Experiments on carhnated Hydrogen Gat, ■ jxc 



this confequence would really follow, I expofed a portion of the gas for feveral days before 

 electrization to dry cauftic alkali. On attempting its expanfion, 1 found that it could 

 not be carried beyond one fixth the original bulk of the gas. By 160 very ftrong ex- 

 plofions it attained this fmall degree of dilatation, but 80 more produced not the leaft 

 e&eSt; though the former number would have been amply fufficient to have dilated the gas 

 in its ordinary ftatc to more than twice its original volume. A drop or two of water being 

 admitted to this portion of gas, the expanfion went on as ufual ; and I may here obferve, that 

 when a little water gained admiflion into the tube along with the gas, in any experiment, 

 which often happened before I had acquired fufficient expertnefs in transferring the air from 

 Water to mercury, the dilatation went on with remarkable rapidity. 



Carbonic acid gas, according to the difcovery of M Monge *, undergoes, when fubmitted 

 to the eleflric (hock, a change fimilar to that efFeded on the carbonated hydrogen; and the 

 expanfion has been fhewn by MefTieurs Landriani, and Van Marum f, to be owuig to ihe 

 fame caufe, viz. the extrication of light inflammable air. The added gas, M. Montre ably 

 contends, cannot proceed from any other fourne than the water held aifolutionby all aenform 

 bodies, the oxygen of which he fuppofes to combine with the mercury. That the decom- 

 ponent of the water, however, in the experiments which I have defcribed, Is not a metallic 

 body, will appear highly probable, when we reflect that there is prefent in them a combuftible 

 fiibftance, viz. charcoal, which attrafls oxygen much more ftrongly than metals ; and the 

 following experiments evince, that the mercury by which- the air was confined had no fliarc 

 in producing the phenomena. 



Experiment C). A portion of carbonated hydrogenous gas was introduced into a glafs tube 

 clofed atone end, into which a piece of gold wire was infertedj that proje£led both within 

 and without the cavity of the tube. The open end of the tube was then clofed by a flopper 

 perforated alio with gold wire, fo that eled^rlc fhocks could be paiTed through the confined 

 air without the contaft of any metal that has the power of decompofing water. On open- 

 ing the tube with its mouth downwards under water, a quantity of air immediately rulhed 

 out. 



Experimfht 10. The dilatation of the gas was found to proceed very rapidly when (land- 

 ing oVer water, and expofed to the aftion of the ele£tric fluid, conveyed by gold con- 

 dudlors. 



We have only, therefore, in the two preceding experiments, one fubftance in contaft with, 

 the gas whici is capable of decompofing water, viz. charcoal. The union of this hody 

 with the oxygen of the water would be rendered palpable by the formation of carbonic 

 aci ; but Dr. Auftin did not obferve that any precipitation was occafionedin lime water by 

 agitating it with the eledlrified gas. On palling up fyrup of violets to the eiedrrified air, 

 with the expedtation of its indicating the volatile alkali, as in the experiments of Dr. Aultin, 

 no change of colour took place, though the teft was of unexcepcionable purity. On exa- 

 minmg, however, whether any alteration of bulk had been produced in the air by the con- 

 tact of this liquid, it appeared that of 709 meafureS' 100 had been abforbed. SufptCting 

 that the abforption was owing to' the^prefence of i;arbonic acid, t introduced fonie ILmc- 

 water to a volume of the expanded gas, amounting to 5^6 meafu/es, when they were im-- 

 mediately reduced to 512. The contra'dlion would probably have been ftill ludre remark- 



• Journal de Phyfique, xxix. 177. f Annales de Chimie, iU 473. 



able. 



