VOL. LXXXVIII.] PHILOSOPHICAL TRANSACTIONS. 'i()5 



bonateof ammonia amounted to 20grs.; and it was black empyreumatic animal 

 oil which stained the tube. 



This experiment was repeated, on 120 grs. of a nut-brown, very light, urinary 

 concretion. The result was not very different from that of the former experiment, 

 except that the gaz contained a portion of hydrogen gaz. There were 30 grs. of 

 the above described spicula, principally mixed with carbonaceous matter: they were 

 light, and had only a very slight sharp and bitter taste. The experiment repeated 

 a 3d time, with 80 grs. of urinary concretion, afforded 15 grs. of the white spicula 

 above described, mixed with carbonaceous matter. These I found did dissolve in 

 a large proportion of muriatic acid; which solution yielded them, on evaporation, 

 in the same state as before. Under the flame applied by the blow-pipe, they first 

 melted, and then evaporated, without any smell; leaving a slight black mark. 

 Turnsole was reddened by these spicula. In a 4th experiment, I found the white 

 spicula contained in the carbonaceous matter united, on boiling, with carbonate of 

 soda, as well as with caustic soda; but, as before, muriatic acid precipitated nothing 

 from the solution. These spicula could not be dissolved in nitric acid; nor did the 

 solution of them in water become turbid with oxalic acid. Their taste was, as 

 before, rather bitter and sharp than sour. A very suffocating smell issued forth, 

 on breaking the tube used in this experiment, but it was not from sulphur, nor 

 from prussic acid. 



These experiments afford evidence of the wide difference between the animal 

 oxide above described and the acid sublimate of Scheele.* If this conclusion be 

 allowed to be just, it will be necessary to give a name to this urinary animal oxide. 

 Agreeably to the principles of the new chemical nomenclature, the name should 

 be lithic oxide. But the term lithic is a gross solecism; and I trust that philolo- 

 gical critics will find the name ouric or uric oxide perfectly appropriate; for, if it 

 be thought objectionable, on account of the existence of the matter in arthritic as 

 well as urinary concretions, still philology will allow its admission, as in other 

 similar cases, x»t i^o^v ; it being found in greater abundance, by far, in the uri- 

 nary passages, than in other situations, and therefore falling under common ob- 

 servation as an ingredient of the urine. If however the term of lithic oxide, or 

 any other denomination, shall obtain acceptance, I shall very willingly adopt it. 



It requires no sagacity, in a person acquainted with the facts of the preceding 

 experiments, to perceive that they are applicable to a variety of uses in chemical 

 investigation, and in the practice of physic. The latter I of course take no notice 

 of in this place; but, relative to the former uses, I shall particularly point out, 

 that we are now able not only to detect, in the easiest manner, the presence of 



* From these experiments, it now appears very doubtful whether the lithic acid of Scheele exists as 

 a constituent of urinary concretions, or is compounded, in consequence of a new arrangement taking 

 place, of the elementary matters of the concretion, by the agency of fire ; but it is demonstrated, that 

 the urinary animal oxide is really a constituent part, and even a principal one, of almost all human 

 urinary calculi.— Orig. 



vol. xviii. Mm 



