Besides these experiments, which were made by a society of gentlemen, a variety of others were performed, from which nearly the same conclusions were deduced.—Two other facts, however, deserve notice. 1. When metallic leaves are deflagrated in carbonic-acid gas, the flame is weak: but when in oxygen gas, the communication between the upper and under plates of the pile is no sooner formed, than the metallic leaves are destroyed with one sudden flash. 2. When metals are subjected to Galvanism in an exhausted receiver, they emit light but are not oxydated. CHAP. VII. _Further Galvanic Experiments on Metals, and on other Substances._ It is hardly necessary to mention, that every experiment made by means of the Galvanic pile may be performed, with equal success, with the trough. The experiments related in this chapter may be effected by the pile, but they cannot be done with the same convenience as when troughs are used. The battery[19] employed in these experiments consisted of sixty pieces of silver, and a like number of zinc, each two and a quarter inches square. The shock produced by this trough, by means of two metallic conductors, was distinctly felt in the shoulders, and the contraction or spasm was so violent, as to render the operator unable to hold the conductors, when in contact with the plates by which the trough terminated each way.—A sensation resembling that produced by hot water, was at the same time felt in the wrists and fore-arm. A small steel wire, which was used for the conductor to form the communication, upon its contact with the plates, produced a vivid spark and bright scintillations.—When a piece of phosphorus was placed upon the end of this wire, and made a part of the circuit, it was instantly inflamed. Another battery of the same size being connected with the one above described, gun-powder was fired, and gold leaf deflagrated without any perceptible residuum—being probably volatilised by the heat occasioned by the experiment.