74 Mr. Binks on the Laws of Action of Voltaic Electricity, 



By which it is made apparent that (compared with equal 

 plates) the effectiveness of any simple voltaic circle is increased 

 about 4^ times, by having the surface of copper 16 times 

 greater than the zinc. 



But these results may not follow from the operation of an 

 invariable law, but of one peculiar to the prevailing condi- 

 tions of the arrangements herein employed ; as the activity of 

 its action may evolve as much hydrogen as needs so large a 

 surface to permit its formation with the greatest facility. But 

 let the activity of the generating agents be lessened, and will it 

 then need a surface equal to lb*, comparatively? to induce the 

 greatest effect? Now this rapidity of action may be lessened 

 by either removing the elementary plates further apart, or by 

 more largely diluting the exciting acid. And to determine the 

 influence of such changes, first, the plates were separated from 

 the distance of one inch to that of two inches, and the experi- 

 ments, with coppers of various surfaces, repeated, when, al- 

 though less zinc was expended in the aggregate during an 

 equal time, yet the greatest loss in any given period occurred 

 when the copper was 16 times larger than the zinc. 



The plates being restored to their usual distances from one 

 another, the experiments were repeated twice, with acid solu- 

 tions, formed, first, by the mixture of 2^ parts acid and 100 

 water, and, secondly, of 9 parts acid and 100 water, when 

 the results were so nearly the same as those registered in the 

 above table, as to indicate, without doubt, the operation in 

 each instance of the same law, and to make it unquestionable 

 that it was general, within at least the range of those circum- 

 stances here brought into operation. For though, in the one 

 case, the quantity of action was less and in the other more than 

 in the standard tables, yet the maximum effect, in the respect- 

 ive sets of trials, was always exhibited when the copper was 16 

 times greater than the zinc. 



An important point of inquiry now presents itself to be de- 

 cided, namely, whether it is by the extension of surface merely 

 that this advantage is gained, or whether it be due to the 

 greater mass of conducting copper thus brought into action, 

 or to the united influence of both. Experiments were made 

 to determine this point, from which this one may be selected : 



An amalgamated zinc plate, measuring 4- square inches, was 

 employed in the first instance, along with a sheet of thin cop- 

 per, weighing a few ounces, and having a surface of 16 square 

 inches, when the result in zinc lost was 6~ J T) grains. Then the 

 same zinc plate was connected with a solid prism of copper, of 

 the same external dimensions as the sheet just used, but weigh- 

 ing about two pounds, when the zinc lost, during an equal time, 



