Improvements in Science. 297 



passing chlorine through phosphuretted hydrogen. The 

 gas which remains after the separation of the sub-hydret of 

 phosphorus is asesqui-hydret consisting of 18*719 hydrogen 

 and 201*11 phosphorus or HU Ph. Leverrier considers 

 that the sub-hydret is formed by the light, and does not 

 exist in the inflammable gas ; because as analysis always 

 indicates an excess of phosphorus in the latter, we cannot 

 consider it a pure chemical compound, but rather a mix- 

 ture of sesqui-hydret (EDi Ph) with a compound containing 

 less hydrogen, which cannot be the subhydret (Hi Ph) 

 as this is solid. He conceives that it must be a compound 

 H Ph, which has not yet been isolated, corresponding to 

 hypo-phosphorus acid, and inflaming in the air. When ex- 

 posed to the action of light it is decomposed into Hi Ph 

 and HH Ph. and is, therefore, a compound possessing little 

 stability like nitric oxide to which it corresponds. He 

 estimates the quantity of sub-hydret at -£$, and the hydret 

 or H Ph at -jV of the weight of inflammable gas. The 

 gas prepared from phosphorus acid consists of "1872 hydro- 

 gen, and 1*966 phosphorus = HH Ph, and is, therefore, 

 the same as that produced by the action of light upon 

 inflammable gas. 



This is certainly a very simple view of the subject. 



Leverrier, like his countrymen on other subjects, seems 

 ignorant of what has been done before him to clear up the 

 anomalies in the combinations of phosphorus and hydrogen. 

 If he had made himself acquainted with the ingenious re- 

 searches of Mr. Graham, he would have discovered that 

 his theory does not agree with the experiments of Mr. 

 Graham, for the latter found that potassium and other 

 substances, in very minute quantity, destroyed the inflam- 

 mability. If, however, we suppose that Mr. Graham per- 

 formed his experiments under the influence of circumstances 

 calculated to produce the decompositions which Leverrier 

 has shewn to take place, then the anomalies are removed. 



The compounds of phosphorus and hydrogen, according 

 |o Leverrier, therefore, are 



1 Sub-hydret. H4 Ph Solid. 



2 Hydret . . H Ph A gas spontaneously inflammable 



in the air, which has not yet been 

 isolated ; decomposed by light. 



