Origin of Muscular Power* 489 



the work urine. Again, the amount of urine secreted between 20 

 minutes past 1 and 7 in the evening was determined ; this we 

 will call simply the after-work urine. During this time we re- 

 mained, for the most part, in the house without any muscular 

 exertion worth mentioning. After 7 o'clock a plentiful meal, 

 consisting chiefly of meat, was taken, and lastly the urine ex- 

 creted during the night spent in the hotel of the Faulhorn (that 

 is to say, from 7 o'clock in the evening of the 30th till half- 

 past 5 in the morning of the 31st of August) was measured and 

 again designated night urine. Arrived at the hotel on the sum- 

 mit of the Faulhorn, determinations of the quantity of urea in 

 the specimen of the night urine from the 29th to the 30th, and 

 of the work urine excreted between half-past 5 in the morning 

 and 20 minutes past 1, shortly after the end of the ascent, were 

 proceeded with. The method followed was precisely that given 

 by Neubauer for absolute determinations of urea. 



Phosphoric and sulphuric acids were first precipitated from 

 40 cubic centims. of urine by 20 cubic centims. of solution of 

 baryta, which quantity was proved to be sufficient ; and 15 cubic 

 centims. of the filtrate ( = 10 cubic centims. of urine) were 

 employed for the determination of chlorine by Liebig's method, 

 with a solution of nitrate of mercury of which 1 cubic centim. 

 corresponded to 0*01 grm. of common salt. From 30 cubic 

 centims. of the filtrate the chlorine was then precipitated with 

 the exact amount of silver solution necessary, as indicated by the 

 amount of mercury solution previously employed. A portion of 

 the filtrate ( = to 5 cubic centims. of urine) was then employed 

 in making an approximative determination of the amount of 

 urea, and with another portion (= the 10 cubic centims. of 

 urine) an exact determination of urea was made with the neces- 

 sary mercury solution (1 cubic centim. =0*01 grm. of urea). 

 These operations were performed with every possible precaution. 



On the morning of the 30th of August we made similar deter- 

 minations of the after-work urine of the preceding day, collected 

 between 20 minutes past 1 p.m. and 7 o'clock in the evening. 

 A specimen of each kind of urine was also sealed up in a per- 

 fectly filled and well-corked and scaled bottle, in order that on 

 our return to Zurich the yet more important determination of 

 the absolute quantity of nitrogen might be undertaken ; the 

 same thing was done with the second night urine, collected and 

 measured between 7 o'clock in the evening of the 30th of August, 

 and 6 o'clock in the morning of the 31st; but the quantity of 

 urea in this, owing to want of time, was not determined. The 

 chlorine and urea determinations gave the following results : — 



I. Night urine from the 29th to the 30th of August. In both 

 cases coloured light yellow, perfectly clear, decided acid reaction. 



