18 IS.] Chlorine, and Us Compounds. \29 



much oxymuriatic gas as they can act on, ought to yield nearly 

 1 76-456 grs. of saline matter, consisting of 113176 grs. of 

 muriate, and 63'2S grs. of hyper-oxymuriate. 



According to Sir H. Davy's theory, the resulting quantity of 

 saline matter ought to he 153*188 grs., of which 117*535 grs. 

 should he muriate, and 35*653 grs. hyper-oxymuriate.* He has, 

 however, given a calculation somewhat different from this ; f by 

 which it appears that 100 grs. of potash yield 168*372 g rs - or 

 saline matter, containing 127*4 gis. of muriate, and 40*9/2 of 

 hyper-oxymuriate. 



It is only when strong muriatic acid is made to act on the salt 

 that oxymuriatic gas is obtained. It were needless to extend a 

 paper, already too long, by detailing the opposite theories of this 

 process; it may be sufficient to remark, that, according to Sir 

 H. Davy's view, hydrogen must attract oxygen more powerfully 

 than it attracts chlorine. 



Let us now examine the phenomena which present themselves 

 during the decomposition of oxymuriatic gas ; which readily 

 takes place, if water impregnated with it be exposed to the sun's 

 light. According to the old theory, the light merely separates 

 the oxygen from the muriatic acid. On the principles laid down, 

 by Sir H. Davy, the chlorine decomposes the water, uniting 

 with its hydrogen, and setting the oxygen at liberty : so that 

 here the attraction between chlorine and hydrogen muse over- 

 balance that between hydrogen and oxygen. 



According to the former of these theories, the oxygen comes 

 entirely from the oxymuriatic gas, and a quantity of muriatic 

 acid is left, equal in weight to the gas used, minus the weight of 

 the oxygen obtained. If, on the other hand, Sir H. Davy's 

 theory be correct, the oxygen is derived from the water alone, 

 and the residual muriatic acid will be equal to the weight of the 

 chlorine used, plus the weight of a quantity of hydrogen, suffi- 

 cient to form water with the oxygen given out ; while the water 

 must be diminished by a quantity equal to the weight of the 

 oxygen obtained, added to the increase in weight on the part of 

 the chlorine. 



I had an opportunity, during the summer of 1811, through 

 the kindness of Mr. Garden, of Compton-street, Soho* of per- 

 forming a few experiments on this point ; not, however, with a 

 view to ascertain whether or not the water suffered any diminu- 

 tion, but to determine the quantity of residual muriatic acid, 



• In this calculation, I have entirely disregarded the uncertainty respecting 

 tin' constitution of the peroxide of potassium, and of eachlnrioe ; and have 

 procee de d, solely on the ground that 100 of the talt give off by lien :>s47a of 



oxygen. 



f Phil. tram. 1811, p. 19. 



Vol. II. N° II. I 



