1377. To cut Glass.—Take a red-hot shank of a tobacco-pipe, lay it on the edge of your glass, which will then begin to crack; then draw the shank end a little gently before, and it will follow any way you draw your hand.
1378. Mrs. Hooker's Method of preparing and applying a Composition for Painting in Imitation of the Ancient Grecian Manner.—Put into a glazed earthen vessel four ounces and a half of gum arabic, and eight ounces, or half a pint (wine measure) of cold spring water; when the gum is dissolved, stir in seven ounces of gum-mastic, which has been washed, dried, picked, and beaten fine. Set the earthen vessel containing the gum-water and gum-mastic over a slow fire, continually stirring and beating them hard with a spoon, in order to dissolve the gum-mastic; when sufficiently boiled, it will no longer appear transparent, but will become opaque and stiff, like a paste. As soon as this is the case, and the gum-water and mastic are quite boiling, without taking them off the fire, add five ounces of white wax, broken into small pieces, stirring and heating the different ingredients together, till the wax is perfectly melted, and has boiled. Then take the composition off the fire, as boiling it longer than necessary would only harden the wax, and prevent its mixing so well afterwards with water. When the composition is taken off the fire, and in the glazed earthen vessel, it should be beaten hard, and whilst hot (but not boiling) mix with it, by degrees, a pint (wine measure) or sixteen ounces more of cold spring water; then strain the composition, as some dirt will boil out of the gum-mastic, and put it into bottles. The composition, if properly made, should be like a cream, and the colors when mixed with it as smooth as with oil. The method of using it, is to mix with the composition, upon an earthen pallet, such colors in powder, as are used in painting with oil, and such a quantity of the composition to be mixed with the colors as to render them of the usual consistency of oil colors; then paint with fair water. The colors, when mixed with the composition, may be laid on either thick or thin, as may best suit your subject; on which account, this composition is very advantageous, where any particular transparency of coloring is required; but in most cases it answers best if the colors be laid on thick, and they require the same use of the brush as if painting with body colors, and the same brushes as used in oil painting. The colors, if ground dry, when mixed with the composition, may be used by putting a little fair water over them; but it is less trouble to put some water when the colors are observed to be growing dry. In painting with this composition, the colors blend without difficulty when wet, and even when dry the tints may easily be united by means of a brush and a very small quantity of fair water. When the painting is finished, put some white wax into a glazed earthen vessel over a slow fire, and when melted, but not boiling, with a hard brush cover the painting with the wax, and when cold take a moderately hot iron, such as is used for ironing linen, and so cold as not to hiss, if touched with anything wet, and draw it lightly over the wax. The painting will appear as if under a cloud till the wax is perfectly cold, as also whatever the picture is painted upon is quite cold; but if, when so, the painting should not appear sufficiently clear, it may be held before the fire, so far from it as to melt the wax but slowly; or the wax may be melted by holding a hot poker at such a distance as to melt it gently, especially such parts of the picture as should not appear sufficiently transparent or brilliant; for the oftener heat is applied to the picture, the greater will be the transparency and brilliancy of coloring; but the contrary effect would be produced if too sudden or too great a degree of heat was applied, or for too long a time, as it would draw the wax too much to the surface, and might likewise crack the paint. Should the coat of wax put over the painting, when finished, appear in any part uneven, it may be remedied by drawing a moderately hot iron over it again, as before-mentioned, or even by scraping the wax with a knife; and should the wax, by too great or too long application of heat, form into bubbles at particular places, by applying a poker heated, or even a tobacco-pipe made hot, the bubbles would subside; or such defects may be removed by drawing anything hard over the wax, which would close any small cavities.
When the picture is cold, rub it with a fine linen cloth. Paintings may be executed in this manner upon wood (having first pieces of wood let in behind, across the grain of the wood, to prevent its warping), canvas, card, or plaster of Paris. The plaster of Paris would require no other preparation than mixing some fine plaster of Paris, in powder, with cold water, the thickness of a cream; then put it on a looking-glass, having first made a frame of bees'-wax on the looking-glass, the form and thickness you would wish the plaster of Paris to be of, and when dry take it off, and there will be a very smooth surface to paint upon. Wood and canvas are best covered with some gray tint, mixed with the same composition of gum-arabic, gum mastic, and wax, and of the same sort of colors as before-mentioned, before the design is begun, in order to cover the grain of the wood or the threads of the canvas. Paintings may also be done in the same manner, with only gum-water and gum-mastic, prepared the same way as the mastic and wax; but instead of putting seven ounces of mastic, and, when boiling, adding five ounces of wax, mix twelve ounces of gum-mastic with the gum-water, prepared as mentioned in the first part of this receipt; before it is put on the fire, and when sufficiently boiled and beaten, and is a little cold, stir in, by degrees, twelve ounces, or three-quarters of a pint (wine measure) of cold spring water, and afterwards strain it. It would be equally practicable painting with wax alone, dissolved in gum-water in the following manner: Take twelve ounces, or three-quarters of a pint (wine measure) of cold spring water, and four ounces and a half of gum-arabic, put them into a glazed earthen vessel, and when the gum is dissolved, add eight ounces of white wax. Put the earthen vessel, with the gum-water and wax, upon a slow fire, and stir them till the wax is dissolved, and has boiled a few minutes; then take them off the fire, and throw them into a basin, as by remaining in the hot earthen vessel the wax would become rather hard; beat the gum-water and wax till quite cold. As there is but a small proportion of water in comparison to the quantity of gum and wax, it would be necessary, in mixing this composition with the colors, to put also some fair water. Should the composition be so made as to occasion the ingredients to separate in the bottle, it will become equally serviceable, if shaken before used, to mix with the colors.
1379. The Best Season for Painting Houses.—The outside of buildings should be painted during autumn or winter. Hot weather injures the paint by drying in the oil too quickly; then the paint will easily rub off. But when the paint is laid on during cold weather, it hardens in drying, and is firmly set.
1380. A cheap and simple Process for Painting on Glass, sufficient for the purpose of making a Magic Lanthorn.—Take good clear resin, any quantity, melt it in an iron pot; when melted entirely, let it cool a little, and before it begins to harden, pour in oil of turpentine sufficient to keep it liquid when cold. In order to paint with it, let it be used with colors ground in oil, such as are commonly sold in color shops.
1381. To make Phosphorus.—Two-third parts of quick-lime (i.e. calcined oyster-shells), and one-third of flour of brimstone, put into a crucible for an hour, and exposed to the air for an hour, become phosphorus.