74 Mr Kemp on a New Kind of Galvanic Pile. 



state, without any diminution having taken place, for the zinc alone is acted 

 upon ; and when this is the case, the former process has only to be repeated. 



The amalgam, when once made, may be kept, for any length of time, in 

 vessels excluded from the action of the atmosphere, and may be poured from 

 thence in one moment, when wanted, into cups of the requisite size. 



Without at present entering into detail regarding the laws which govern 

 the action of this pile, farther than that they appear to be very different from 

 any other, which seems to depend upon the positive plate being liquid, I 

 shall merely notice the following experiments, which were performed by 

 means of a pile, consisting of twelve cups one inch and a-half in diameter. 



Having poured into each of them as much of the amalgam of mercury and 

 zinc as covered the bottom, and added the muriatic acid and water, (the pro- 

 portions being ten parts of water, one of acid, and two of the muriate of soda, 

 these may, however, be varied), I placed them above each other, as shewn 

 in Fig. 4. ; the copper-plate of the one being in contact with the acid of that 

 immediately under, through the medium of the wire. 



I may here notice an important fact connected with this pile, — that in this 

 state the cups may remain for any length of time ready for experimenting with, 

 without almost any decrease of galvanic energy. This certainly is a decided 

 superiority over any other form of galvanic apparatus, for it is well known, 

 that it is only at the first instant, after being charged, ihat batteries produce 

 their full effect ; at every succeeding instant it becomes less ; and in a short 

 time it entirely ceases. This seems to depend upon the particles of zinc, 

 which, having perfect freedom of motion in the mercury, are attracted by the 

 copper-plate with which'jthey are in contact, through the medium of the wire ; 

 and, by this means, the mercury is alone exposed to the acid, which has no ac- 

 tion upon it. But, upon the destruction of the electrical tension, by complet- 

 ing the circuit, the particles of zinc are no longer attracted by the copper- 

 plate, and, having perfect freedom of motion in the mercury, rise to the sur-^ 

 face, are acted upon by the acid, and have again a tendency to restore the 

 pile to its former state of tension. It will thus be perceived, that the action 

 going on in the pile, and, consequently, the quantity of electricity evolved, 

 is in exact proportion to the conducting power of the substance employed to 

 complete the circuit ; and this fact is still farther illustrated by the experi- 

 ments. 



In the first experiment, I completed the circuit by two small platina wires ; 

 and immersing them in a glass containing pure water, a slow action imme- 

 diately took place in the body of the pile, and the water was decomposed, the 

 hydrogen appearing at the negative, and the oxygen at the positive wire. I 

 then added to the water a quantity of sulphate of soda, to increase its con- 

 ducting power. A more rapid action immediately took place in the pile, and a 

 proportionately increased decomposition was effected in the solution. 



When a leaf of silver is employed to complete the circuit, by means of a 

 wire and plate of zinc, a combustion of a continuous nature takes place, and 

 also a more rapid action goes on in the pile. 



The combustion of the metals by this pile seems to be totally different 

 from that produced by solid batteries ; for the more the zinc plate is brought 

 into contact with the leaf of silver, the greater is the generation of electricity 



