atmospheric electricity. For this purpose he took some frogs, skinned them, cut off their heads and fore paws, and attached them by copper hooks to the roof, under an iron gutter. He thought that if a thunder-shower came up and the atmosphere was full of electricity, then the electricity would be brought to the frogs through the copper wire, and they would begin to kick.
But though several thunder-showers came up, the frogs did not move. Galvani proceeded to take them down, and while he was doing so, he touched the leg of one of the frogs to the gutter and the leg kicked! Galvani then took the frogs and began to make the following experiment: he attached iron wire to the copper hook and then touched the frog's leg with the wire—the leg kicked.
Here Galvani came to the conclusion that all animals are alive only because they have electricity in them, and that electricity leaps from the brain into the flesh and thus animals move.
No one had at that time gone very thoroughly into the study of this matter, and as nothing was known about it, every one put faith in Galvani's explanation.
But about this time another scientist, Volta, began to experiment for himself, and proved conclusively that Galvani was mistaken. He tried touching the frogs, not as Galvani had done with a copper hook and an iron wire, but first with a copper hook and a copper wire—and then with an iron hook and an iron wire and the frogs did not stir. They moved only when Volta touched them with an iron wire attached to copper.
So Volta came to the conclusion that the electricity was not in the dead frog, but in the iron and copper. He continued to make his tests, and this was the result: As soon as he placed iron and copper together, electricity was produced, and the electricity caused the dead frogs to kick. Then Volta began to try how to make electricity in a different way from what had been done before. He tried putting together various metals like the iron and copper, and he reached the conclusion that only from the contact of such metals as silver, platinum, zinc, tin, iron, he could produce electric sparks.
