249 



solution or of venous hluod IVoni a noi-nuil dog or of blood from 

 the pancreatic duodenal vein. The amount of glycogen was estimated 

 before and after the irrigation. 



To this conduct of the experiment the following objections may 

 be raised : 



1. One dog is more susceptible to the narcotic than another, and 

 moreover reacts in a different way (to mention an essential point, 

 there is a difference in the duration and in the intensity of the stage 

 of excitation). 



2. A laparotomy is performed and part of the liver is extirpated 

 durante vita, to which stimulant acts various dogs are apt to respond 

 in different ways. 



3. Some loss of blood is inevitable. 



We should bear in mind, however, that every experiment upon 

 a living organism must involve errors, but also that if the experi- 

 ment is performed upon a large number of animals these errors 

 may probably neutralise each other in part or altogether. 



Method: Dogs of from 4 to 22 KGs. were narcotized with chloro- 

 form ; the abdomen was opened and a portion of the liver was 

 removed. The following precautions were taken; the operation was 

 always performed in a very warm room (21°— 26° C) to minimize 

 the fall of temperature. The narcosis was as profound and as restful 

 as possible. The portions of liver removed varied between 20 and 

 40 grs. ; they were cut off by means of scissors that were rather 

 blunt and had been warmed beforehand ; there was no fear of 

 parenchymatous bleeding and only some large veins had to be 

 ligated. The abdomen was left open only for a \Q,Yy short space 

 (except of course in the two cases of injection per pancreatic vein) 

 and even then the laparotomy-wound was covered throughout the 

 whole experiment with a warm tampon, soaked with physiological 

 saltsolution. Subsequently fluids were injected per jugular vein for 

 one hour and a half in most of the experiments. Irrigation was 

 performed from a burette on stand, so that the velocity of the in- 

 flowing liquid could be regulated by means of a tap. 



After one hour and a half another piece of liver of approximately 

 equal weight was cut off as fast as possible. 



Finally a determination was made of the amount of glj^cogen of 

 both pieces of liver. In order to ensure a proper amount of glycogen 

 the animals had been given about eight hours before the operation 

 a diet consisting of 100 grs. of cake. Owing to outward circum- 



