VOL. LXXXV.J PHILOSOPHICAL TRANSACTIONS. 513 



forward towards the middle of the spine, perforates the diaphragm, and then 

 terminates in the simihmar ganglion of the intercostals. These trunks are dis- 

 tinguished by the name of the anterior intercostals. The original trunks con- 

 tinue their course by the sides of the lumbar vertebrae; after which ihey run 

 before the os sacrum, and, approaching nearer each other as they descend, ter- 

 minate before the os coccygis, in the ganglion coccygeum impar of Walther. 

 Their branches all go to the heart, abdominal viscera, testicles in men, and 

 ovaria and uterus in women. The trunks of these nerves are largest in the 

 neck. In the human species, the 2 nerves of each side are distinct ; but in 

 those quadrupeds which I have examined, they are so closely connected through 

 the whole length of the neck, as to make apparently but 1 nerve. The inter- 

 costal is the smaller nerve, and adheres so closely to the other, as to be with 

 difficulty separated from it. They seem to me likewise larger in the dog, com- 

 pared with his bulk, than in the human subject. The neck was the place in 

 which I chose to divide these nerves; it was there they could be got at with least 

 danger, a circumstance which, by making an experiment more simple, makes it 

 consequently more to be relied on; and, in order to put the animal to as little 

 pain as possible, and make the operations short, I chose to divide both nerves at 

 once, rather than take up time in separating them, and dividing them singly; so 

 that, instead of 4 operations on each artmial, I confined myself to 1. Instead of 

 mentioning the names of the gentlemen present at each experiment, I shall 

 observe once for all, that 2 or more of the following gentlemen were present at 

 each experiment, except experiment 7, which I performed, assisted by Mr. 

 Hunter's servant only: — Messrs. Barforth, Bayley, Davidson, Hartley, Haw- 

 kins, Home, Kuhn, Noble, Parry, Martin, Sheldon, Wheatly; besides others, 

 who came in occasionally, during the time of the experiments, or who afterwards 

 saw the animals, while the described symptoms were taking place. 



Exper. 1. Jan. 24th, 1776, I divided, Jn a dog, ] nerve of the par vagum, 

 with the intercostal, on the right side. The symptoms, consequent to the ope- 

 ration, were heaviness, and slight inflammation of the right eye; breathing 

 with a kind of struggle, as if something stuck in his throat, which he wanted 

 to get up; sullenness, and a disposition to keep quiet: the pulse did not seem 

 much affected, nor had he lost his voice in the least. The unfavourable symp- 

 toms did not continue above a day or two; and on the 8th day he was in very 

 high spirits, and seemed perfectly to have recovered. 



Exper. 2. Feb. 3d, I cut out a portion of the 2 nerves of the opposite side, 

 in the same dog; the piece might be about 1 inch long. His eyes became in- 

 stantly red and heavy; his breathing was more difficult than in the former ex- 

 periment, he was sick, and vomited frequently ; the saliva was increased in quan- 

 tity, and flowed ropy from his mouth; his pulsfe in the groin was about l6o in a 



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