186 Mr. Children's Summary View of [March, 



denoted by the symbols, of the illustrious Professor of Stock- 

 holm. 



A short account of his doctrine will, therefore, probably not 

 be uninteresting to our readers, though, perhaps, they may think 

 with us, that tlie simpler theory usually adopted in our own 

 country answers every purpose equally well, and with greater 

 facihty, than the more complicated system of our continental 

 neighbours. But our object is to explain, and nut to criticise. 

 We proceed, therefore, to the details ; which are partly ab- 

 stracted from Berzelius's Eami sur la T/ieorie des Proportions 

 Chimiques, and his Nouveaii Si/steme de Miiieralogie, and partly 

 from the work lately published by M. Beudaut, entitled Trailer 

 Elementaire de Mitieralogie. 



Berzelius has candidly admitted in the introduction to his 

 Essai, that he has indulged largely in conjecture respecting the 

 latent causes which regulate a few facts, and the laws that deter- 

 mine them ; and that he attaches no further importance to those 

 conjectures than conjectures generally deserve. As to his 

 theory, however, respecting chemical proportions, he speaks 

 with more confidence. " 1 here confine myself within the circle 

 of experiment ; and the laws which 1 have endeavoured to esta- 

 blish are the general result of experience derived from that 

 source." 



From the moment that bodies were considered as formed of 

 simple elements, it seems to have been generally assumed, that 

 similar external characters and internal properties indicate simi- 

 larity of composition both in the nature and proportion of the 

 elements of which compound substances are formed. A German 

 chemist of the name of Wenzel appears to have been the first 

 who attempted to establish the truth of this assumption, by an 

 experimental investigation of a phenomenon which had already 

 excited attention, namely, that when two neutral salts mutually 

 decompose each other, the resulting compounds are also neutral. 

 He showed that the relative proportions of alkalies and earths 

 which saturate a given quantity of the same acid, are the same 

 for all other acids ; if nitrate of lime, for instance, be decom- 

 posed by sulphate of potash, the nitrate of potash and sulphate 

 of lime which result from their mutual action preserve their 

 neutrality ; for the quantity of potash vviiich saturates a given 

 qaantity of nitric acid, is to the quantity of lime which saturates 

 the same quantity of nitric acid as the quantity of potash is to 

 that of the lime which saturates a given quantity of sulphuric 

 acid. Bergmann also bestowed much attention on the develop- 

 ment of chemical affinities, but we are principally indebted to 

 Richter for the first positive indications of chemical proportions 

 derived from numerous experiments. He examined the pheno- 

 menon noticed by Wenzel, and explained it in the same way ; 



