470 Scientific Intelligence, [June, 



Article XIII. 



SCIENTIFIC INTELLIGENCE, AND NOTICES OF SUBJECTS 

 CONNECTED WITH SCIENCE. 



I. Action of Phosphorus and Water. 



It is well known that when phosphorus is kept in water, the sticks, 

 although at first transparent, are covered with a white opaque crust, 

 which eventually becomes of a reddish-yellow colour. 



Wishing to determine the nature of this change and the circum- 

 stances by which it is accelerated or retarded, I placed translucent 

 sticks of phosphorus in two vials nearly filled with distilled water. One 

 of the vials was exposed to day-light, and occasionally to the direct 

 rays of the sun. In a few hours, that side of the cylinder of phospho- 

 rus which was exposed to the light became opaque, and the water 

 acquired a peculiar smell. On putting litmus paper into the water, it 

 became of a red colour, indicating the presence of an acid, and which 

 was probably the phosphorous acid, or a mixture of that and the phos- 

 phoric : this I did not determine. I now added some of the water to 

 solution of nitrate of silver, and another portion to solution of proto- 

 nitrate of mercury ; in both cases, a dark-coloured precipitate was 

 formed, which is a well-known characteristic of the presence of phos- 

 phuretted hydrogen. By exposure to air, the solution loses its power 

 of giving a dark-coloured precipitate with silver and mercury, owing 

 partly to the evaporation of the phosphuretted hydrogen, and proba- 

 bly more to its conversion into phosphoric acid and water by absorbing 

 oxygen. After nearly a month had elapsed, I examined the pieces of 

 phosphorus which had been excluded from the action of the light; the 

 water in which they had been immersed was slightly acid, and gave indi- 

 cations of the presence of phosphuretted hydrogen in a slight degree; 

 the action, however, which had taken place was so trifling that the 

 transparency of the phosphorus was scarcely at all diminished. 



From this statement, it is evident, that phosphorus has the power of 

 decomposing water ; that oxide of phosphorus is first formed, and 

 eventually phosphorous or phosphoric acid ; and that the hydrogen of 

 the water forms phosphuretted hydrogen, with a portion of the phos- 

 phorus ; and, lastly, that these effects are much accelerated by the 

 action of light. — Edit. 



II. Phosphate af Uranium. 



In the Annals for January last, I gave an analysis of the green ura- 

 nite from Cornwall, and I stated my reasons for supposing that the 

 ura»ite from Autun, which has the same crystalline form as the 

 Cornish, was also a phosphate of uranium. Mr. Heuland having had 

 the kindness to present me with some of the French uranite, I subjected 

 it to examination, and found, as I had supposed, that it is a phosphate. 

 Joseph Carne, Esq. of Riviere, has also been so good as to supply 

 me with a new variety of the uranite from Cornwall ; this, instead of 

 being crystallized in square plates, and of a green colour, is composed 

 of fibres radiating from a centre ; this I also submitted to examination, 

 and found it to be similar to the specimens above alluded to — Edit. 



