1822.] Decomposition of Metallic Salts b}/ the Magnet. 39 



gen and charcoal in proportions which remain to be determined," 

 but a modification of olefiant gas, constituted of the same 

 elements as that fluid, and in the same proportions, with this 

 only difference, that the compound atoms are tiiple instead of 

 double. May we not be permitted to infer from this, that there 

 is yet another and a simpler combination of carburetted hydrogen 

 undiscovered, in which one atom of each of the elements is 

 associated in the usual binary form ? 



Article IX. 



Observations on Mr. Murray^s Paper on the Decomposition of 

 Metallic Salts by the Magnet. 



(To the Editor of the Annals of Philosophy.) 



SIR, 



Mr. Murray's paper is contained in the last number of the 

 Philosophical Magazine, and the author prefaces his relation 

 with saying : " I shall here take leave to select a few of the 

 numerous experiments repeated in the course of my researches, 

 and it would, methinks, be difficult to summon any objection to 

 them." I beg leave to differ from Mr. Murray, and for reasons 

 which I shall now assign. 



Mr. Murray's first statement is, that '^ a solution of permu- 

 riate of mercury was by the magnet soon reduced into running 

 mercury, and the supernatant fluid was not affected by the albu- 

 men of the egg." 



I prepared a dilute solution of corrosive sublimate, and placed 

 a perfectly unmagnetic steel bar in the solution, " running mer- 

 cury " was immediately precipitated. Hence magnetism is not 

 requisite to the production of the effect, and consequently it is 

 worthy of Mr. Murray's consideration, whether " fine steel 

 filings " unmagnetized will not be as ** admirable an antidote to 

 corrosive sublimate " as those which are magnetized. I believe 

 their inefficacy will be equal. 



Mr. Murray says : " Nitromuriate of platinum was decom- 

 posed with a brisk effervescence, distinctly audible, and with a 

 visible spray between the eye and the light." I placed an 

 unmagnetic steel bar in a solution of nitromuriate of platina, and 

 the platina was precipitated with all the phenomena above 

 described by Mr. Murray. Consequently magnetism has no 

 share in producing the decomposition. 



*' Fine Dutch steel wire was selected," says Mr. Murray, '' and 

 proved to be non-magnetic. It was thrown into nitrate of silver 

 wliere it remained for 14 hours without being affected, part of 

 this was made the uniting wire between the north and south 



