130 On Sir fl. Davys Theory qf [Aug. 



which I estimated by the formation of muriate of silver, found- 

 ing my calculations on the analysis of that salt given by Proust.* 

 7*5 cubic inches, or 5*43/5 grs. of the gas were agitated with 

 distilled water, until it had absorbed the whole. Nitrate of 

 silver was then added, and, after being several times agitated, 

 the phial was set aside in a dark place for 24 hours. The mixture 

 of muriate of silver and acid liquor was then thrown on a filter, 

 previously dried with care, and weighed, and the residuum was 

 washed with distilled water, until it passed through tasteless. 

 The filter with the muriate of silver was next wrapped up, and 

 laid in a dark place, having a temperature of about 70°, until it 

 appeared perfectly dry. It was then found to have gained 

 between 22*5 and 23 grains. 



According to the old theory, 5*4375 grs. of oxymuriatic gas 

 should be resolved into 1*323467 gr. of oxygen, and 4*114033 

 grs. of muriatic acid, which can combine with 19*28073 grs. of 

 oxide of silver, forming 23*394763 grs. of muriate. 



In consonance with Sir H. Davy's views, the chlorine and the 

 silver combine, while the oxygen previously in union with the 

 silver is set at liberty. Now 5*4375 grs. of chlorine are capable 

 of forming, by union with hydrogen, 5*64645 grs. of muriatic 

 acid, which can in their turn produce 31*37917 grs. of horn 

 silver; therefore 5*4375 grs. of chlorine are capable of forming 

 31*37917 grs. of horn silver. 



To this experiment it may be objected, that, if Sir H. Davy's 

 theory be correct, the analysis of muriate of silver assumed must 

 be incorrect in regard to proportions. This objection it will be 

 necessary to examine somewhat minutely. The proportions of 

 acid assigned to the salt by the analyses of Gay-Lussac and 

 Thenard, f Berzelius. % Rose, Proust, Zaboada, Chenevix, and 

 Kirwan, § do not differ from each other more than between 

 19*44 and 16*54. Of these I have in this paper preferred that 

 of Proust, which is very nearly the mean of them. If, then, 

 100 grs. of muriate of silver yield, on analysis, 18 grs. of muriatic 

 acid and 82 grs. of oxide of silver, it seems probable that it 

 contains 17*323 grs. of chlorine, united to 7^*6 grs. of silver. 

 But this supposition leaves a deficiency of 7'077 g rs - 5 ar) d to 

 fill up this we must suppose the salt to contain a proportion of 

 water, which, being decomposed during its analysis, yields its 

 oxygen to the silver, and its hydrogen to the chlorine. Now 

 75 - 6 grs. of silver take 6-4 grs. of oxygen, which can combine 

 with 1*07 gr. of hydrogen, while 17*323 of chlorine cannot 



* Journal de Phys. xlix. p. 221. + Rech. Phys. Chim. ii. 123. 



% Ann. de Chim. lxxix. 133 ; lxxviii. 11-1; lxxvii.84. 

 (, See Dr. Thomson's System of Chemistry, iii. 153. 



