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lion of proper glutinous matters, the varnish is spread upon thepiece with a brush or pencil. The first coat being dry, the pieceis again and again washed over with the varnish till the colour ap-pears sufficiently deep. What is called gilt leather, and manypicture-frames, have no other than this counterfeit gilding. Forplain frames, thick tin-foil may be used instead of silver. Thetin-leaf, fixed on the piece with glue, is to be burnished, then po-lished with emery and a fine linen-cloth, and afterwards with puttyapplied in the same manner: being then lacquered over with var-nish five or six times, it looks very nearly like burnished gold.The same varnish, made with a less proportion of the colouringmaterials, is applied also on works of brass. A varnish of the con-sistence of thin turpentine is obtained for aerostatic machines, bythe digestion of one part of elastic gum, or caoutchouc, cut intosmall pieces, in thirty-two parts of rectified oil of turpentine. Pre-viously to its being used, however, it must be passed through alinen-cloth, in order that the undissoived parts may be left behind.Oil-Furnishes. Gum-copal and amber are the substances princi-pally employed in oil-varnishes; as they possess solidity and tran-sparency. The copal is used for varnishing light, the amber fordark colours. It is best to dissolve them before mixing them withthe oil. They should be melted in a pot on the fire ; and are in aproper state for receiving the oil when they give no resistance tothe iron-spatula, and when they run off from it drop by drop.When the oil is well mixed with the copal or amber, take it offthe fire; and when it is pretty cool, pour in a greater quantity ofthe essence of turpentine than the oil that was used. After thevarnish is made, it should be passed through a linen-cloth. Oil-varnishes become thick by keeping; but when they are to beused, it is only necessary to pour in a little essence of turpentine,and to put them for a iittle on the fire. The followiug are themost useful oil-varnishes. While Copal-Famishes. On sixteenounces of melted copal pour four, six, or eight, ounces of linseed-oil, boiled, and quite free from grease. When they are well mix-ed, take them off the fire, and when pretty cool, pour in sixteenounces of the essence of Venice turpentine. Amber-varnish ismade in the same way. For Couches and Iron-Work. This var-nish is composed of two ounces of bitumen of Palestine, twoounces of resin, with amber, melted separately, and afterwardsmixed ; six ounces of oil is then added, and afterwards the turpen-tine, as directed above. Golden-coloured varnish may he made• also by substituting linseed-oil for alcohol. Essential Oil -Far-7iishes. They are for pictures. They are usually made of gum-mastich and turpentine dissolved together in some essential oil,and are applied cold to tin: picture. Famish for Glass. Pul-verise a quantity of gum-adragant, and let it dissolve for twenty-four hours in the white of eggs well beat up ; then rub it gentlyon the glass with a brush. Varnishes before they are used shouldbe carefully kept from dust. When used, they should be liftedlightly with a brush, and spread upon a ground altogether freefrom dirt and moisture. The substance, after being varnished,should he exposed to the heat of the sun, or placed in a warmroom covered with a glass-case. Oil-varnishes require more heatthan alcohol-varnishes. The varnish should he put oti veryquickly, making great strokes with the pencil or brush, taking careluat these strokes never cross one another; it should he spreadequally, and never thicker than a leaf of paper; a second coatshould" not he put on till the first is quite dry. if the varnish,after being put on, becomes dull and uneven, it must be taken offentirely, and new varnish put on. To recover colours or varnish,and to take off the dirt and filth which may adhere to them, a leyis used made of potass, and the ashes of lees of wine. Take forty-eight ounces of potass, and sixteen of the above-mentioned ashes,and put them into six quarts of water, and the ley is made: insteadof the ashes an equal quantity of potass would probably do as well.To clean dirty colours, dilute some of this ley with four times itsquantity of water, and rub the picture with it; then wash it withriver-water; and when dry, give it a coat or two of varnish. Inorder to take off a varnish, wash it with the above-mentioned leythen with water, and then lift it off the substance on which it waswith any iron-instrument. The Chinese varnish is not a composi-tion, but a resin which exudes from a tree called in China tsi-ebu, “ varnish-tree.” This tree grows in several provinces of thesouthern parts of China . They do not procure varnish from thetsi-chu until.its trunk is nearly five inches in diameter, which size

I it seldom attains to before seven or eight years. This liquor distilsonly in the night-time, and during the summer-season. To causethe gum to How, they make several rows of incisions found thetrunk, the number of which is proportioned to the vigour of thetree. They are made towards evening, and next morning theycollect the varnish which has fallen into the shells; the followingevening they are again inserted, and this operation is continueduntil the end of the summer. A thousand trees yield almost inone night twenty pounds of varnish. While the varnish distils, itexhales a malignant vapour, the bad effects of which can only heprevented by preservatives and great precaution.

Varnish, among medallists, signifies the colours antique medalshave acquired in the earth.

VARN 1SH, in pottery, signifies a sort of shining coat, where-with potter’s ware, delft-ware, china-ware, &c. are covered, whichgives them a smoothness and lustre. Melted lead is generallyused for the first, and smalt for the second. See Glazing.

VARRO, Marcus Terentius, a Roman writer , was bornB. C. 118. He served under Pompey against the pirates, andobtained a naval crown. He wrote a treatise on the Latin lan-guage, and another De Re Ilustica, which are extant, with somefragments of Menippean satires. They were printed at Venice1474, fol. and Rome 1537, 8vo. He died B. C. 29.

VARRONIA, in botany, a genus of plants in the class pentan-dria, and order monogynia; natural order, Asperifolix. Corollafive-cleft; drupe with a four-celled nut. There are nine spe-cies.

VAS, [Lat.] a vessel either for mechanical, chemical, culinary,or any other uses. In anatomy, all the parts which convey a fluidare called vessels, as the veins, arteries, and lymphatics.

VASA CONCORDIiE, among hydraulic authors, are twovessels so constructed as that one of them, though full of wine,will not run a drop, unless the other, being full of water do runalso.

VASE , a term frequently used for ancient vessels dug fromunder ground, or otherwise found, and preserved in the cabinetsof the curious. In architecture, the appellation vase is also givento those ornaments placed on cornichcs, focldcs, or pedestals, re-presenting the vessels of the ancients particularly those used in sa-crifice, as incense-pots, flower-pots, &c.

VASSAL , in our ancient customs, signified a tenant or feuda-tory person, who vowed fidelity and homage to a lord, on ac-count of some land, &c. held of him in fee; also a slave orservant, and especially a domestic of a prince. See FeodalSystem.

VATERIA, in botany, a genus of the polyandria monogyniaclass and order. Calyx live-clelt; corolla five-petaled; capsulethrce-valved, one-celled, three-seeded. There is only one spe-cies, viz. V. Indica.

VATICA, in botany, a genus of the dodecandria monogyniaclass and order. Calyx five-cleft; petals five; anthers fifteen,sessile, four-celled. There is hut one species, viz. V. Cbinensis,a very rare plant, and as yet scarcely known.

VATICAN , a magnificent palace of the pope, in Rome, whichconsists of several thousand rooms: but the parts of it most ad-mired are the grand staircase, the pope’s apartment, and especiallythe library, which is one of the richest in the world, both m print-ed hooks and manuscripts.

VAUBAN, Sebastian le Prrstrf, lord of, a celebrated en-gineer. He displayed his knowledge of fortification in the courseof many sieges, and his services were rewarded with the first mili-tary honours. He was made governor of Lisle in 1668, commis-sary general of the fortifications of France in 1678, governor of themaritime pails of Flanders in 1689, and marshal of France in 1703.He died in 1707. lie wrote, I. The French Engineer, 8vo. 2. ATreatise on the Attack and Defence of Places, 8vo. 3. Essayson Fortification , 12mo. 4. Political Testament of M. Vauban.

VAUDOIS, VALDENSICS, or WALDKNSES, in eccle-siastical history, a name given to a sect of reformers. Theyformed religious assemblies, first in France , and afterwards inLombardy , from whence they propagated their sect throughout theother provinces of Europe with incredible rapidity, and with suchinvincible fortitude, that the most cruel inventions of mercilesspersecution could not damp their zeal, nor entirely ruin theircause. They did not attempt to introduce new doctrines into the

church.