Nairn & blunt voltic pistol, c 1780
A voltaic pistol made by nairne & blunt. 1778-1793 it has a mahogany stock and brass barrel with a stop-cocks. A brass plunger terminating in a disk slides into the mouth of the barrel. An oval indentation in the barrel indicates the position of the ball (now missing) of the electrode forming the spark gap inside the barrel.
The pistol was partly filled with hydrogen by means of a rubber bag (now missing). 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.
In 1776, alessandro volta began a series of experiments in which he used an electric spark to ignite methane (which he observed and collected in swamps) and detonate a mixture of hydrogen and air. Experiments with the electric pistol led to the invention of the hydrogen lamp and eudiometer.
Museum galileoin florance has also a nairn & blunt voltic pistol in there collection. Length 40 cm