1872.] 



in the Urine in Health and Disease. 



363 



of Nessler's solution, and then compared with the tint-depth produced by 

 known quantities of ammonia in a similar bulk of liquid treated with the 

 same solution. The trace of ammonia in the water itself must be always 

 allowed for. The external temperature in the observations was always 

 about 62°. 



They regard 60 oz. as the normal daily excretion of urine in adults. 



T. Ammonia in Health. 

 In 50 cases the average quantity of ammonia 



=0*0825 gr. in 1000 grs. =2*1656 grs. per diem. 

 The 10 highest cases gave an average of 



0*1620 gr. per 1000 grs. =4*2525 grs. per diem. 

 The 10 lowest cases gave an average of 



0*0252 gr. per 1000 grs. = 0*6615 gr. per diem. 

 The mean of these 20 cases gives 



0*0936 gr. per 1000 grs. = 2*457 grs. per diem. 

 The authors conclude that the average daily excretion of ammonia in 

 health amounts to rather less than 2*5 grs. in 24 hours. 

 These results are modified by : — 



1st, age. The amount of ammonia was largest under the age of 35 years, 

 to the extent of a little over one third. 

 2nd, sex, but very slightly (?). 



3rd, food. The amount of ammonia after meals was nearly double that 

 excreted before meals. Their experiments seem to prove that a large 

 proportion of the urinary ammonia is derived from the food ingested ; con- 

 firmed by other experiments. 



4th, atmospheric conditions. The authors consider that the excretion 

 of ammonia by the kidneys is governed by a similar law to that which 

 regulates the formation of dews. 



5th, exercise increases the excretion of ammonia. 



II. Ammonia in Disease. 



Before dealing with special diseases, the authors examined the influence 

 of some general conditions both of the urine and the patients. 



A, colour of the urine. (Vogel's colour-scale was adopted.) From No. 1 

 to No. 7 the ammonia rises in proportion to colour (jaundice and hsema- 

 turia being excluded). True also, to a great extent, of normal urine. 



B, specific gravity of the urine. The general rule is that the excretion 

 of ammonia keeps pace with the specific gravity. 



C, pulse. The lowest quantities were met with when the pulse was 

 rapid, the highest average being met with when the pulse was nearly 

 normal. 



D, respirations. It appears that the amount of ammonia decreases 

 with accelerated respirations. 



E, temperature (axillary). The largest excretion per 1000 grains is 



