384 



Messrs. Parkes and Wollowicz on the Effect of [May 19, 



Our conclusion is quite contrary to the observations formerly made on 

 this subject, which indicated that nitrogen is largely retained in the body 

 when alcohol is used, and that in this way alcohol both increases assimila- 

 tion or, when food is deficient, saves the tissues from destruction and hus- 

 bands strength. Whatever may be the casein febrile diseases (and on this 

 point the evidence is defective), we are quite certain that this is not true 

 for health, and that as long as the ingress of nitrogen is the same, 8 ounces 

 of absolute alcohol and 12 ounces of brandy, containing nearly ti ounces of 

 alcohol, have no effect, or a trifling effect, on the processes which end in 

 the elimination of nitrogen by the urine, and most decidedly do not lessen 

 the elimination *. 



The Phosphoric Acid, Chlorine, and Free Acidity of the Urine. 



The phosphoric acid was determined by nitrate of uranium, the chlorine 

 by nitrate of silver, the acidity by the graduated alkaline solution c — 



* It may be noted with regard to the two processes for determining nitrogen, viz. 

 precipitation by Liebig's memiric nitrate and burning by soda-lime, that the mercuric 

 nitrate throws down other nitrogenous matters besides the urea. Indeed, Yoit considers 

 (Zeitschr. fur Biologic, Band ii. p. 470) that the total nitrogen in the urine of men may 

 be safely concluded from this test. But this appears not to be so in all men. In 

 the man now experimented upon, the nitrogen by soda-lime is actually very nearly the 

 same as that calculated from the mercuric-nitrate precipitate. But in other men, and 

 even in this man now and then, the former process gave a much larger result than the 

 latter. 



It will be observed that occasionally the process by soda-lime gives a smaller result 

 than that by mercuric nitrate. The same fact is observable in the table given by Yoit 

 in the paper above referred to (p. 469). The explanation is probably this : — Possibly 

 some of the non-ureal substances thrown down by mercuric nitrate may contain less 

 nitrogen than urea, and the calculation is therefore incorrect ; but the chief cause ap- 

 pears to be the following : — Both processes are liable to error. The mercuric nitrate 

 being a colour test, is often difficult to estimate exactly ; its failure is on the side of ex- 

 cess, and the amount of failure may be 2 or perhaps 3 per cent. On the other hand, 

 the process by soda-lime has an error in the other direction : there is sometimes a diffi- 

 culty in getting off the last traces of ammonia, and there may be therefore a slight 

 error on the side of defect. If in any urine in which the amount of nitrogen by soda- 

 lime ought really to coincide with that by mercuric nitrate, but in which each error of 

 manipulation reaches its maximum limit (viz. that the mercuric-nitrate solution shows 

 more nitrogen than exists, and the soda-lime process less), the amount of nitrogen by 

 the latter plan may appear considerably less than by the former. 



