CRYSTALLIZATION OF METALS.
Some of the metals assume certain definite forms in returning from the fluid to the solid state. Bismuth shows this property more readily than most others.
EXPERIMENT.
Melt a pound or two of bismuth in an iron ladle over the fire; remove it as soon as the whole is fluid; and when the surface has become solid break a hole in it, and pour out the still fluid metal from the interior; what remains will exhibit beautifully formed crystals of a cubic shape.
Sulphur may be crystallized in the same manner, but its fumes when heated are so very unpleasant that few would wish to encounter them.
One of the most remarkable facts in chemistry, a science abounding in wonders, is the circumstance, that the mere contact of hydrogen, the lightest body known, with the metal platinum, the heaviest, when in a state of minute division, called spongy platinum, produces an intense heat, sufficient to inflame the hydrogen: of course this experiment must be made in the presence of atmospheric air or oxygen.
Time and space (or rather the want of them) compel us to conclude with a few experiments of a miscellaneous character.
TO FORM A SOLID FROM TWO LIQUIDS.[7]
Prepare separately, saturated solutions of sulphate of magnesia (Epsom salts) and carbonate of potash. On mixing them the result will be nearly solid.
[7] Saturated solutions are made by adding the salt to boiling water until it will take up no more, letting it stand till cold and then pouring off the liquid.