452 EXCRETION. 



Quantity of blood. Cholesterine. Cholesterine per 



grains. grains. 1,000 pts. 



Carotid 179-462 0'139 0-774 



Internal jugular 134*780 0-108 0'801 



Femoral vein 133-886 0-108 0'806 



Percentage of increase in the blood from the jugular over the arterial blood 3 -4 88 



Percentage of increase in the blood from the femoral vein over the arterial blood 4-134 



This experiment shows an increase in the quantity of cholesterine in the blood in its 

 passage through the brain, and an increase, even a little greater, in the blood passing 

 through the vessels of the posterior extremity. To facilitate the operation, however, 

 the animal was brought completely under the influence of ether, which, from its action 

 upon the brain, would not improbably produce some temporary disturbance in the nutri- 

 tion of that organ, and consequently might interfere with the experiment. For the pur- 

 pose of avoiding this difficulty, we performed the following experiments without adminis- 

 tering an anesthetic : 



Experiment III. A small, young dog was secured to the operating-table, and the inter- 

 nal jugular and carotid were exposed upon the right side. Blood was taken, first from the 

 jugular, and afterward from the carotid. The femoral vein upon the same side was then 

 exposed, and a specimen of blood was taken from that vessel. The animal was very 

 quiet under the operation, although no anesthetic was used, so that the blood was drawn 

 without any difficulty and without the slightest admixture. 



The three specimens were analyzed for cholesterine, with the following results : 



Quantity of blood. Cholesterine. Cholesterine per 



grains. grains. 1,000 pts. 



Carotid 143-625 0'679 0'967 



Internal jugular 29'956 0*046 1-545 



Femoral vein 45'035 0'046 1-028 



Percentage of increase in the blood from the jugular over the arterial blood 59'772 



Percentage of increase in the blood from the femoral vein over the arterial blood 6*308 



Experiment IV. A large and powerful dog was secured to the operating-table, and 

 the carotid and internal jugular were exposed. Specimens of blood were taken from these 

 vessels, first from the jugular, and were carefully weighed and analyzed for cholesterine 

 in the usual way. The following results were obtained : 



Quantity of blood. Cholesterine. Cholesterine per 



grains. grains. 1,000 pts. 



Carotid \ 140-847 0-108 0'768 



Internal jugular 97-811 0'092 0'947 



Percentage of increase in the blood passing through the brain 23*307 



Experiment III. shows a very considerable increase in the quantity of cholesterine in 

 the blood passing through the brain, while the increase is comparatively slight in tho 

 blood of the femoral vein. The proportion of cholesterine is also large in the arterial 

 blood, as compared with other observations. 



Experiment IV. shows but a slight difference in the quantity of cholesterine in the 

 arterial blood in the two animals ; the proportion in the animal that was etherized being 

 0-774 per 1,000, and in the animal that was not etherized, 0'768 per 1,000, the difference 

 being but 0-006 ; but, as was suspected, the ether seemed to have an influence upon the 

 quantity of cholesterine absorbed by the blood in its passage through the brain. In the 

 first instance the increase was but 3-488 per cent., while in the latter it was 23-307 per 

 cent. 



The natural conclusions to be drawn from these observations, with regard to the ori- 

 gin of cholesterine in the economy, are the following : It has been ascertained that the 

 brain and nerves contain a large quantity of this substance, which is found in hardly any 



