16 RISE AND PROGRESS OT CHEMISTRY. 



rection of Sir Humphry Davy, and been described in his lectures, 

 as ch< mical professor to the stablishment, has acquired a very dis- 

 tinguished reputation. To this have succeeded several other sci- 

 entific institutions in this metropolis, which have, in dili-r. nt de. 

 grees, contributed towards the same object ; the Geological Soci- 

 ety, and the Wernerian Society of Edinburgh ; both which, more 

 especially, have been labouring for some years, in the immediate 

 department to which the observations before us are peculiarly di. 

 reeled. From these, and similar establishments, and more parti- 

 cularly from the successful labours of Sir Humphry Davy, we have 

 obtained a more comprehensive insight into the principles of bodies ; 

 have assured ourselves, that many of the earths are only metallic 

 oxyds, which may be reduced to a reguline or pure metallic state, 

 by detaching the oxygen, which alone gives them their oxyd form ; 

 and have hence been led to believe, that all the other earths, which 

 have not yet been analyzed with the same success, are formed of 

 similar principles. We have been able to decompose the fixed alka- 

 lies ; have made no small progress in decomposing ammonia, and 

 the simple combustibles ; and have ascertained the very singular 

 fact, that the first of these, whether potash or soda, are themselves 

 metallic oxyds, capable of being reduced, by an abstraction of their 

 oxygen, to metals of an extraordinary character, their levity ena- 

 bling them to float not only upon water or alkohol, but in one in* 

 stance upon naphtha, the lightest fluid we know of. We have also, 

 from the same sources, discovered that oxygen is by no means 

 the only simple supporter of combustion ; that there are at least 

 two other substances, chlorine and iodine, (and we have reason 

 to believe there are more) which make a near approach to it in 

 this and various other respects: and which, at the same time have 

 a peculiarity of character that seems to establish them as distinct 

 bodies. 



[Editor. 



