Shenandoah, Iowa.
Please describe the process of making sandpaper.
H. S. Galt.
Answer.—Common window glass—that having a green tint is best—is powdered and sifted through sieves of varying fineness, for coarse and fine sandpaper. Then any coarse paper is covered with thin glue and the powdered glass is sifted upon it. After standing a day or two, the refuse sand is shaken off, and the paper is ready for use.
ALABASTER.
Clinton, Ill.
Where is alabaster quarried and manufactured?
Old Pilgrim.
Answer.—Alabaster, or plaster of paris, is made in large quantities at Grand Rapids, Mich., where there are extensive beds of gypsum, the stone from which it is produced. Vases and other ornamental articles can be cut from the finest quality of this stone; but generally such articles are produced in Europe, where labor is cheaper and the class of workmen accustomed to this branch of art is numerous. The chief supply of European gypsum for fine arts is obtained at Sienna and other places in Tuscany, and manufactured at Florence, Milan, Leghorn, and Volterra.