On Pithing Cattle. 75 



beating exceedingly slow and weak. We suppose he died 

 aboat six in the morning, having survived the operation 

 sixteen hours. This experiment I made from the suggestion 

 of Mr. Hunter, with a view to obviate the objections raised 

 against the reasoning drawn from the three first experi- 

 ments. It was urged, that though by these experiments I 

 had deprived the thoracic and abdominal viscera of their 

 ordinary connexion with the brain, yet, as the intercostals 

 communicated with all the spinal nerves, some influence 

 might be derived from the brain in this way. This expe- 

 riment i-emovcd also the spinal nerves, and consequently 

 this objection. 



" As I found by the two last experiments that dividin<T 

 the spinal marrow in the lower part of the neck did not 

 immediately kill, although instant death was universally 

 knowii to be the consequence of dividing it in the upper 

 part of the neck, I expressed my surprise to Mr. Hunter, 

 that the spinal marrow should, according to modern theorv, 

 be so irritable in the one place, and so much less so m tlic 

 other. 



*' He told me, that froin the time he first observed that 

 men who had the spinal marrow destroyed in the lower part 

 of the neck lived some days after it, he had established an 

 opinion, that anhnals who had the spinal marrow wounded 

 in the upper part of the neck did not die froin the mere 

 wound, but that in dividing it so high we destroyed all the 

 nerves of the muscles of respiration, and reduced the animal 

 to the state of one hanged ; whereas, in dividing it lower, 

 we still left the phrenic nerves, and allowed the animal 

 to breathe by his diaphragm. If this opinion be well- 

 founded, though dividing the spinal marrow in the lower 

 part of the neck does not kill instaiulv, whil.st the phrenic 

 nerves are untouched, yet, if I divide the phrenic nerves 

 first, and then divide the spinal marrow in the lower part of 

 the neck, tlie consequence, I said, will be the same as if I 

 had divided it in the upper part. 



" J'.rpcrhnent VHI. — By detaching the scapula^, of adoo; 

 fr^m the spine and p.".rtly from the ribs, J got at the axillary 

 plexus of nerves on both sides from behind. 1 separated 

 the arteries and veins from the nerves, and passed a ligature 

 under the jjerve^ close to the spine. I thought I could 

 discern the phrenic nerves, and instantlv divided two con- 

 siderable nerves going off from each plexus. The action of 

 the diaphragm seemed to cease, and the alidominal muscles 

 1)e.-ame fixed, as if they had been arrested in expiration, 

 the belly appearing contraettd. His respirations were now 



about 



