364 THE KOYAL INSTITUTION. [CHAP. VI. 



Oxygen, and on the Chemical Kelalions of these Princi- 

 ples to Inflammable Bodies.' 



In the first paper he says, ' Scheele considered 

 oxymuriatic acid as more simple than muriatic acid, 

 and that it became muriatic acid by union with 

 phlogiston. Berthollet said it contained oxygen. 

 The vivid combustion of many bodies in this gas has 

 favoured the presumption that it contained oxygen very 

 loosely combined, and ready to exert its utmost power 

 of affinity ; but it is mere presumption, since heat and 

 light result also from the intense agency of any other 

 combination without the presence of oxygen.' 



On July 3 he wrote, ' Equal parts of oxymuriatic acid 

 and hydrogene, both dried, were detonated. There was 

 a diminution equal to about y^, and muriatic gas was 

 formed ; and this was over mercury, and some of the 

 oxymuriatic acid burnt the mercury, and there was an 

 excess of J hydrogene. Equal parts of oxymuriatic 

 acid and sulphuretted hydrogene, diminution about --. 

 Muriatic gas formed; sulphuretted hydrogene ap- 

 parently in excess.' 



A most important experiment had be^n made on 

 September 21, 1809, on the resistance of oxymuriatic 

 acid to galvanic decomposition ; and as long previously 

 as April 19, 1808, he had decomposed muriatic acid 

 with a battery of 520 pair of plates. 1 



1 The discovery of the simplicity of chlorine was claimed by the 

 French chemists; Davy afterwards said of Gay-Lussac's paper in the 

 Annales de.Chimie for July 1814, ' The historical notes attached to it are 

 of a nature not to be passed over without animadversion. M. Gay-Lussac 

 states that he and M. Thenard were the first to advance the hypothesis 

 that chlorine was a simple body, and he quotes M. Ampere as having 



