Dissolved in water, it forms a beautiful and useful color for the painter.  It is also used in medicine.  Gamboge is soluble in either water or spirits of wine.  Mixed with a blue color, it forms green, in various shades according to the different proportions of the ingredients.

What is Logwood?

The wood of a tree which grows in parts of America and the West Indies.  It is imported in great quantities, and employed in dyeing purple and the finest blacks.

What is Tar?

A coarse, resinous liquor issuing from the wood and bark of pine or fir-trees; it is in fact the oily juices of the sap thickened and colored by the heat of the sun or by age; it is extracted for use by burning the wood of the trees under a heavy covering of turf or earth; the tar exudes during the slow combustion, and is collected into a cavity dug in the ground for the purpose.  Tar is exported in great quantities from Norway, Sweden, and our Southern States.

What are its uses?

It is applied to the sides of ships and boats and their rigging, to preserve them from the effects of the weather; it is used instead of paint for palings, &c.; and sometimes also in medicine.  A kind, called mineral tar, is also drawn from coal by the process of distillation.  Mineral tar is also found native in some parts of the earth.

What is Pitch?

A kind of juice or gum, likewise drawn from unctuous woods, chiefly those of the pine and fir; it is used for nearly the same purposes as tar in shipping, medicine, and various other arts.  Pitch is properly a juice of the wild pine, or pitch tree; it is of a glossy black color, dry brittle, and less bitter and pungent than the liquid tar.

What is Camphor?

A vegetable substance, chiefly procured from a kind of laurel, (Laurus Camphora,) growing in Borneo, Japan, and many East Indian islands; it is also produced from other plants and shrubs, though in very small quantities.

How, and from what part of the tree is it taken?

All parts of the tree are impregnated with camphor; but it is principally extracted from the roots and trunk, by distillation; it is white, and of a crystal form:  its odor is extremely fragrant.  In this state it is called rough camphor, and is thus exported.  The Greeks and Romans do not appear to have been acquainted with this valuable drug; and we are indebted to the Arabians for a knowledge of it.

What are the properties and uses of Camphor?

It is a firm, dry, crystal matter, with a hot, sharp, aromatic taste.  It is highly odorous, and so inflammable as to burn and preserve its flame in water; it totally vanishes or evaporates in the open air, and in Spirits of Wine it entirely dissolves.  Camphor has various uses—­as in fire-works, &c.; it is an excellent preservative of animal and vegetable bodies, as it resists worms and other insects.  In the courts of Eastern princes it is burnt at night with wax.  Its principal use with us is in medicine.