674 FOURTH REPORT — 1834. 



The accuracy of Dr. Reid's statement as to the great diminu- 

 tion or apparent exhaustion of the irritability of the muscles 

 mider the influence of the galvanism, and the subsequent reco- 

 very of the power, notvi^ithstanding the division of all their 

 nerves, was satisfactorily established. It is to be remarked, 

 however, that in these experiments, as usual in such cases, the 

 limbs to which the galvanism was applied were kept moist by 

 the same saline solution with which the galvanic trough was 

 charged ; and Dr. Thomson has observed, that when they are 

 moistened with pure watei\, the diminution of the irritability 

 under the excitement by galvanism is much less obvious. 

 Hence he was led to suspect that the apparent loss of power in 

 the muscles under that process might depend, not on the cir- 

 cumstance of repeated excitement, but on a degree, however 

 slight, of injury to their texture by the action of the salt. This 

 inquiry he proposes to prosecute further ; but in the mean time 

 it is certain that by the usual process of galvanizing a living mus- 

 cle moistened by a saline solution, a very great diminution of its 

 irritability may be effected, Avhich may subsequently be regained, 

 notwithstanding the division of all its nerves ; and as the fact of 

 its recovery, not the cause of its diminution or exhaustion, is 

 the point on which the inference drawn from these experiments 

 rests, that inference may be held to be sufficiently justified. 



Notice of some Observations on the vital projjerties of Arteries 

 leading to inflamed parts. By Dr. Alison. 



These observations were made with the able assistance of 

 Mr. Dick, veterinary surgeon, on the arteries of the limbs of 

 several horses, condemned on account of injury and inflamma- 

 tion there. 



The immediate object of inquiry was, whether the tortuous 

 and strongly pulsating arteries leading to an inflamed part are 

 really endowed with a greater vital power of contraction than 

 sound arteries ; and the method taken to ascertain this was, 

 to make a comparative examination of the condition of these 

 arteries, and of the corresponding arteries in the opposite 

 sound limbs, immediately on the animals being killed (by blow- 

 ing air into their veins) ; and again after the lapse of 16 or 24 

 hours, when it is known that the tonic contraction, which takes 

 place at the time of death, and is the indication of the only 

 vital power which experiments authorzie us to ascribe to arteries, 

 has relaxed. 



The animals were killed, and the observations made, at dif- 

 ferent periods varying from twelve hours to twenty days after 



