260 



much, at one time,.recommeaided. by Doctors Percival and 

 Saunders, previous to its more modern alkaline combina- 

 tion, in our mephitic, as well as super-aerated soda waters. 



Into the middle part of Nooth's apparatus, wero intro- 

 duced four pounds of fresh rendered healthy urine, and 

 exposed to a stream of carbonic acid gas. After a few 

 hours, a copious and beautiful precipitation of uric crys- 

 tals took place, (notwithstanding the constant agitation, 

 from the transmission of the gazeous bubbles,) larger than 

 any I before observed, that from the tartarous. acid ex- 

 cepted- In a standard quantity, no distinct crystalliza- 

 tion, even after two days. A repetition of the same ex- 

 periment afforded similar results. 



EXPERIMEMT X. 



Finding the carbonic acid gas productive of similar ef- 

 fects, with the other acids hitherto examined; it was na- 

 tural to inquire, how far its combination with the portion 

 of alkaline mattei', contained in our mephitic and soda 

 waters, so highly surcharged with it, may prevent a sepa- 

 ration of this uric acid. 



Half an ounce, only, of the common soda water of the 

 shops, prepared by Mr. Kinsley, was added to four ounces, 

 of healthy urine. A similar quantity was impregnated 

 with carbonic acid gas. In the former, after forty-eight 

 hours, or more, no more than the usual nubecula: nor 

 could a single crystal be discovered, even by a magnifier. 

 In the latter, an early, copious, and beautifal crystalhza- 



tion. 



