286 DIGESTION. 



the intestine, but that it very soon undergoes still further altera- 

 tions, seems to present a greater probability than the assumption, 

 that it is merely on account of its great solubility and diffusibility 

 that it passes with extraordinary rapidity into the mass of the 

 blood. But is the diffusibility of sugar actually so great? 

 Graham's experiments, which were instituted with crystallised 

 and fused cane-sugar as well as with glucose, coincide in this 

 point, that sugar has less than half the diffusibility of chloride of 

 sodium; while 58'7 parts of salt are diffused, only 26*6 parts of 

 sugar are diffused under precisely the same conditions. Moreover, 

 the endosmotic experiments which have been made by Jolly and 

 others entirely correspond with the above results ; thus, Jolly 

 found the endosmotic equivalent of sugar to be almost twice as 

 great as that of chloride of sodium, and twenty times greater than 

 that of hydrated sulphuric acid. Hence these ph} r sical experi- 

 ments do not by any means justify us in concluding a priori that 

 the resorption of sugar in the intestine is an extraordinarily rapid 

 process. 



Amongst the numerous contradictions which we meet with in 

 the consideration of the phenomena connected with the behaviour 

 of sugar in the intestinal canal, it seems to be especially necessary 

 to institute further and more accurate investigations regarding this 

 circumstance. Several series of experiments have been carried on 

 at my suggestion by von Becker* on rabbits, which at all events 

 have thoroughly cleared up some of the points in question. I 

 deemed it necessary to put aside for the time the consideration of 

 starch, cane-sugar, &c., and to employ only that sugar in these 

 experiments which is formed in the animal body from these 

 carbo-hydrates before they undergo resorption. In the considera- 

 tion of the results of Becker's experiments even this point must 

 not be wholly overlooked ; for we have introduced into the 

 intestinal canal and the blood far more sugar than is ever found 

 there during the digestion of the amylacea under normal relations; 

 and from this very circumstance several objections have arisen 

 which affect not only Becker's investigations, but likewise several 

 experiments made by myself or Uhle. In the first place, it was 

 established beyond all doubt, by three series of experiments, that 

 after the introduction of large quantities of grape-sugar into the 

 intestinal canal, this substance passed directly into the blood, 

 where, indeed, it often accumulated in such large quantity as to 

 show itself even in the urine. In the first series, saccharine 

 solutions of various strengths were introduced by the previously 

 * Zeitschr. f. wiss. Zool. Bd. 5, S. 123. 



