In 1776, Alessandro Volta began conducting a series of experiments with a singular instrument that he described as an "electrical-phlogopneumatic pistol." The experiment consisted in using an electric spark to explode methane or a mixture of hydrogen and common air inside the device. The detonation expelled the plunger from the mouth of the barrel.

In the late eighteenth century, the English instrument-makers Edward Nairne and Thomas Blunt produced an elegant model of the pistol, composed of a mahogany stock and a brass barrel with two stop-cocks. An oval indentation in the barrel indicates the position of the ball (missing) of the electrode forming the spark-gap inside the barrel.

The pistol was partly filled with hydrogen from a rubber bladder. The gas was detonated by a spark from a Leyden jar. The explosive force of the gas was measured by the movement of the plunger.

Experiments with the electric pistol remained in vogue largely as scientific curiosities, but they did pave the way for the invention of the hydrogen lamp and the eudiometer.

While conducting experiments on the Voltaic pistol with his students in Volterra, Eugenio Barsanti had an intuition that led him to develop the first model of the internal-combustion engine. His design applied the principle of the conversion of the explosive energy of a gas into mechanical work.