Eudiometer truly pioneered by Count Alessandro Volta (1745–1827), an Italian physicist who is well known for his contributions to the electric battery and electricity. Aside from its laboratory function, the eudiometer is also known for its part in the "Volta pistol". Volta invented this instrument in 1777 for the purpose of testing the "goodness" of air, analyzing the flammability of gases, or to demonstrate the chemical effects of electricity. Volta's Pistol had a long glass tube that was closed at the top, like a eudiometer. Two electrodes were fed through the tube and produced a spark gap inside the tube. Volta's
Electric potential one can therefore write where "V" is the scalar potential defined by the conservative field F. The electrostatic potential is simply the special case of this definition where A is time-invariant. On the other hand, for time-varying fields, unlike electrostatics. The SI derived unit of electric potential is the volt (in honor of Alessandro Volta), which is why a difference in electric potential between two points is known as voltage. Older units are rarely used today. Variants of the centimeter gram second system of units included a number of different units for electric potential, including the abvolt and the statvolt.