eet oil upon the surface, and put
it to stand where it can get cold, and where no one will touch it. When
cold, put in a stick, and the fluid, previously clear, will at once
become opaque, and begin to crystallize, until at length there is a
solid crystalline mass.

ICE ON FIRE.

Make a hole in a block of ice with a hot poker. Pour out the water, and
fill up the cavity with camphorated spirits of wine. Then ignite the
spirit with a match, and the lump of ice will seem to be in flames.

EXPERIMENTS REQUIRING CHEMICAL SOLUTIONS.

To prepare these solutions, purchase of a druggist a small quantity of
the solid crystals of the substance needed for the experiment you wish
to try. Dissolve the crystals in clear pure water, and keep the solution
in a little bottle, labeled with the name. It is seldom that the
solutions need be strong. When the crystal is a colored one, enough
should be used to give the water a light tint, blue, yellow, or what it
may be. None of these solutions will do any harm to the hands, unless
there is a cut or a wound of any kind upon the skin. It is well also,
not to let a drop of any of them fall upon the clothes, or upon
furniture, for some of them will stain. And none of them should ever be
tasted, or touched by the lips or tongue, many of them being acrid and
even poisonous.

With the acids still greater care is needed, the stronger acids being
corrosive and poisonous. The greater portion of these substances must
likewise not be smelled, as the fumes or vapors would affect the
nostrils painfully.

For the proper performance of these experiments with solutions,
etc.,--at all events for the neatest and most elegant performance of
them,--there should be obtained from the chemist's shop about a dozen
test-tubes. These are little glass vessels, manufactured on purpose, and
very cheap. Do not take glasses that may afterward be used for drinking
or household purposes. Be careful to have every one of your experiment
glasses perfectly clean.

_To produce a Beautiful Violet-Purple Color._

Take a nearly colorless solution of any salt of copper. The sulphate
is the cheapest and handiest. Fill the test-tube or other
experimenting-glass about two-thirds full. Then drop in, slowly, a
little liquid ammonia. It will cause a beautiful blue to appear, and
presently a most lovely violet-purple, which, by stirring with a glass
rod, extends all through the fluid.

If now you drop into this a very littl