COLLEGE LECTURES.

Globe, Volume XX, Issue 1429, 13 September 1878, Page 3

COLLEGE LECTURES.

Professor Bickerton last night delivered the fifth of his series of lectures on electricity. After briefly recapitulating the substance of the previous lectures, he said that the present lecture would treat of the applications of electricity. Por many purposes it would be well to consider electricity as'flowing water, a large number of cells might be compared to a great elevation. Water flowing through a long pipe would meet with great resistance, so too would electricity conveyed from a long distance. If the wires were thin, they would bo like small water pipes, therefore for the conveyance of a large volume of electricity the wires should be as short and as thick as possible. Ho explained that the spark was caused by the resistance offered by the air to the passage of the electricity. In the same way he explained the development of heat, illustrating his explanation by some very beautiful experiments with platinum wire, the electric light, and an iron file. The electric lamp consisted of an apparatus, which kept the two currents of electricity. To develop heat it was necessary to convey the electricity, by means of the best conductor, to the spot where the heat was required, and then to connect it with non-conducting materials. He next explained chemical decomposition as produced by electricity. This part of the lecture was illustrated by the exhibition of the Voltameter, decomposition of water, and the formation of a “ lead tree.” The electric magnet was then explained and its great power exemplified by several experiments. The next portion of the lecture was devoted to the practical application of electricity for lighting purposes, the lecturer lighting a number of gas jets at once, also the sunlight in the roof of the theatre. An illustration of the manner in which torpedoes are exploded was given in the igniting of a quantity of gunpowder. The lecture concluded with a description of Morse’s magnetic telegraph, and a promise that next week the subject would be induced electricity, with some account of the most interesting modern discoveries. The lecture was listened to with great apparent interest, and frequently elicited applause.