ABSOLUTE QUANTITY OP ELECTRICITY IN MATTER. 119 



in full action (371.)« This quantity, though sufficient if passed at once through the 

 head of a rat or a cat to have killed it, as by a flash of lightning, was evolved by 

 the mutual action of so small a portion of the zinc wire and water in contact with it, 

 that the loss of weight sustained by either would be inappreciable by our most deli- 

 cate instruments ; and as to the water which could be decomposed by that current, it 

 must have been insensible in quantity, for no trace of hydrogen appeared upon the 

 surface of the platina during those three seconds. 



861. What an enormous quantity of electricity, therefore, is required for the decom- 

 position of a single grain of water ! We have already seen that it must be in quantity 

 sufficient to sustain a platina wire -^-^ of an inch in thickness, red hot, in contact with 

 the air for three minutes and three quarters (853.), a quantity which is almost infi- 

 nitely greater than that which could be evolved by the little standard voltaic arrange- 

 ment to which I have just referred (860. 371.)- I have endeavoured to make a com- 

 parison by the loss of weight of such a wire in a given time in such an acid, according 

 to a principle and experiment to be almost immediately described (862.) ; but the 

 proportion is so high, that I am almost afraid to mention it. It would appear that 

 800,000 such charges of the Leyden battery as I have referred to above, would be 

 necessary to supply electricity sufficient to decompose a single grain of water; or, if I 

 am right, to equal the quantity of electricity which is naturally associated with the 

 elements of that grain of water, endowing them with their mutual chemical affinity. 



862. In further proof of this high electric condition of the particles of matter, and 

 the identity as to quantity, of that belonging to them with that necessary for their 

 separation, I will describe an experiment of great simplicity but extreme beauty, 

 when viewed in relation to the evolution of an electric current and its decomposing 

 powers. 



863. A dilute sulphuric acid, made by adding about one part by measure of oil of 

 vitriol to thirty parts of water, will act energetically upon a piece of plate zinc in its 

 ordinary and simple state ; but, as Mr. Sturgeon has shown*, not at all, or scarcely so, 

 if the surface of the metal has in the first instance been amalgamated ; yet the amal- 

 gamated zinc will act powerfully with platina as an electromotor, hydrogen being 

 evolved on the surface of the latter metal, as the zinc is oxidized and dissolved. The 

 amalgamation is best effected by sprinkling a few drops of mercury upon the surface 

 of the zinc, the latter being moistened with the dilute acid, and rubbing with the 

 fingers so as to extend the liquid metal over the whole of the surface. Any mercury 

 in excess forming liquid drops upon the zinc, should be wiped off-f-. 



864. Two plates of zinc thus amalgamated were dried and accurately weighed ; one, 

 which we will call A, weighed 1631 grains ; the other, to be called B, weighed 1483 



* Recent Experimental Researches, &c., 1830, p. 74, &c. 



t The experiment may be made with pure zinc, which, as chemists well know, is but slightly acted upon by 

 dilute sulphuric acid in comparison with ordinary zinc, which during the action is subject to an infinity of 

 Toltaic actions. See Db la Rive on this subject, Bibliotheque Universelle, 1830, p. 391. 



