1825.] M. Bevzelius's Hypothesis of the Atomic Theonj. 191 



manner the quantity of sulphuric acid and of silica, respectively 

 combined with the alumina, is triple that combined with the 

 potash. In the double tartrate of potash and soda, the two alka- 

 lies contain the same number of atoms of oxygen, and are conse- 

 quently combined with the same number of atoms of tartaric 

 acid. 



When two salts, having a common base but different acids, 

 combine, the number of atoms of oxygen of ttie portion of base 

 combined with one of the acids is a multiple by a whole number 

 of the number of atoms of oxygen in the portion of base com- 

 bined with the other acid ; or, the number of atoms of oxygen 

 in one of the salts is a multiple by a whole number of the atoms 

 of oxygen in the other. We have an instance oi this species of 

 combination in datholite, a compound of borate and sihcate of 

 lime, in which the lime is equally divided between the two acids ; 

 whilst in the blue carbonate of copper, the quantity of base 

 combined with the carbonic acid is twice as "reat as that com- 

 bined with the water. 



In organic bodies, the compound atoms of the first order 

 contain at least three elements, oxygen, hydrogen, and carbon ; 

 and their atoms are capable of combining m all sorts of propor- 

 tions, so that neither of them can be taken as unity with refer- 

 ence to the rest. But when org-anic atoms of the ttrst order 

 combine with compound inorganic atoms of the first order, as 

 when a vegetable acid combines with an oxide, they follow the 

 same laws that regulate the combinations of the compound inor- 

 ganic atoms, and the oxygen of the organic atom is a multiple, 

 or sometimes a submultiple, by a whole number of the oxygen 

 of the compound inorganic atom. Hence these combinations 

 present the same phenomena of definite proportions as those of 

 inorganic nature, and it is only in the formation of organic atoms 

 of the first order that combination is possible in all sorts of pro- 

 portions. 



In the earliest experiments with the voltaic pile, it was found 

 that the common salt, a solution of which was usually employed 

 to moisten the [lasteboard discs interposed between each pair of 

 metallic discs, became decomposed by its action ; and about 

 the year 18U5, MM. Hisinger and Berzelius published their 

 experiments on the galvanic decomposition oi' the muriates of 

 ammonia and lime, and several other neutro-saline solutions. 



The results of those experiments demonstrated that when 

 electricity traverses a saline solution, or any other liquid con- 

 ductor, its elements are separated in such a manner that some 

 collect round the positive, and others round the negative pole ; 

 and that oxygen, acids, and oxidated bodies, terminate to the 

 former, whilst combustible bodies, alkalies, and the earths find 

 their point of rest at the latter. 



On the '2()th of November, 18()'i, Sir Humphry (then Mr.) 



