278 Sir H. Davy on the Substances produced 



place; and it evidently depended upon the presence of hydro- 

 gen in the vapour of the atmosphere, or in the flame of the 

 spirit lamp, by which the experiment was made, and I found 

 muriate of silver decomposed, and silver produced under the 

 same circumstances. 



From the general tenor of the results that I have stated, it 

 appears reaspnable to conclude that there exists in the fluoric 

 compounds a peculiar substance, possessed of strong attractions 

 for metallic bodies and hydrogen, and which combined with 

 certain inflammable bodies forms peculiar acids, and which, in 

 consequence of its strong affinities and high decomposing agen- 

 cies, it will be very difficult to examine in a pure form, and, 

 for the sake of avoiding circumlocution, it may be denomi- 

 nated ^worm^, a name suggested to me by M. Ampere. 



From experiments that I have made on the composition of 

 the fluoric combinations, and which I shall soon have the 

 honour of communicating to the Society, it appears that the 

 number representing the definite proportion in which fluorine 

 combines, is less than half the number representing that in 

 which chlorine combines ; and hydrates in becoming fluates 

 lose weight, so that on the generally received idea of the 

 existence of a peculiar acid in the fluates, and of their being 

 compounds of oxides, with an acid containing oxygen, that 

 acid, according to the law of definite proportions, must con- 

 tain more oxygen in proportion to its quantity of inflammable 

 matter than water, which is highly improbable, and contrary 

 to all analogies. 



Dr. WoLLASTON has found, that the fluoric combinations 

 have very low powers of refracting light, and particularly the 

 pure fluoric acid ; so that the refracting powers of fluorine 



