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as the copper can be curved in any way the experi-menter thinks proper, devices of any required formmay be obtained on the upper surface of the zinc.

I have the word Fabroni formed on the lower edgeof a slip of copper, by means of which I occasion-ally in my lectures, imprint the name of the authorof this first of electro-decompositions of water by adirect Galvanic association of metals.

As it is not my intention to enter very minutelyinto the theory of Galvanism, until the next and sub-sequent lectures, I shall, in this place, offer to yournotice only a few experiments from which Galvanic phenomena have been supposed to have an electricorigin.

I have already stated that, in the Franklineantheory of electricity, it is supposed that each indi-vidual kind of matter has a specific quantity of theelectric fluid naturally belonging to it, so that no twobodies of the same size, if of different kinds, containequal quantities ; which view of the natural distribu-tion of the electric fluid amongst terrestrial bodies,appears to be perfectly correct, at least under certaincircumstances. I shall, however, have to show you,as we proceed, that the distribution of electric matter,even in one individual body, may be, and more fre-quently than otherwise is, very different in differentparts of it; depending on its state of aggregation,crystallization, compactness, state of its surface withregard to polish, temperature, &c.; and if it can beshown that different parts of the surface of one andthe same piece of metal, which are attached to eachother by the best conducting union, are neverthelessin different electric conditions at one and the sametime, it is easy to imagine that two distinct kinds ofmatter may be in different electric conditions, evenwhen in close contact with each other.

The experiment of Lichtenberg, already explainedin my “ Lectures on Electricity,” shows this fact ina more striking and interesting manner than any withwhich I am acquainted ; and as it is one of high