1820.] a»d KiaminatiortvftJie Chemical Propeitm of Lit hia. Sol 



In a short time a change was perceived in the globule of mer- 

 cury. It had become larger, and had assumed a red colour ; and 

 on the under side of the globule, which was in contact with the 

 hthia, a black crust soon appeared. I put both the globule and 

 the black crust into rectified naphtha. 



I distilled off the mercury in an apparatus similar to that 

 described by Davy,, in his paper on the bases of the alkaline 

 earths. The only peculiarity in my apparatus consisted in this, 

 that from the hollow glass ball which served the purpose of a 

 receiver, there passed a tube of safety which plunged into mer- 

 cury. The whole distilled over without leaving any residue, and 

 the water in contact with which the mercury had been put did 

 not possess alkaline properties. It would appear from this that 

 the metallic basis, as fast as it was formed, had been again con- 

 verted into aia oxide. The black crust, which existed only in 

 minute quantity, was probably a mixture of suboxide of lithium 

 and oxide of mercury ; for, when heated with water, its quantity 

 was diminished, the water exhibited alkaline properties, and aix 

 oxide of mercmy remained behind. 



Sir Humphry Davy has obtained lithium, and found it to 

 resemble sodium in its properties. 



From the preceding account of the salts of lithia, we see that 

 they have many properties in common with the salts of soda. 

 Like them, they are neither precipitated by muriate of platinum, 

 nor by tartaric acid. They may, however, be distinguished I'rom 

 the salts of soda by the following properties : When their concen- 

 trated solutions are mixed with a concentrated solution of car- 

 bonate of soda, a precipitate falls. They .we likewise precipitated 

 by phosphate of soda and phosphate of ammonia, when no 

 uncombined acid is present. 



In reference to analytical chemistiy, I may remark that lithia,, 

 potash, and soda, if they should exist in the same compound, 

 may be separated in the following way : 



Lithia may be precipitated by means of phosphoric acid and an 

 excess of caustic ammonia. The phosphate of lithia may be 

 dissolved in acetic acid, and the phosphoric acid precipitated by 

 means of acetate of lead, &c. 



When lithia exists in a compound along with potash, this last 

 alkali may be precipitated by means of muriate of platinum. 



From the results of the preceding experiments, we see that if 

 10 be the equivalent number for oxygen, the equivalent number 

 for lithium is 13-83, and for lithia •23-83 ; that for carbonate of 

 lithia by calculation 5T32 ; but, according to the preceding 

 experiments, 52-32 j Sec. 



