Tlje whole experiment strikes us strongly ^ith a sem- ^^'J'^j^'^^'^^^/ 

 blance of what probably passes, under similar circum- tions on uxinej 

 stances, in nature ; and reminds us of the danger atten- ^^' 

 daut upon acid impregnations, more particularly at bed- 

 time, M^hen the urine, by many hours retention and quiet, 

 has ample time to deposit its uric acid contents in the blad« 

 dor. From it, also, we learn, that the temperature of the 

 human body, in place of retarding or prerenting (as might 

 be expected a priori) these pernicious effects, rather pro- 

 motes them, and that to a considerable degree. 



But whilst we endeavoured to establish this point, from 

 practical observation as well as experiment, we seem to 

 have entirely forgot, that the urine itself is an acid liquor ; 

 and that, therefore, if acids were so prejudicial, it is not 

 probable, that the provident wisdom of nature would Com- 

 mit the discharge of this necessary excretion to a fluid, 

 which, by prematurely separating it within the body, would 

 completely defeat the object of her humane attention. And 

 would she not, in the infinity of her resources, dispose of 

 it by some less objectionable emunctory ? 



I would, in the first place, observe, that though healthy 

 urine manifests the properties of an acid liquor, it is in 

 the very smallest possible degree; so much so, that though 

 mentioned long since, by Moraung, Coldevillars, and other 

 surgeons, yet it was not, either chemically, or medically, 

 acknowledged to be so, until the time of Scheele, who 

 finally established this point, as well as the nature of the 

 prevailing acid. And, secondly, that nothing can be more 

 erroneous, than the opinion, which so long prevailed, that 

 the phosphoric acid existed in it, in a naked or uncom^ 

 bined state. It is now well established, that it is only in 

 that of a weak acidule, or acidulous phosphate of lime, 

 very little short indeed of the point of saturation; and 

 hence the weakness of its action, as an acid liquor: for 

 were it not for litmus, and some of the more delicate of 

 the vegetable blues, we would have been, even to this day, 

 ignorant of this property; so very feeble indeed, that it 

 wiU often not affect an infusion of red cabbage, whilst 

 it turns with litmus, and, sometimes, but feebly, with this 

 most delicate of all acid tests. A single drop of phos- 

 phoric 

 2 



