AMALGAMS.

WHEN mercury is alloyed with any metal the compound is called an amalgam of that metal; as, for example, an amalgam of tin, bismuth, &c.

Amalgam for Electrical Machines.

1. Fuse 1 oz. of zinc with oz. of tin, at as low a temperature as possible; then add 1 oz. of quicksilver, previously made hot; mix, pour out, and when cold reduce it to powder, and triturate it with sufficient quicksilver to bring it to a proper consistence. 2. Zinc 1 part; tin 1; quicksilver 2. Melt together. 3. Zinc 2 parts; tin 1; mercury 5.

4. La Beaume's. Pour into a chalked wooden box 6 oz. of quicksilver; put into an iron ladle oz. of beeswax, with 2 oz. of purified zinc, and 1 oz. of grain tin; set it over a brisk fire, and when the metals are melted pour them into the box, avoiding the dross. When cold reduce it to powder, and mix it with lard. Keep it in a box covered with tallow, and spread it on leather for use.

Liquid Amalgam for Silvering Globes, &c.

Pure lead 1 oz ; grain tin 1 oz.; melt in a clean ladle, and immediately add 1 oz. of bismuth. Skim off the dross, remove the ladle from the fire, and before the metal sets add 10 oz. of quicksilver. Stir together, avoiding the fumes.

Amalgam for Varnishing Plastic Figures.

Melt 2 oz. of tin with oz. of bismuth, and add 1⁄2 oz. of quicksilver. When cold grind it with white of egg, and apply to the figure.

VARNISHES.
Preparations of Lac.

Stick-lac consists of twigs of several kinds of trees encrusted with a resinous matter, produced by the puncture of an insect called the cocus lacca. This, triturated with water, and dried, forms seedlac. The seed-lac, when heated and pressed in cotton bags, forms shell-lac. Lac dye is the coloring matter extracted from stick-lac by water, and evaporated to dryness, with the addition of earthy matters, and formed into square cakes. Seed-lac and shell-lac are chiefly used in varnishes, dissolved in rectified spirits, or rectified wood naphtha. The alcoholic solution is rendered paler, so that it may be used for polishing light colored woods, by digesting it in the sun, or near a fire, for two or three weeks, with good animal charcoal, and then filtering it through paper in a funnel heated with hot water. Shell-lac may be bleached by dissolving it in a solution of potash, or soda, and passing chlorine into the solution.

4.

The precipitated lac is collected, and well washed. Kastner directs 3 parts of carbonate of potash to be dissolved in 24 of water, and 3 of lime added, and the whole digested in a close vessel for twenty-four hours. The clear liquor is poured off, and boiled with 4 parts of shell-lac. When cold, dilute with 4 times its bulk of water, and filter; then add chloride of lime, and afterwards diluted muriatic acid. With these preliminary remarks we come now to the lacquers, or varnishes.

The Famous Brilliant French Varnish for Boots and Shoes. Take of a pint of spirits of wine; 5 pints white wine; pound of powdered gum senegal; 6 oz. loaf sugar; 2 oz. powdered galls; 4 oz. green copperas. Dissolve the sugar and gum in the wine. When dissolved, strain; then put it on a slow fire, being careful not to let it boil. In this state put in the galls, copperas, and the alcohol, stirring it well for five minutes. Then set off, and when nearly cool strain through flannel, and bottle for use. It is applied with a pencil brush. If not sufficiently black a little sulphate of iron, and half a pint of a strong decoction of logwood, may be added, with oz. pearlash.

16

Black Varnish,

Take any varnish, of the class you wish, 16 parts; lampblack 2 parts. Grind the black in a small quantity of the varnish, then mix it with the remainder.

Cabinet-makers' Varnish.

Pale shell-lac 700 parts; mastic 65 parts; strongest alcohol 1000 parts. Dissolve. Dilute with alcohol.

Callott's Soft Etching Varnish.

Linseed oil 8 parts; benzoin 1 part; white wax 1 part. Melt and keep it heated until reduced to two thirds.

Pale Carriage Varnish.

Copal 32 parts; pale oil 80 parts. Fuse and boil until stringy; then add dried white copperas 1 part; litharge 1 part. Boil again, then cool a little, and mix in spirits of turpentine 150 parts. Strain. While making the foregoing, take of gum animé 32 parts; pale oil 80 parts; dried sugar of lead 1 part; litharge 1 part; spirits of turpentine 170 parts. Pursue the same treatment as before, and mix the two compositions while hot.

Second Quality of Carriage Varnish.

Take of gum animé 32 parts; oil 100 parts; spirits of turpentine 150 parts; litharge 1 part; dried sugar of lead 1 part; dried copperas 1 part. Proceed as above.

Copal Varnish.

Copal 30 parts; drying oil 25 parts; spirits of turpentine 50 parts. Put the copal into a vessel capable of holding 200 parts,

and fuse it as quickly as possible, then add the oil, previously heated to nearly the boiling point. Mix well, then cool a little, and add the spirit of turpentine; again mix well, and cover up until the temperature has fallen to 140° Fah.; then strain.

To Dissolve Copal in Spirit.

Take the copal and expose it in a vessel formed like a colander to the front of a fire, and receive the drops of melted gum in a basin of cold water; then well dry them, in a temperature of about 95° Fah. By treating copal in this way it acquires the property of dissolving in alcohol.

Black Copal Varnish.

Take lamp-black, or ivory-black, in fine powder, and mix it with the varnish.

Blue Copal Varnish.

Indigo, Prussian blue, blue verditer, or ultra-marine. These substances must be powdered fine. Proceed as before.

Fine Pale Copal Varnish.

Pale African copal 1 part. Fuse, then add hot pale oil 2 parts. Boil until the mixture is stringy, then cool a little, and add 3 parts of pale spirits of turpentine. Mix well.

Flaxen Grey Copal Varnish.

Ceruse, which forms the ground of the paste, mixed with a small quantity of Cologne earth, as much English red, or carminated lake, and a particle of Prussian blue, and color the varnish therewith.

Green Copal Varnish.

Verdigris, crystallized verdigris, compound green (a mixture of yellow and blue). The first two require a mixture of white in proper proportions, from a fourth to two-thirds, according to the tint intended to be given. The white used for this purpose is ceruse, or the white oxide of lead, or Spanish white. Proceed as before.

Improved Copal Varnish.

Caoutchoucine (white and scentless), strong alcohol, equal parts; copal in the proportion of two pounds to a gallon. Digest in a close vessel, without heat, for one week.

Pearl Grey Copal Varnish.

White and black; white and blue; for example, ceruse and lamp-black; ceruse and indigo. Mix them with the varnish, according to the tint required.

Purple Copal Varnish.

Prussian blue and vermilion, or any other blue and red; then proceed as before.

Red Copal Varnish.

1. Vermilion, red oxide of lead (minium), red ochre, or Prussian red, &c., and proceed as before.

2. Dragon's blood, brick red, or Venetian red, &c., and proceed as before.

Violet Copal Varnish.

Vermilion, blue, white, in proportions required to color the varnish.

White Copal Varnish.

Copal 16 parts; melt, and add hot linseed oil 8 parts; spirits of turpentine 15 parts; finest white lead to color.

Yellow Copal Varnish.

Yellow oxide of lead, or Naples and Montpelier, both reduced to impalpable powder. These yellows are hurt by contact with iron or steel. In mixing them, therefore, a horn spatula, with a glass mortar and pestle, must be employed. Or gum gutta, yellow ochre, or Dutch pink, according to the nature and tone of the color to be imitated, and proceed as before.

Mastic Varnish.

Gum mastic 5 pounds; spirits of turpentine 2 gallons. Mix with a moderate heat (carefully applied), in a close vessel, then add pale turpentine varnish 3 pints. Mix well.

Another.

Mastic 1 pound; white wax 1 ounce; oil of turpentine 1 gallon. Reduce the wax and mastic small, then digest in a close vessel, with heat, until dissolved.

Common Oil Varnish.

Resin 4 pounds; genuine beeswax 1⁄2 pound; boiled oil 1 gallon. Mix with heat, then add spirits of turpentine 2 quarts.

Turpentine Varnish.

Resin 1 part; boiled oil 1 part. Melt, then add turpentine 2 parts. Mix well.

White Hard Spirit Varnish.

Gum sandarach 2 pounds; alcohol (65 op.) 1 gallon. Place them in a strong, well closed vessel, and apply the heat of warm water, with occasional agitation, until dissolved; then add pale turpentine varnish 1 pint. Mix well, and let the whole rest for twenty-four hours, when it will be ready for use.

White Spirit Varnish.

Strongest alcohol 100 parts; sandarach 25 parts; parts; elemi 3 parts; Venice turpentine 3 parts. closely corked vessel.

tears mastic 6 Dissolve in a

·Varnish for Toys.

Copal 7 parts; mastic 1 part; Venice turpentine & part; strongest alcohol 11 parts. Dissolve the copal first, with the aid of a little camphor, then add the mastic, &c., and thin with alcohol, as required.

To Clean Varnish.

Use a ley of potash, or soda, mixed with a little powdered chalk. Do not make the liquor too strong of the alkali.

To Polish Varnish.

Take 2 oz. powdered tripoli, put it in an earthen pot, with water to cover it; then take a piece of white flannel, lay it over a piece of cork or rubber, and proceed to polish the varnish, always wetting it with the tripoli and water. It will be known when the

process is finished by wiping a part of the work with a sponge, and observing whether there is a fair even gloss. When this is the case, take a bit of mutton suet and fine flour, and clean the work.

Varnish for Harness.

Take pound of India-rubber; one gallon of spirit of turpentine; dissolve enough to make it into a jelly; then take equal quantities of good hot linseed oil, and the above mixture. porate them well on a slow fire, and it is fit for use.

Incor

A Varnish for Fastening the Leather on Top Rollers in Factories. Dissolve 24 oz. of gum arabic in water; and a like amount of isinglass dissolved in brandy, and it is fit for use.

A Varnish to Preserve Glass from the Rays of the Sun. Reduce a quantity of gum tragacanth to fine powder, and let it dissolve for twenty-four hours in white of eggs well beat up; then rub it gently on the glass with a brush.

A fine Black Varnish for Coaches and Iron Work.

Bitumen of Palestine 2 oz.; resin 2 oz.; umber 12 oz. Melt them separately, and then mix together over a moderate fire. Then pour upon them, while on the fire, 6 oz. clear boiled linseed oil, stirring the whole from time to time. Take it off the fire, and when moderately cool pour in 12 oz. of essence of turpentine.

Varnish for Clock Faces.

Spirits of wine 1 pint; divide it into four parts; mix one part with an oz. of gum mastic in a bottle by itself; one part of spirit and oz. gum sandarach in another bottle; and one part spirit and oz. whitest part of gum benzoin. Mix and temper them to suit; if too thick add spirit; if too thin a little mastic; if too soft some sandarach or benzoin. When about to use it warm the silvered plate before the fire, and with a flat camel-hair pencil stroke it over till no white streaks appear; this will preserve it for many: years.