The apparently empty or upper part of vessels in which wine or beer
is working, is filled with this deleterious gas; for its great
weight prevents its ascent from the fermenting liquid. A variety
of striking but simple experiments may be made with the gas in
this condition. Lighted paper, or a candle dipped into it, will be
immediately extinguished; and the smoke remaining in the carbonic acid
gas will render its surface visible, which may be thrown into waves
by agitation, like water. In consequence of the great weight of the
carbonic acid gas, it may be taken from a vat of fermenting liquor, in
a jug or bottle, and in the latter, if well corked, it may be conveyed
to great distances; or the gas may be drawn out of a vessel by a cock,
like a liquid.