Bicarburetted hydrogen is the principal constituent of the gas burned
in the streets: it is procured from coal, and the process may readily
be performed on a small scale. Put about two ounces of pounded coal
into an earthen retort, and fix a glass tube into the neck, terminating
in an aperture of one-fifth of an inch in diameter; heat the retort
red-hot, and apply the flame of a taper to the orifice of the tube,
when the gas will burn with a bright white light, very different from
that afforded by the combustion of hydrogen; a circumstance owing
to the presence of particles of carbon in the carburet, which being
intensely ignited, are highly luminous.
It is no less strange than true, that bicarburetted hydrogen, the
substance which we so largely consume to illuminate our towns, is ether
when united to water in one proportion, and spirit when combined with
it in another; a fluid which constitutes the strength of all wines,
beer, and fermented liquors.