255 



is most liable to calculus affections. Now, the urine of 

 healthy children is always found more acid than that of 

 adults; generally, in the proportion of tAvo to one. Whilst 

 several drops of the latter are requisite to redden a given 

 quantity of infusion of litmus, a single drop of the former 

 turns it t6 a clear red. Paper, stained with an infusion of 

 turmerick, and reddened by an alkali, was immediately 

 restored to its colour, by a single immersion in the urine 

 of children: an effect, which required some time in that 

 of adults. And that this should be the case, %ve will not 

 be so much surprised at, when we consider the nature of 

 their diet; and that, in addition to the phosphoric and 

 -uric, their urine contains the benzoic acid in considerable 

 quantity: the propoi'tion of which is found afterwards pro- 

 gressively to diminish with their advancement in life. 



The constant opportunity I have, of attending to those 

 subjects, enables me to say, that the urine of gravelly 

 patients, when fresh rendered, nay, after standing many 

 hours, in a temperature of sixty degrees, is relatively more 

 acid than the healthy; sometimes as much so as the gouty; 

 and frequently continues so, even after depositing its gra- 

 velly matter. An exception to this, however, sometimes 

 occurs in gouty habits; their urine depositing copiously 

 this acid substance, and yet manifesting no increased, but 

 sometimes rather decreased acescency: for, Avith them, a 

 considerable diminution of the quantity of the usually ex- 

 created super-acidulated phosphoric salt often takes place, 

 as shall be fully explained upon another occasion. 



K k ^ Having 



