exposed to a proper degree of heat. When the silver runs, it is taken from the fire and dipped into weak spirits of salts to clean it.

To Tin Copper and Brass.

Boil six pounds of cream of tartar, four gallons oí water, and eight pounds of grain tin or tin shavings. After the materials have boiled a sufficient time, the substance to be tinned is put therein, and the boiling continued, when the tin is precipitated in its metallic form.

To Tin Iron and Copper Vessels.

Iron which is to be tinned must be previously steeped in acid materials, such as sour whey, distiller's wash, &c.; then scoured and dipped in melted tin, having been first rubbed over with a solution of sal-ammoniac. The surface of the tin is prevented from calcining by covering it with a coat of fat. Copper vessels must be well cleansed; and then a sufficient quantity of tin with salammoniac is put therein, and brought into fusion, and the copper vessel moved about. A little resin is sometimes added. The sal-ammoniac prevents the copper from scaling, and causes the tin to be fixed wherever it touches. Lately, zinc has been proposed for lining ves sels instead of tin, to avoid the ill consequences which have beer unjustly apprehended.

To paint Sail-Cloth, so as to make it Pliant, Durable, and Water-proof.

Grind ninety-six pounds of English ochre with boiled oil, and add to it sixteen pounds of black paint. Dissolve a pound of yellow soap in one pail of water on the fire, and mix it while hot with the paint. Lay this composition, without wetting it, upon the canvas, as stiff as can conveniently be done with the brush, so as to ferm a smooth surface; the next day, or the day after, (if the latter, so much the better,) lay on a second coat of ochre and black, with a very little, if any, soap; allow this coat a day to dry, and then finish the canvas with black paint.

To make Oil-Cloth.

The manner of making oil-cloth, or, as the vulgar sometimes term it, oil-skin, was at one period a mystery. The process is now well understood, and is equally simple and useful.

Dissolve some good resin or gum-lac over the fire in drying linseed oil, till the resin is dissolved, and the oil brought to the thickness of a balsam. If this be spread upon canvas, or any other linen cloth, so as fully to drench and entirely to glaze it over, the cloth, if then suffered to dry thoroughly, will be quite impenetrable To wet of every description.*

* This preparation will likewise be found both useful and econo mical in securing timber from the effects of wet.

This varnish may either be worked by itself or with some colour added to it: as verdigris for a green; umber for a hair colour; white lead and lamp-black for a gray; indigo and white for a light blue, &c. To give the colour, you have only to grind it with the last coat of varnish you lay on. You must be as careful as possible to lay on the varnish equally in all parts.

A better method, however, of preparing oil-cloth is first to cover the cloth or canvas with a liquid paste, made with drying oil in the following manner: Take Spanish white or tobacco-pipe clay which has been completely cleaned by washing and sifting it from all impurities, and mix it up with boiled oil, to which a drying quality has been given by adding a dose of litharge one-fourth the weight of the oil. This mixture, being brought to the consistence of thin paste, is spread over the cloth or canvas by means of an iron spatula equal in length to the breadth of the cloth. When the first coating is dry, a second is applied. The unevennesses occasioned by the coarseness of the cloth or the unequal application of the paste are smoothed down with pumicestone reduced to powder, and rubbed over the cloth with a bit of soft serge or cork dipped in water. When the last coating is dry, the cloth must be well washed in water to clean it; and, after it is dried, a varnish com posed of gum-lac dissolved in linseed oil boiled with tur pentine is applied to it, and the process is complete The colour of the varnished cloth thus produced is yel low; but different tints can be given to it in the manner already pointed out.

An improved description of this article, intended for figured and printed varnished cloths, is obtained by using a finer paste, and cloth of a more delicate texture.

To prepare Varnished Silk.

Varnished silk, often employed for umbrellas, cover. ing to hats, &c., being impenetrable to wet, is prepared, and the operation performed, in the same manner as I have described in the second method of preparing oilcloth, but with a different kind of varnish or paste.

The paste used for silk is composed of linseed oil boiled with a fourth part of litharge; tobacco-pipe clay, dried and sifted, sixteen parts; litharge, ground on porphyry or very fine marble, and likewise dried and sifted, three parts; lamp-black one part. After the washing of the silk, fat copal varnish is applied instead of that used for oil-cloth.

To paint Cloth, Cambric, Sarcenet, &c., so as to render them Transparent.

Grind to a fine powder three pounds of clear white resin, and put it into two pounds of good nut oil, to which a strong drying quality has been given; set the mixture over a moderate fire, and keep stirring it till all the resin is dissolved; then put in two pounds of the best Venice turpentine, and keep stirring the whole well together; and, if the cloth or cambric be thoroughly varnished on both sides with this mixture, it will be quite transparent.

I should remark that in this operation, as well as in the preparation of oil-cloths and varnished silks, the surfaces upon which the varnish or paste is to be applied must be stretched tight, and made fast during the application.

This mode of rendering cloth, &c. transparent is excellently adapted for window-blinds. The varnish will likewise admit of any design in oil colours being executed upon it as a transparency.

To thicken Linen Cloths for Screens.

Grind whiting with flowers of zinc, and add a little honey to it; then take a soft brush, and lay it upon the cloth, repeating the operation two or three times, and giving it time to dry between the different coatings. For the last coat, smooth it over with linseed oil nearly boiling, and mixed with a small quantity of the litharge of gold-the better to enable the cloth to stand the weather.

Printers' Ink.

Printers' ink is a real black paint, composed of lampblack, and linseed oil which has undergone a degree of heat superior to that of any of the common drying oils.

The manner of preparing it is extremely simple. Boil linseed oil in a large iron pot for eight hours, adding to it bits of toasted bread, for the purpose of absorbing the water contained in the oil. Let it rest till the following morning, and then expose it to the same degree