190 M. Mayer on Phosphate of Lithia, 



oxygen is replaced by chlorine ; for if so, it ought to combine 

 directly witli the metallic oxide. Oxychloride of phosphorus in 

 its compounds with metallic chlorides has the greatest similarity 

 with pentachloride of phosphorus, and ought rather to be con- 

 sidered as this body, in which chlorine is replaced by oxygen. 



Mixed with oxychloride of chromium, an action takes place 

 which may be thus expressed : — 



5PO«Cl« + 12CrO«Cl = 18Cl + 5P05 + 3Cr«0«+3Cr«CP. 



Casselmann also made experiments to ascertain the existence 

 of the oxygen radical, assumed by Gerhardt to exist in oxy- 

 chloride of phosphorus. He was led to the conclusion, that, as 

 is the case with the compounds of phosphorus with chlorine, 

 phosphorus is the only electro-positive element. 



Casselmann is making similar experiments with the chloride of 

 benzoyle, C^* H^ 0*, CI, and the chloride of acetyle, C^ H^ 0^ CI. 



Berzelius described a double salt of phosphate of lithia and 

 phosphate of soda obtained by mixing a lithion salt with 

 phosphate of soda. This was used for the detection and esti- 

 mation of lithia until Rammelsberg showed that the composi- 

 tion of the salt varied materially. He viewed it as 



SNaOl PQ5 

 3LiO J^^ ' 



and considered the two bases as isomorphous and capable of 

 replacing each other. 



Mayer* made numerous atten^ts to prepare this salt, but 

 invariably obtained a salt, which, after being well washed out, 

 was tribasic phosphate of lithia. 



Phosphate of lithia forms a heavy white crystalline powder, 

 similar in appearance to phosphate of soda and magnesia. It 

 is soluble in 2539 parts of pure water, and in 3920 parts of 

 ammoniacal water. Mayer founded on the insolubility of this 

 salt a process for the separation of lithia from the other alkalies, 

 which, if it does not satisfy all the requirements of a good 

 analytical method, seems better than the methods usually 

 employed. 



Kopp has an article f on the boiling-points of corresponding 

 chlorine and bromine compounds, and on the formulse of silicium 

 and titanium compounds, which bear especial reference to a recent 

 paper by Hofmann on the formulse of titanium compounds. 



In comparing the boiling-points of various corresponding 

 bromine and chlorine compounds, Kopp was led eight years ago 

 to the conclusion, that the former, when they contain Br^, in the 



♦ Liebig's Annalen, May, p. 193. t Ibid. p. 266. 



