If a tumbler, electrified in this way, be inverted over pith balls, instead of brass-filings, the balls will leap with surprising velocity up the sides of it. _The luminous Discharging-rod._ Provide a glass tube in the shape of a common discharging-rod, about ten inches in length, and let the bore of the tube be nearly the eighth of an inch in diameter; upon one end fasten with cement, or otherwise, a brass knob, so as to be perfectly air tight. Now expel the air from the tube, by heat or the air pump, and then fix another knob upon the open end, in a way similar to the former. If the instrument be used as the common discharging-rod, it will be found to answer its purposes equally well; while at the same time all the inner surface of the tube, during the discharge of a jar with it, is beautifully luminous. Mr. Nairne also contrived a luminous discharging-rod. It consisted of an arched glass tube, with a metallic ball at each end, and a communication from one ball to the other was made by a brass chain, which passed through the bore of the tube.—In the discharge of a jar with it, small sparks are seen between the links of the chain within the tube.—Both these dischargers should have handles fastened to them. _To decompose Water by Electricity._ Let a glass tube, having a small bore, be filled with water; then close each end of the tube with a piece of cork, and let two wires pass through the corks, so that their extremities may come pretty near each other within the tube. If sparks of electricity be made to pass between the ends of the wires, within the tube, the water will be converted into oxygen and hydrogen gases. If this process be continued till the extremities of the wires become immersed in the two gases, they will explode and again form water. _The Electrified Fountain._ Insulate a small fountain made of metal, (one on the construction of _Hiero’s_ will be found most convenient,) and connect it with the prime-conductor—put it in operation—the jet will be undivided, except at the top—now turn the cylinder, and you will immediately perceive the jet divided much lower than at first; the drops, which before fell nearly perpendicularly, will now be thrown off in elliptical lines, and attracted by any conductor brought near them. A small Leyden phial may be charged at the top of the jet, which will present the curious spectacle of fire coming out of water. EPITOME OF ELECTRICITY. DIVISION III. CHAP. I. _Introductory Observations to the theory of Electricity._