648 PHILOSOPHICAL TRANSACTIONS. [ANNO 1800. 



after mature deliberation, appeared to me most to promise success; and the expe- 

 riments were attended with a degree of labour, which can only be estimated by 

 those who have been engaged in similar pursuits ; not one-third of those which 

 were really made having been described, in the foregoing account of them. It 

 may spare therefore to others a fruitless application of time and trouble, to be 

 made acquainted with what I have done ; and the collateral facts, which have 

 presented themselves in the inquiry, are perhaps not without curiosity or value. 



From the result of these experiments, I apprehend all hope must be relin- 

 quished, of effecting the decomposition of the muriatic acid, in the way of single 

 elective affinity. They furnish also a strong probability, that the basis of the 

 muriatic acid is some unknown body; for, no combustible substance with which 

 we are acquainted, can retain oxygen, when submitted, in contact with charcoal, 

 to the action of electricity, or of a high temperature. The analysis of this acid 

 must, in future, be attempted with the aid of complicated affinities. Thus, in the 

 masterly experiment of Mr.Tennant, phosphorus, which attracts oxygen less strongly 

 than charcoal, by the intermediation of lime decomposes the carbonic acid. Yet, led 

 by the analogy of this fact, its discoverer found that a similar artifice did not suc- 

 ceed in decomposing the muriatic acid. " As vital air," he observes, " is attracted 

 by a compound of phosphorus and calcareous earth, more powerfully than by char- 

 coal, I was desirous of trying their efficacy on those acids which may from analogy 

 be supposed to contain vital air, but which are not affected by the application of 

 charcoal. With this intention, I made phosphorus pass through a compound of 

 marine acid and calcareous earth, and also of fluor acid and calcareous earth, but 

 without producing in either of them any alteration. Since the strong attraction 

 which these acids have for calcareous earth tends to prevent their decomposition, it 

 might be thought, that in this manner they were not more disposed to part with 

 vital air than by the attraction of charcoal : but this however does not appear to be 

 the fact. I have found, that phosphorus cannot be obtained by passing marine 

 acid through a compound of bones and charcoal when red-hot. The attraction 

 therefore of phosphorus and lime for vital air, exceeds the attraction of charcoal, 

 by a greater force than that arising from the attraction of marine acid for lime."* 



By means similar to those employed in attempting the analysis of the muriatic 

 acid, I tried to effect that of the fluoric acid. When electrified alone, in a glass 

 tube coated internally with wax, it sustained a diminution of bulk, and there 

 remained a portion of hydrogenous gas. But neither in this mode, nor by sub- 

 mitting it, mixed with carbonated hydrogenous gas, to the action of electricity, 

 was any progress made towards its analysis. These experiments however render it 

 probable, that the fluoric acid, like the muriatic, is susceptible of still further 

 oxygenation, in which state it becomes capable of acting on mercury. The car- 

 bonic acid, on the contrary, appears not to admit of different degrees of oxygena- 

 tion. When the electric shock has been repeatedly passed through a portion of this 



* Phil. Trans., vol.81, p. 184.— Orig. 



