[Footnote 6:  See Chapter XI.]

What is Copperas?

A kind of vitriol.  Copperas is the name given to green vitriol, which is a preparation from iron.  The blue vitriol is a sulphate of copper, and the white vitriol a sulphate of zinc.

For what is Vitriol used?

In the making of glass, to color it; in many arts and manufactures; and in medicine.

What are Galls?

Excrescences formed on a kind of oak tree in certain warm climates; perforations are made by an insect into the bark of the tree, whence issues a liquid which hardens by exposure.  They are used in dyeing, making ink, and other compositions.  There are two sorts of oak galls in our shops, brought from the Levant, and the southern parts of Europe.

What does the word Levant signify?

A country to the eastward.  It is applied to the countries of Turkey, Greece, Asia Minor, Syria, Egypt, &c., which are washed by the eastern part of the Mediterranean.

Is the Ink used in Printing the same as writing Ink?

No; it is more of the nature of paint, being thicker and more glutinous:  it chiefly consists of a mixture of oil and lamp-black, or some other ingredient, according to the color required; and is remarkable for the ease with which it adheres to paper that is moistened.

     Glutinous, gummy, resembling glue.

What is Indian, or Chinese Ink?

An admirable composition, not liquid like our ink, but solid, and made into cakes somewhat like the mineral colors we use in painting.  It is made into all sorts of figures, usually long, and about an inch thick; sometimes gilt with the figures of birds, flowers, &c.  To use this ink, it must be rubbed with water, on stone or earthenware, till it produces a beautiful, liquid, shining black.  It is used in drawing, &c., and is brought from China.  It is composed of lamp-black and size, or animal glue, or gum, to which perfumes and other substances are sometimes added.

CHAPTER X.

ASBESTUS, SALT, COAL, IRON, COPPER, BRASS, ZINC, AND LAPIS CALAMINARIS.

What is the name of the remarkable stone of which a cloth has been made, that resists the action of fire?

The Asbestus, a mineral substance of a whitish or silver color.  There are several species of this mineral, which are distinguished by different names, according to the appearance of each, as fibrous asbestus, hard asbestus, and woody asbestus; it is the fibrous sort which is most noted for its uses in the arts.  It is usually found inclosed within very hard stones; sometimes growing on their outside, and sometimes detached from them.

     Fibrous, full of fibres or threads.

What are its qualities?

It is insipid; will not dissolve in water; and exposed to the fire, it neither consumes nor calcines.  The industry of mankind has found a method of working upon this untoward mineral and employing it in making cloth and paper; the process is, however, difficult.