This telemeter was one of the first that was tried in our military ports, and gave therein most satisfactory results. The maneuver of the winch, however, requires a certain amount of stress, and in order that the sending of the currents shall be regular, the operator must turn it very uniformly. This is a slight difficulty that has led to the use of piles, instead of the magneto-electric machine, in the apparatus employed in France. With such substitution there is need of nothing more than a movable contact that requires no exertion, and that may be guided by the telescope itself.--_La Lumière Electrique_. * * * * * PHYSICS WITHOUT APPARATUS. _Experiment in Static Electricity_.--Take a pipe--a common clay one costing one cent--and balance it carefully on the edge of a goblet, so that it will oscillate freely at the least touch, like the beam of a scales. This being done, say to your audience: "Here is a pipe placed on the edge of a goblet; now the question is to make it fall without touching it, without blowing against it, without touching the glass, without agitating the air with a fan, and without moving the supporting table" [Illustration: CLAY PIPE ATTRACTED BY AN ELECTRIFIED GOBLET.] The problem thus proposed may be solved by means of electricity. Take a goblet like the one that supports the pipe, and rub it briskly against your coat sleeve, so as to electrify the glass through friction. Having done this, bring the goblet to within about a centimeter of the pipe stem. The latter will then be seen to be strongly attracted, and will follow the glass around and finally fall from its support. This curious experiment is a pretty variation of the electric pendulum; and it shows that pipe-clay--a very bad conductor of electricity--favors very well the attraction of an electrified body. Tumblers or goblets are to be found in every house, and a clay pipe is easily procured anywhere. So it would be difficult to produce manifestations of electricity more easily and at less expense than by the means here described.--_La Nature_. * * * * * THE CASCADE BATTERY. [Footnote: Lately read before the Society of Telegraph Engineers and Electricians.] By F. HIGGINS. The battery which I have brought here to-night to introduce to your notice is of the circulating kind, in which the alimentary fluid employed passes from cell to cell by gravitation, and maintains the action of the battery as long as it continues to flow. It cannot, of course, compare with such abundant sources of electricity as dynamo-electric machines driven by steam power, but for purposes in which a current of somewhat greater volume and constancy than that furnished by the ordinary voltaic batteries is required, it will, I believe, be found in some cases useful. A single fluid is employed, and each cell is provided with an overflow spout.