SUGAR. 287 



described methods into tied loops of intestine, when an augmenta- 

 tion of the normal quantity of sugar was constantly found in the 

 blood ; in some cases it even rose to 0*6 , and could therefore be 

 detected in the urine (see note to vol. ii, p. 427, in Appendix). 

 The same results were obtained from a second series of experi- 

 ments on rabbits, in which solutions of sugar were injected 

 through the oesophagus into the stomach. The value of the 

 experiment was often diminished by the circumstance that the 

 abnormal distension of the intestine with an aqueous fluid loaded 

 with sugar induced morbid phenomena and interfered very con- 

 siderably with the resorption of the sugar. The third method of 

 detecting the direct passage of the sugar into the blood, consisted 

 in allowing the animals a free supply of highly saccharine food. 

 In this case also there was found to be a constant augmentation of 

 the quantity of sugar in the blood ; it was, however, only when 

 the animals had been very voracious that any sugar could be 

 observed to have passed into the urine. Thus there can be no 

 doubt that a great part of the sugar taken with the food or formed 

 in the intestine during digestion, passes unchanged into the blood : 

 and hence, although sugar is also formed in the liver, the quantity 

 of this substance in the blood is directly proportional to the 

 quantity of carbo-hydrates that have been taken a fact which 

 Bernard* has been led to deny, from his determinations of the 

 amount of sugar in the livers of various animals, although his own 

 investigations show that the liver of herbivorous animals and birds 

 always contains more sugar than those of carnivorous animals. 



Another question of much importance in relation to the 

 resorption of sugar is, regarding the quantity which an animal of 

 known size or weight can take up in a given time. Boussingaultf 

 found, in his experiments on ducks, that one of these birds (the 

 weight not being stated) was able to resorb 5*62 grammes of 

 sugar, or 5*26 grammes (the equivalent quantity) of starch in one 

 hour. Von Becker found, in several experiments in which saccha- 

 rine solutions were injected at intervals of a quarter of an hour into 

 the stomachs of rabbits, that for every kilogramme's weight of the 

 animal there were about 4*5 grammes of sugar absorbed in the hour. 

 No importance should, however, be attached to this determination, 

 since, as we learn by direct experiments, the quantity of sugar 

 resorbed in a given time is very dependent on the concentration of 

 the saccharine solution in the intestine. 



* Nouvelle fonction du foie, p. 48. 



t Ann. de Chim. et de Phys. 3 S&-. T. 18, p. 400. 



