Neiv Ptlhlkallom, 26<} 



Vkw of the Laws to which Light and Heat> or rather the 

 rays which occafion thciii, are ful)jc6l, in order to determine 

 whether they are the fame or different. Part TT. By Wil- 

 liam Ilerfchel, ^X.D. F. R.S. And, An Account of the 

 Trigonometrical Survey carried on in the years 1797, 1798, 

 and 1799, by order of the Marquis Cornwailis, mailer-gc- 

 ueral of the ordnance. By Captain William Mudge, of the 

 Royal Artillery, F.K.S. Communicated by his Grace the 

 Duke of Richmond, F.R.S. 



The P/jjjtcal Pr'mciphs of Chemijlry, By M. J. Brisson, 



Memhtr of the Trench National Inflilute^ and Vrrfefjor of 

 Chem'ijlry in the Central School of Paris, Tranjlated frovi 

 the French, llliijlrated with Etngravings, 8co. Cuthell, 

 and V^ernor and Hood. 



THE prefent work contains much ufeful" matter, well di- 

 gefted, well arran^x'd, and comprefTed into as little bulk as 

 its nature could admit of, without omitting any thing necef- 

 fary in an elementary treatife. 



The tables of the combinations of all the acids with the 

 falifiable bafes. In the order of their affinities, io far as 

 yet known, are fo ample that the work cannot fail to prove 

 extremely ufeful even to thofe who are well acquainted with 

 chemidry; and the various procelfes, which are detailed w-ith 

 precifion, yet without prolixity, are illuftrated with engrav- 

 ings of the necelTary apparatus, executed in a maftcrly man- 

 ner by Lowry. . . 



The work poflefles confiderable merit, and the tranflation 

 is well executed. The following extract, will ferve as a fp?- 

 cimcn of both : 



^' Nitrous Gas. 



*' Nitrous gas was difcovered by Hales ; but Pricftley 

 made known the greater part of its properties. It docs not 

 cxift in a natural Hate, and mu(l be obtained by the afliit- 

 ance of art. It is one of the conllitiient parts of the nitrous 

 flcid ; and it wouM be nitrous acid itfelf, were it not de- 

 prived of a large portion of its oxygen, which makes it ceafe 

 to be an acid. It is compofed .with the fame bafe as that of 

 ihe nitrous ,acid^ which is azot holding in a ftate of gas two 



parts 



