29 



the following conclusions have been arrived at. The animal selected 

 for observation has been the dog, subsisting upon an animal diet, and 

 operated upon at a period of full digestion. 



" Division, on both sides of the neck, of the ascending branches of 

 the superior thoracic ganglion which run up towards the canal 

 formed by the foramina in the transverse processes of the vertebrae, 

 for the vertebral artery, occasions an intensely marked diabetes. The 

 urine has been found most strongly saccharine within even half an 

 hour after the operation. The diabetic condition is only of a temporary 

 character, passing off by the next day, and fatal pleurisy is always 

 induced. 



" Division of the ascending branches of the superior thoracic 

 ganglion on one side of the neck only, has occasioned merely the 

 presence of a trace of sugar in the urine in an hour and a half s time. 

 The same operation then performed on the other side has produced 

 in half an hour's time an intensely saccharine urine. 



" Carefully ligaturing the two vertebral and the two carotid arte- 

 ries does riot lead to saccharine urine ; but when the carotids have 

 been tied, and the tissue in connexion with the vertebrals before their 

 entrance into the canals is a little roughly treated, without however 

 dividing the larger sympathetic filament ascending from the superior 

 thoracic ganglion, the urine is rendered rapidly and strongly saccha- 

 rine. 



"Division of the sympathetic filaments that have entered the 

 canals does not alone produce diabetes ; but if the contents of 

 these canals be divided, and the carotid arteries at the same time 

 ligatured, saccharine urine is the result. 



" This result is produced when the contents of the osseous canals 

 are divided as high as the second cervical vertebra. It has also arisen 

 after destroying the structures in the neighbourhood of the vertebral 

 foramen on the posterior surface of the transverse process of the atlas, 

 but has not yet been noticed after a similar operation on the anterior 

 surface of the process. 



" Dividing the contents of the canals and the tissue in immediate 

 contact with the carotid vessels has not produced diabetes ; but when 

 the carotids have been afterwards tied, strongly saccharine urine has 

 resulted. 



" Of all the operations on the sympathetic of the dog that have yet 



