Frog battery

A good supply of live frogs was kept to hand by the researcher ready to have their legs prepared for the galvanoscope.

They were small, easily handled, the legs were especially sensitive to electric current, and they carried on responding longer than other animal candidates for this role.

Alessandro Volta's theory was proved correct when he succeeded in constructing the voltaic pile without the use of any animal material.

Because Valli found himself on the wrong side in this dispute, and refused to change his opinion despite the evidence, his work has become a bit of a backwater and his frog battery is little known and poorly documented.

[7] The first well-known frog battery was constructed by Carlo Matteucci which was described in a paper presented to the Royal Society in 1845 by Michael Faraday on his behalf.

It later also appeared in the popular medical student physics textbook Elements of Natural Philosophy by Golding Bird.

Matteucci aimed with this apparatus to address Volta's criticism of Nobili by constructing a circuit, as far as possible, entirely out of biological material and hence prove the existence of animal electricity.

Matteucci also studied the effects vacuum, various gases, and poisons had on the frog battery, concluding that in many cases its operation was not affected even when the substance would be toxic or lethal to the living animal.

A frog galvanoscope connected between the ox's tongue and ear showed a reaction when the circuit was completed through the experimenter's own body.