1382. To make an Illuminated or Phosphoric Bottle, which will preserve its Light for several months.—By putting a piece of phosphorus, the size of a pea, into a phial, and adding boiling oil until the bottle is a third full, a luminous bottle is formed; for, on taking out the cork, to admit atmospheric air, the empty space in the phial will become luminous.
Whenever the stopper is taken out in the night, sufficient light will be evolved to show the hour upon a watch; and if care be taken to keep it, in general, well closed, it will preserve its illuminative power for several months.
1383. To Marble Books or Paper.—Marbling of books or paper is performed thus:—Dissolve four ounces of gum arabic in two quarts of fair water; then provide several colors mixed with water in pots or shells, and with pencils peculiar to each color; sprinkle them by way of intermixture upon the gum-water, which must be put into a trough, or some broad vessel; then, with a stick, curl them, or draw them out in streaks to as much variety as may be done. Having done this, hold your book, or books, close together, and only dip the edges in, on the top of the water and colors, very lightly; which done, take them off, and the plain impression of the colors in mixture will be upon the leaves; doing as well the ends as the front of the book in like manner, and afterwards glazing the colors.
1384. To Write Secretly on a Pocket Handkerchief.—Dissolve alum in pure water, and write upon a fine white handkerchief, which, when dry, will not be seen at all; but when you would have the letters visible, dip the handkerchief in pure water, and it will be of a wet appearance all over, except where it was written on with the alum water.
You may also write with alum water upon writing paper, which will not be visible till dipped in water.