...actinism; which affect terrestrial electricity and magnetism ; and which, as Sir John Herschel says, "are the ultimate source of almost every motion which takes place on the surface of the earth." At first glance, it may seem strange to try to make any comparison between light and gravity, but the...

...ultimate source of almost every motion which takes place upon the surface of the Earth. By its heal are produced all winds, and those disturbances in...electric equilibrium of the atmosphere which give nse to the phenomena of terrestrial magnetism. By their vivifying action vegetables are elaborated...