Professor Volta’s first contrivance for manifesting Galvanism in a more vigorous manner than had hitherto been done, was what he called a _couronne de tasses_. This consisted of tumblers of glass, half filled with water, or salt and water. These glasses or tumblers, were so placed that a metallic arc, in form of a C, could be fixed with one leg in one glass, and the other in the next glass. On one end of each arc, was fastened a small plate of silver or copper, and on the other end, a similar plate of zinc or tin. These plates were immersed in the fluid contained in the tumblers.—Thus in the water of every glass there was a plate of silver or copper, and another plate of zinc or tin. The metallic arcs were formed of any good conductor. When thirty or forty of these glasses were prepared, the experimenter put one of his hands into the fluid contained in the first glass, and the other hand into that in the last: when this was done a shock, something like the electrical one, was experienced, and would recur as often as the circuit was interrupted and completed. Mr. Volta remarks, that _alkaline solutions_ are used to the most advantage when one of the metals is tin and the other silver or copper; but that where zinc is substituted for tin, salt water is preferable. After this discovery, Volta invented a much more convenient instrument, which, besides other advantages over the former, was more powerful and less expensive. The instrument is called the _Galvanic pile_, and very often the _Voltaic pile_, from its inventor. It is made in the following manner—Take a number of circular plates of copper, or silver and an equal number of tin or zinc of the same dimensions. Next provide a like number of round pieces of paste-board, leather, or any other substance capable of retaining moisture for a considerable time. This leather, cloth or other substance, must be rather smaller than the metal plates and, when used, well moistened with salt and water. Now form a pile, by laying alternately the zinc over the silver, and, the cloth or other moistened substance, over the zinc; and so on successively.—By thus continuing the series to forty or fifty plates, a Galvanic pile will be constructed. If the pile is intended to be of any considerable height, it ought to be secured by pillars of varnished baked wood; or strong glass tubes. To get the shock, one hand must touch the bottom, and the other the top plate.—The hands should be wet, as the cuticle or external part of the skin is a bad conductor. Shocks may be received by applying the hands in this manner, as long as the leather, or other substance interposed between the zinc and silver, continues moist; but as soon as it becomes dry the operation closes.