322 Progress of' Foreign Science. 



of oxygen ; if, on the other hand, the ratio of the oxygen of the 

 oxide were to that of the acid as 2 to 5, the oxide ought to con- 

 tain only 20 parts of oxygen. If, finally, the oxygen of the oxide 

 were to that of the acid in the ratio of 3 to 5, its composition 

 would recede equally from the result obtained by experiment*." 

 As Dr. Wollaston's scale coincides for muriate of silver with 

 Berzelius's atomic numbers, we shall employ it in the examina- 

 tion of the above passage ; 15.61 muriate of silver coiatain 2.98 

 of what Berzelius still reckons muriatic acid, which were pre- 

 viously combined with the 3.05 of oxide of chromium. And 

 2.98 : 34.12: :3.05:: 34.92, a number representing, by Berze- 

 lius's experiments, the equivalent of oxide of chromium, on 

 Dr. Wollaston's scale. And 2.98 : 3.05:: 100 : 102.3, pre- 

 cisely as M. Berzelius has stated. He adds, " which makes 

 28.5 parts of oxygen in 100 parts of green oxide ;" hence, by 

 proportion, in 3.05 parts 0.869, and in 3.49, or (to bring the 

 atom to round numbers), in 3.5 parts, almost exactly 1 of oxy- 

 gen. Thus the atom of chromium would appear to be 2.5, that 

 of the green oxide 3.5, and that of the acid 5.5, the latter num- 

 ber of which is quite discordant with that deduced from his 

 experiment on chromate of Icadf, which gave 213.924 oxide of 

 lead to 100 of acid ; whence the latter becomes on the equiva- 

 lent scale 6.54. One of the canons of combination laid down 

 by Berzelius is, that 100 parts of muriatic acid neutralize a 

 quantity of base, which contains 29.4 of oxygen, and from this 

 canon his above calculation seems to be made. Now, this 

 proportion is precisely what we find by sliding 100 on Dr. 

 Wollaston's scale opposite to dry muriatic acid, for 29.4 is then 

 opposite to oxygen. In like manner, by sliding 100 opposite to 

 each other body on that instrument we may make as many 

 canons as we please, but they all merge in the general system 

 of equivalents. Dr. Thomson, in his account of the atomic 

 theory I, says, " According to Berzelius in order to saturate 

 100 parts of muriatic acid, a metal must be combined with 42 

 parts of oxygen." We shall not attempt to unravel this atomic 

 knot. While we entertain the highest respect towards the 

 Swedish chemist for his unwearied and valuable researches, we 

 cannot help thinking his manner of viewing chemical propor- 

 tions to be unaccountably perplexed and defective. We can 

 more easily understand why his partial mode of notation should 

 be preferred by many writers in France to the universal sys- 

 tem, as taught by J\Ir. Dalton, and so clearly exhibited on Dr. 

 Wollaston's scale, for the same reason that vaccination was so 

 ill received in that country, — because it was discovered by an 

 Englishman. 



We are lately indebted to Professor Berzelius also, for a 



* Annalcs de Chimic et de Physique, Tom. xvii. p. 10. 

 f Ibid. Toiu. xvii. p. 7. % Annals of Phil. u. 6D. 



