Like many of his contemporaries, Galvani was drawn by the fascinating behaviour of the new force of nature to carry on electrical experiments as a hobby alongside his professional work, anatomical research. For his experiments he used the room where his anatomical specimens were set out. So it happened that his electrical machine stood near some frogs' legs, prepared for dissection. By a further coincidence his assistant, while playing with the machine, released a few sparks just when some of the specimens were in such contact with the surface beneath them that they were bound to react to the sudden alteration of the electric field round the machine caused by its discharge. At each spark the frogs' legs twitched. What Galvani saw with his own eyes seemed to be no less than the union of two phenomena, one observed by Franklin in the heights of the atmosphere, the other by Walsh in the depths of the sea. Galvani, as he himself describes, proceeded with immense enthusiasm to investigate systematically what accident had thus put into his hands.2 He wanted first to see whether changes occurring naturally in the electrical condition of the atmosphere would call forth the same reaction in his specimens. For this purpose he fastened one end of an iron wire to a point high up outside his house; the lower end he connected with the nervous substance of a limb from one of his specimens, and to the foot of this he attached a second wire whose other end he submerged in a well. The specimen itself was either enclosed in a glass flask in order to insulate it, or simply left lying on a table near the well. And all this he did whenever a thunderstorm was threatening. As he himself reported: 'All took place as expected. Whenever the lightning flashed, all the muscles simultaneously came into repeated and violent twitchings, so that the movements of the muscles, like the flash of the lightning, always preceded the thunder, and thus, as it were, heralded its coming.' We can have some idea of what went on in Galvani's mind during these experiments if we picture vividly to ourselves the animal limbs twitching about every time the lightning flashed, as if a revitalizing force of will had suddenly taken possession of them.