ADDITIONS AND NOTES TO VOL. II. 543 



The action of amygdalin, when injected into the blood, is there- 

 fore never injurious, since no prussic acid is formed. 



Salicin generally undergoes a change corresponding to oxidation 

 in the organism ; and it is only when taken in very large quantity 

 that a portion of it passes undecomposed into the urine. The 

 experiments instituted by myself as well as by Ranke"* on the 

 metamorphosis of salicin, give the following results: after the 

 introduction of salicin into the body by the mouth, we find in 

 the urine not only salicylous and salicylic acids, but also saligenin, 

 while no sugar and no phenylic acid can be detected (see p. 238 of 

 this volume). The salicin must be for the most part decomposed 

 in the blood, for whenever I have injected a solution of this 

 substance into the jugular vein in rabbits, substances were found 

 in the alcohol-extract of the urine which yielded, with the per- 

 salts of iron, the blue colour corresponding to saligenin and 

 salicylous and salicylic acids. 



(51) Addition to p. 422, line 3. I have recently observed 

 in the same individual that the urine was expelled in nearly 

 alternating jets from the two ureters four minutes after he had 

 taken half an ounce of acetate of potash, while the urine became 

 alkaline in the course of seven minutes. In the meanwhile it 

 ought to be observed that the constitution of the individual 

 probably exerts some influence on the rapidity with which such 

 substances are transmitted into the urine, and that in this patient 

 the rapidity may have been unusually great. I certainly have 

 never found, in any of the numerous experiments conducted in my 

 laboratory, that such substances as iodine, ferrocyanide of potas- 

 sium, and alkaline carbonates, passed so rapidly into the urine as in 

 either the older or more recent observations made on this person. 



(52) Addition to p. 426, 12 lines from the bottom. Fat, how- 

 ever, sometimes occurs in perfectly normal urine. I found that it 

 was constantly present, although in small amount in the urine of 

 tortoises ( T. gr&cd] ; Frerichsf commonly found it in the urine of 

 cats, and the subsequent carefully conducted investigations of 

 LangJ confirmed this observation. The latter observer also 

 detected a small amount of fat in human urine, especially after the 



* Journ. f. pr. Chem. Bd. 56, p. 1-11. 



f Die Bright'sche Nierenkrankheit. u. deren Behandl. Braunschw. 1851, 

 S. 154. 



J De adipe in urina et renibus diss. inaug. Dorp. Liv. 1852. pp. 6-46. 



