232 ON THE NEW METALS. 



been supposed from its want of philosophical precision I suspect it has ano- 

 taid to be false'. ^^^^ source) that the alkalis were long ago suspected to be 

 metallic oxides. This is not true. I have read pretty ex- 

 tensively in chemistry, without meeting with such a suspi- 

 cion. That the alkaline earths and common earths were 

 dephlogisticated metals, has been a very old doctrine; but I 

 remember no such notion with respect to potash and soda. 

 I have looked into Dr. Beddoes's Contributions; but I find 

 no idea there of the alkalis being metallic oxides ; but I 

 have met with a much more ingenious suspicion, namely, 

 that metals are compounds of hidrogen and azote, which, 

 since the metallization of ammonia, does not seem so in^pro- 

 bable. 



I am, Sir, with respect, 



Your obedient humble Servant, 



A. COMBES. 



Chelsea, Sept. 8, 1808. 



REMARK. 

 WHEN a man ventures to aflert, that a thing " is not 

 the author of true," because he " has not met with it," he must have con- 

 the preceding siderabie confidence in the universality of his reading on the 

 letter mis- subject, the unremitting attention with which he peruses 

 authors, and the infallible retentiveness of his memory. 

 Admitting however, that Mr. Combes never overlooks a 

 circumstance slightly or incidentally mentioned in a book 

 he reads, and that his memory is too tenacious, ever to let 

 slip what it had once received ; it is surely very possible, 

 that he might have wanted opportunity or inclination to read 

 every work, that may have fallen into the hands of a reader 

 much his inferior in talents; and in some of these may have 

 been suggested hints, that have hitched in a memory far less 

 tenacious than his. To speak with " philosophical preci- 

 sion** indeed, he should merely have said, that he did not re- 

 collect ever to have met with such an opinion. I can only say, 

 as the opinion that, in a book so commonly read as f ourcroy's Chemistry, 

 . «nientioned the opinion, that both potash at.d soda are of a metallic na- 

 ture is mentioned, if not directly, by implication. His 



words 



