veffels, all the time,, remaining of a healthful green fuch are the alternus, orange-mint, &c. which, being ftrengthened by rich manure, or being inarched in healthful plants, throw off the diftemper. 3. In other plants, the difeafe is fo rooted and inveterate, that it is propagated with the feed: fuch are the archangel, water-betony, bank-crefs, borrage, ftriped cellary, and fycamore, the fides of which produce ftriped plants. VARIOLÆ, the SMALL-POX, in medicine. See the article Pox.

VARIORUM, or cum notis VARIORUM, in matters of literature, denotes an edition of a claffic author, with notes of divers authors thereupon thefe editions are generally most valued. VARIX, in medicine, the dilatation of a vein, arifing from the too great abundance or thickness of the blood; the cure of which is to be attempted by evacuations, as phlebotomy and cathartics; as alfo by external applications, as difcutient fomentations, cataplafms, embrocations, &c. or, where the cafe grows dangerous, by incifion.

VARNA, a town of Bulgaria, in european Turky, fituated on the western coaft of the Black-fea, an hundred and twenty miles north of Conftantinople. VARNISH, or VERNISH, a thick, vifcid, fhining liquor, ufed by painters, gilders, and various other artificers, to give a glofs and luftre to their works; as alfo to defend them from the weather, duit, &c. There are several kinds of varnishes in ufe; as the ficcative or drying varnish, made of oil of afpin, turpentine, and sandarach melted together. White varnish, called alfo venetian varnish, made of oil of turpentine, fine turpentine, and maftic. Sipirit of wine varnish, made of fandarach, white amber, gum elmi, and maftic; ferving to gild leather, picture-frames, &c. withal. Also the gilt-varnish, chinavarnish, common-varuifh, &c.

1. To make the white varnish take gum fandarach, of the cleareft and whitelt fort, eight ounces; gum maltic, of the cleareft fort, half an ounce; of farcocolla, the whiteft, three quarters of an ounce; venice turpentine, an ounce and a half; benzoin, the cleareft, one quarter of an ounce; white rofin, one quarter of an ounce; gum animæ, three quarters of an ounce: let all these be diffolved, and mixed in the manner following:

Put the farcocolla and rofin into a little more spirits than will cover them to disfolve; then add the benzoin, gum animæ, and venice-turpentine, into either a glass or glazed earthen veffel, and pour on as much fpirits as will cover them an inch; then put the gum-maftic into a glafs or glazed veffel, and pour strong fpirits upon it, covering it alfo about an inch thick, to diffolve it rightly; then put your gum elemi into a diftinct veffel as before, and cover it with fpirits to

diffolve.

For this purpose, you need only break the rofin a little, and powder the gum animæ, farcocolla, and benzoin.

Let all ftand three or four days to dif folve, shaking the glasses, &c. two or three times a day, and afterwards put them all together into a glazed vessel, ftirring them well, and strain the liquor and gums gently, beginning with the gums, through a linen-cloth.

Then put it into a bottle, and let it ftand a week before you use it, and pour off as much of the clear only, as you think fufficient for prefent use.

2. The white amber-varnish is thus made according to Mr. Boyle: take white rofin four drams, melt it over the fire in a clean glazed pipkin; then put into it two ounces of the whiteft amber you can get, finely powdered. This is to be put in by a little and a little, gradually, keeping it ftirring all the while with a fmall ftick, over a gentle fire, till it diffolves, pouring in now and then a little oil of turpentine, as you find it growing stiff; and continue fo to do till all your amber is melted.

But great care must be taken not to fet the house on fire, for the very vapours of the oil of turpentine will take fire by heat only; but if it should happen fo to do, immediately put a flat board or wet blanket over the fiery pot, and by keeping the air from it you will put it out, or fuffocate it.

Therefore it will be beft to melt the rolin, in a glass of a cylindric figure, in a bed of hot fand, after the glass has been well annealed, or warmed by degrees in the fand, under which you must keep a gentle fire.

When the varnish has been thus made, pour it into a coarfe linen-bag, and prefs it between two hot boards of oak or flat plates of iron; after which it may be fed with any colours in painting, and

allo

alfo for varnishing them over when painted.

But for covering gold, you must use the following varnish: mean time, it is to be obferved, that when you have varnished with white varnifli, you may put the things varnished into a declining oven, which will harden the varnish.

3. A hard varnish that will bear the muffle, may be thus made: take of colophony, an ounce; fet it over the fire in a well-glazed earthen veffel, till it is melted; then by little and little, ftrew in two ounces of powder of amber, keeping it firring all the while with a stick; and when you perceive it begin to harden or refift the ftick, then put in a little turpentine oil, which will thin and foften it immediately; then put in two ounces of gum copal, finely powdered, fprinkling it in as you did the amber, now and then pouring in a little oil of turpentine; and when it is done, ftrain it as before directed.

This is proper to varnish over gold; and the things done with it must be fet into a declining oven, three or four days fucceffively, and then it will refift even the fire itself.

4. To make a varnish for brafs, that will cause it to look like gold. Take two quarts of fpirit of wine, and put it into a retort-glass; then add to it an ounce of gamboge, two ounces of lacca, and two ounces of maftic; fet this in a fand-heat for fix days, or elfe near a fire, or you may put the body of the bolt-head frequently into warm water, and shake it two or three times a-day; then set it over a pan of warm faw-duft. But before this varnish is laid over the metal, let it be well cleaned.

This is a good varnish to mix with any colours that incline to red, and the amber-varnish for mixing with those that are pale.

5. To make a varnish for gold, or metals made in imitation of gold. Take colophony, and, having melted it, put in two ounces of amber finely powdered, and some spirit of turpentine, and, as the amber thickens, keep it well firring; then put in an ounce of gum elemi, well pulverized, and more (pirit of turpentine; conftantly ftirring the liquor till all is well mixed and incorporated: but take care, however, to ufe as little turpentine as you can, becaufe, the thicker the varnih is made, the harder it will be. Let VOL, IV,

this be done over a fand-heat, in an open glafs; then train it, as is directed for the preceding varnish. This varnish is to be used alone, firft warming the veffels made of paper- pafte; and lay it on with a painting-bruth before the fire, but not too near, left the fire raise it into blifters. After this has been done; harden it three feveral times in ovens ; first with a flack heat, the next with a warmer, and the third with a very hot one; and the veffels will look like polished gold.

And as for fuch veffels, &c. as fhall be made with faw-duft and gums, the var nish may be made of the fame ingredients as above-mentioned, except the gumelemi; and this will dry in the fun, or in a gentle warmth.

6. To make a varnish for any thing covered with leaf filver. First paint the thing over with fize, and ground chalk or whiting; let them ftand till they are thoroughly dry, and then do them over with very good gold-fize, of a bright colour (for there is much difference in the colour of it; fome being yellow, and others almoft white; the first is most proper for gold, and the laft for filver.) When this fize is fo dry as that it will just stick a little to the touch, lay on the leaf-filver, and close it well to the fize. 7. To make a varnish for filver. Melt, in a well glazed pipkin, fome fine turpentine, and put in three cunces of white amber, finely powdered (more or lefs, according to the quantity your work will require) put it in by little and little, keeping it continually stirring, adding by degrees fome fpirit of turpentine, till all the amber is diffolved; and then add to it an ounce of farcocolla well beaten, and an ounce of gum elemi well levigated, adding now and then a little fpirit of turpentine, till all is diffolved: do this over a gentle fire, and keep it conftantly stirring.

This varnish will be as white and flrong as the former; and is to be used warm, and hardened by degrees in an oven, as varnished gold, whereby it will look like polished filver.

Laying on of VARNISHES. 1. If you varnith wood, let your wood be very smooth, clofe-grained, free from grease, and rubbed with rufhes. 2. Lay on your colours as imooth as poffible; and, if the varnish has any blifters in it, take them off by a polish with xufhes. 3. 19 D

While

its rife from the whole external fide of the femur; and both together, with the cruralis and rectus, form a very robuft and ftrong tendon juft above the knee, to which the patella adheres behind, and which is inferted below the knee at a tubercle of the tibia. See MUSCLE. VAT, or FAT, a veffel for holding wine, ale, beer, cyder, &c, in the time of their preparation.

VATERIA, in botany, a genus of the polyandria-monogynia clafs of plants, the flower of which confifts of five oval and patent petals; and its fruit is a turbinated, coriaceous, and unilocular capfule, containing a single oval feed. VATICAN, a magnificent palace of the pope, in Rome, which is faid to confift of feveral thoufand rooms: but the parts of it most admired are the grand staircafe, the pope's apartment, and efpecially the library, which is one of the richest in the world, both in printed books and manufcripts.

VAUDEMONT, the capital of a county of the fame name in Lorrain, fifteen miles fouth-west of Nancy. VAUDOIS are certain valleys Gtuated north of the marquifate of Saluzzo, in Italy: the chief town is Lucerne. See the article LUCERNE.

VAUDREVANGE, a town of Lorrain, fituated on the river Sare, fifty miles north-east of Nancy.

VAUGE, high mountains of Alface in Germany, which separate it from Lorrain on the west.

VAULT, fornix, in architecture, an arched roof, fo contrived that the ftones which form it fuftain each other. See ARCH. Vaults are, on many occafions, to be preferred to foffits or flat ceilings, as they give a greater height and elevation, and are befides more firm and durable. See the article CEILING.

Salmafius obfever, that the antients had only three kinds of vaults. The first was the fornix, made cradle-wife; the fecond a teftudo, i, e, tortoile- wife, which the French call cul de four, or cven-wife; and the third concha, or trumpet-wife. But the moderns have fubdivided these three forts into many more, to which they have given different names, according to their figures and ufes; fome of them are circular, and others elliptical. Again, the fweeps of fome are larger, others lefs, portions of a sphere. All fuch as are above hemifpheres, are called high, or furmounted, vaults; and all 6

that are less than hemifpheres, are called low, or furbafed, vaults, or teftudines. In fome vaults the height is greater than the diameter; in others it is lefs: others, again, are quite flat, and only made with haunfes; others like ovens, or in the form of a cul de four, &c. and others growing wider as they lengthen, like a trumpet.

There are also gothic vaults, with ogives, &c. See the article OGIVE, &c.

Of vaults fome again are fingle, others double, crois, diagonal, horizontal, afcending, defcending, angular, oblique, pendent, &c.

Mafter VAULTS are thofe that cover the principal parts of buildings, in contradiftinction to the upper or fubordinate vaults, which only cover fome little part, as a paffage or gate, &c.

Double VAULT is one that is built over another, to make the outer decoration range with the inner; or, to make the beauty and decoration of the infide confiftent with that of the outlide, leav s a space between the concavity o The one and the convexity of the other. Instances of which we have in the dome of St. Peter's at Rome, St. Paul's at London, and in that of the invalids at Paris. VAULTS with compartments are fuch whose fweep, or inner face, is enriched with pannels of fculpture, feparated by platbands. Thefe compartments, which are of different figures, according to the vaults, and ufually gilt on a white ground, are made with tone or brickwalls, as in the church of St. Peter at Rome, or with plaister on timber-vaults. Theory of VAULTS. A femi-circular arch or vault, ftanding on two piedroits, or impofts, and all the flones that compofe them, being cut, and placed in fuch manner as that their joints or beds, being prolonged, do all meet in the center of the vault; it is evident that all the tones must be in the form of wedges; ie, mult be wider and bigger at top: by virtue of which they fuftain, each other, and mutually oppofe the effort of their weight, which determines them to fall.

The tone in the middle of the vaults, which stands perpendicular to the horizon, and is called the key of the vult, is fuftained on each fide by two contiguous ftones, just as by two inclined planes; and, confequently, the effort it makes to fall is nor equal to its weight.

But ftill that effort is the greater, as the inclined planes are lets inclined; fotha 19 D 2 if