VOL. XC.] PHILOSOPHICAL TRANSACTIONS. 04g 



acid gas, its bulk is enlarged, and a permanent gas is produced, which is evidently 

 a mixture of oxygenous and hydrogenous gases ; for when an electrical spark is 

 passed through the gas that remains after the absorption of the carbonic acid by 

 caustic alkali, it immediately explodes. These results even take place on electrify- 

 ing carbonic acid from marble, previously calcined in a low red-heat, to expel its 

 water, and then distilled in an earthen retort.* 



XI. On a New Fulminating Mercury. By Edw. Howard, Esq. F. R. S. p. 204. 



§ 1. The mercurial preparations which fulminate, when mixed with sulphur, 

 and gradually exposed to a gentle heat, are well known to chemists: they were 

 discovered, and have been fully described, by Mr. Bayen.-f- MM. Brugnatelli and 

 Van Mons have also produced fulminations by concussion, as well with nitrate of 

 mercury and phosphorus, as with phosphorus and most other nitrates. J Cinnabar 

 also is among the substances which, according to MM. Fourcroy and Vauquelin, 

 detonate by concussion with oxymuriate of pot-ash. § Mr. Ameilon had, accord- 

 ing to Mr. Berthollet, observed, that the precipitate obtained from nitrate of mer- 

 cury by oxalic acid, fuses with a hissing noise || 



§ 2. But mercury, and most if not all its oxides, may, by treatment with nitric 

 acid and alcohol, be converted into a whitish crystallized powder, possessing all the 

 inflammable properties of gunpowder, as well as many peculiar to itself. — I was 

 led to this discovery, by a late assertion, that hydrogen is the basis of the muriatic 

 acid : it induced me to attempt to combine different substances with hydrogen and 

 oxygen. With this view, I mixed such substances with alcohol and nitric acid, as 

 I thought, by pre-disposing affinity, favour as well as attract an aeid combination, 

 of the hydrogen of the one, and the oxygen of the other. The pure red oxide 

 of mercury appeared not unfit for this purpose; it was therefore intermixed with 

 alcohol, and nitric acid was affused on both. The acid did not act on the alcohol, 

 so immediately as when these fluids are alone mixed together, but first gradually 

 dissolved the oxide: however, after some minutes had elapsed, a smell of ether was 

 perceptible, and a white dense smoke, much resembling that from the liquor 

 fumans of Libavius, was emitted with ebullition. The mixture then threw down 

 a dark-ooloured precipitate, which by degrees became nearly white. This precipi- 

 tate I separated by filtration; and observing it to be crystallized in small acicular 

 crystals, of a saline taste, and also finding a part of the mercury volatilized in the 

 white fumes, I must acknowledge I was not altogether without hopes that muriatic 



* Messrs. Landriani and Van Marum (Annates de Chimie, torn. 2, p. 270), obtained only hydroge- 

 nous gas, by electrifying the carbonic acid gas. But the conductor of their apparatus was an iron one ; 

 which metal would combine with the oxygen of the water, and prevent it from appearing in a gaseous 

 state. In my experiments, the conductors were of platina. — Orig. 



+ Opuscules Chimique de Bayen, torn. 1, p. 346", and note in p. 344. % Annales de Chimie, 

 torn. 27, p. 74 and 79. § Ibid. torn. 21, p. 238. || This fact has been misrepresented, in the 

 introduction to a work entitled The chemical Principles of the metallic Arts, by W. Richardson, sur- 

 geon, f a.s., Sc. (p. 57). — Orig. 



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