the reception of the shoe; that it destroys its absorbent, spongy, hygrometrical properties, and renders it insensible to external influences.[1]

With regard to the risk of injury from burning the sensitive parts enclosed within the hoof, the opponents of hot fitting, the majority of whom really knew little, if anything, of the matter practically, and either forgot or were unaware of the fact that horn is a slow conductor of heat, might have been converted by the experiments of Professor Delafond. He showed in a most conclusive manner, that a very long-continued application of the hot shoe was required to affect the vascular parts of the foot. Applying a small thermometer to the inner surface of the sole, and bringing a hot shoe in contact with the ground aspect of the foot, he found it required three minutes burning to produce any effect on the thermometer. Reynal also experimented to test this fact, and the result was, that the thermometer inside the hoof did not mark any change until after the sole had been roasted by a hot iron for a period three times longer than that needed for a farrier to fit his shoe. And M. Barthélemy has watched

  1. Vatel. Rapport sur la Ferrure à Froid. Soc. Centrale Vétérinaire, 1846.