28 Improvements in Physical Science (Jan, 
a long paper by Bidault-de-Villiers in the Annales de Chimie (vol. 
xciii. p. 32) to prove that Scheele did not consider chlorine as a 
simple substance. The proof is most extraordinary. Scheele’s 
opinion was not adopted by chemists in general, not even by Davy 
himself; therefore Scheele did not maintain it. The very name, 
dephlogisticated muriatic acid, given to chlorine by Scheele, shows 
- us what his opinion was. Phlogiston in Scheele’s opinion, as every 
body knows, was hydrogen gas. If, therefore, chlorine was mu- 
riatic acid deprived of hydrogen, it is obvious that he must have 
considered muriatic acid as a compound of chlorine and hydrogen ; 
and accordingly this opinion was-maintained by Kirwan in his essay 
on phiogiston, on the authority of Scheele. Scheele says, in his 
essay on manganese, ‘‘ muriatic acid deprived of phlogiston, which 
is one of its constituent parts.” (L’acide muriatique depouillé du 
phlogistique qui est une de ses parties constituantes.)* 1 cannot 
conceive any thing more explicit than this, 
There can be no doubt that it was the experiments of Gay-Lussae 
and Thenard, published in their Recherches Physico-Chimiques, 
that led Davy to form the new theory. So far their merit is con- 
spicuous, But as they did not adopt the new theory in that work, 
but argued against it, nothing can be more ridiculous than to claim 
it after it has been established by another. If Gay-Lussac always 
maintained it, as he informs us, but was prevented from publicly 
embracing it by the authority of Berthollet, we may pity his pusil- 
lanimity, but cannot on that account admit his claim as the first 
propagator of a theory, which he publicly opposed, As to M. 
Ampere, his posthumous claim cannot be maintained, as he pub- 
lished nothing whatever on the subject. 
Gay-Lussac has lately added an important.fact to what was pre- 
viously known of chlorine. He has shown that it combines with 
more than its weight of oxygen gas, and forms an acid, to which 
he has given the name of chloric acid. He has pointed out a method 
of obtaining this acid in a separate state, and has shown that it is a 
constituent of the salts called formerly hyper-oxymuriates, to which 
henceforth the name of chlorates must be given. Vauquelin has 
published an account of the properties of these salts. 
Sir Humphry Davy has lately discovered a new gaseous com- 
pound of chlorine and oxygen; which does not seem to possess 
acid properties. It is obtained by reducing chlorate of potash 
(hyper-crymuriate of potash) to a powder, making it into a solid 
paste with sulphuric acid, and exposing it in a small retort toa heat 
not so high as 212°. A gas is obtained, which is the substance in 
question. It has a much more intense greenish yellow colour than 
chlorine; does not act upon mercury; but is rapidly absorbed by 
water. The taste of it is astringent, and it is very corrosive. When 
phosphorus is introduced into it an explosion takes place, and the 
* Memoires de Chymie de M. C. W. Scheele, i. p. 69. I quote the French 
translation, that the French chemists may consult the passage, theugh this deprives 
me of Kirwan’s notes, 
