Page:Experimental researches in electricity.djvu/290

264 contact theory, balanced (848). Then fig. 68 may represent the circle of platinum, lead, and solution of sulphuret, which does produce a current, and, as I have assumed, with a resulting force of 11→. This in a few minutes becomes quiescent, i.e. the current ceases, and fig. 69 may represent this new case according to the contact theory. Now is it at all likely that

by the intervention of sulphuret of lead at the contact c, fig. 68, and the production of two contacts d and e, fig. 69, such an enormous change of the contact force suffering alteration should be made as from 10 to 21? the intervention of the same sulphuret either at a or b (822, 828) being able to do nothing of the kind, for the sum of the force of the two new contacts is in that case exactly equal to the force of the contact which they replace, as is proved by such interposition making no change in the effects of the circle (855, 828). If therefore the intervention of this body between lead and platinum at a, or

between solution of sulphuret of potassium and platinum at b (fig. 68) causes no change, these cases including its contact with both lead and the solution of sulphuret, is it at all probable that its intervention between these two bodies at c should make a difference equal to double the amount of force previously existing, or indeed any difference at all?

878. Such an alteration as this in the sum assigned as the amount of the forces belonging to the sulphuret of lead by virtue of its two places of contact, is equivalent I think to saying that it partakes of the anomalous character already supposed