Provide a bottle of the gas chlorine, which may be purchased of
any operative chemist, and with it you may exhibit some brilliant
experiments.
For example, reduce a small piece of the metal antimony to a very fine
power in a mortar; place some of this on a bent card, then loosen the
stopper of the bottle of chlorine, and throw in the antimony, it will
take fire spontaneously, and burn with much splendour; thus exhibiting
a cold metal spontaneously bursting into flame.
If, however, a _lump_ of antimony be dropped into the chlorine, there
will be no spontaneous combustion, nor immediate change: but, in the
course of time, the antimony will become incrusted with a white
powder, and no chlorine will be found in the bottle.
Or, provide copper in fine leaves, known as “Dutch metal;” slightly
breathe on one end of a glass rod, about ten inches long, and cause
one or two leaves of the metal to adhere to the damp end; then open
a bottle of chlorine, quickly plunge in the leaves, when they will
instantly take fire, and burn with a fine red light, leaving in the
bottle a greenish-yellow solid substance.
A small _lump_ of copper, or “Dutch metal,” will not burn as above, but
will be slowly acted upon, like the antimony.
Immerse gold leaf in a jar of chlorine gas, and combustion with a
beautiful green flame will take place.