£23 Scientific News., Accounts of Books, &c. 



A new edition of Parkinfon's Chemical Pocket Book, with improvements, is on the 

 point of being publiflied. 



Mr. William Henry, of Manchefter, has in the prefs, and in confiderable forwardnefs, 

 a fmall work, Intended, partly, to facilitate the acquirement of chemical knowledge to 

 perfons entering on the ftudy, without the aid of an inftruftor ; and, partly, as a portable 

 companion, for the ufe of more advanced ftudents. The firft part will contain dire£lions 

 refpefting the beft mode of ftudying chemiflry ; and, alfo, an arranged feries of experi- 

 ments, neceffary to be performed, by thofe who intend to become acquainted, by aftual 

 obfervation, with the chemical properties and habitudes of bodies. More minute direc- 

 tions will be given for conduiling thefe experiments with fuccefs, than are to be found in 

 other elementary books. The fecond part will comprize fummary inflruiSlions for the 

 analyfis (if mineral waters, and of mineral bodies in general : and the third part will point 

 out fome of the ufeful applications of chemical agents, in detefting adulterations, in dif- 

 covering poifons, &c. The work will form one fmall pocket volume ; and the author 

 thinks proper to pbferve, that it will not at all Interfere with the excellent little manual, 

 lately publiflied by Mr. Parkinfon, the plan and objedls of which are perfedly ditTerent. 



*•* J- ^* L' requefts the Correfpondents of this Journal to point out a method of ob' 

 iaining alum'woiis earth perfeSlly free from any heterogeneous mixture, and obferves, that the 

 methods pointed out by fyftematical writers are infufficient for that purpofe. As this 

 difficulty will no doubt be new to many chemifts, it would be a defirable communication 

 if he were to ftatc the impcrfe£lions which his pradice may have led him to dete£l» 



