Proceedings of the Royal Society of London, Vol. 81

Excerpt from Proceedings of the Royal Society of London, Vol. 81: Series A, Containing Papers of a Mathematical and Physical Character If i is comparatively feeble, and therefore 8 small compared with R0, this equation makes proportional to and since 72. Is not very different from 1 for red light, the change of resistance is roughly proportional to the fourth root of the intensity. A peculiarity of my seleno-aluminium bridges which must be mentioned is this: after the bridge has been in use for a considerable time (perhaps some months) its resistance for high voltages is extremely unsteady. Thus, a bridge which had been much used had a perfectly steady behaviour with 2 volts, but with 6 volts the spot on the scale moved with great suddenness over large distances, the bridge being all the time in the dark. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.