\Gun"pow`der\, n. (Chem.)
A black, granular, explosive substance, consisting of an
intimate mechanical mixture of niter, charcoal, and sulphur.
It is used in gunnery and blasting.
Note: Gunpowder consists of from 70 to 80 per cent of niter,
      with 10 to 15 per cent of each of the other
      ingredients. Its explosive energy is due to the fact
      that it contains the necessary amount of oxygen for its
      own combustion, and liberates gases (chiefly nitrogen
      and carbon dioxide), which occupy a thousand or fifteen
      hundred times more space than the powder which
      generated them.
{Gunpowder pile driver}, a pile driver, the hammer of which
   is thrown up by the explosion of gunpowder.
{Gunpowder plot} (Eng. Hist.), a plot to destroy the King,
   Lords, and Commons, in revenge for the penal laws against
   Catholics. As Guy Fawkes, the agent of the conspirators,
   was about to fire the mine, which was placed under the
   House of Lords, he was seized, Nov. 5, 1605. Hence, Nov. 5
   is known in England as {Guy Fawkes Day}.
{Gunpowder tea}, a species of fine green tea, each leaf of
   which is rolled into a small ball or pellet.