Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/629

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hard in, by the rotation of the Wooden ball. Thus you have a TcJ} finished, which, together with its earthen pot, mull be fet in a dry warm place.

To make the TeJU in the other manner, or by means of an iron ring, let a ring of that metal be filled with allies mixed with brickduil, and moiftened as before-mentioned, in fuch manner that they may rife confiderably above the ring ; then prefs them ftrongly either with your hands, or with an in- dented peirle, and afterwards, with gentle blows of a ram- mer, piefs the aihes from the circumference toward the cen- ter, in a fpiral line, and that in fuch manner, that, after hav- ing been fufHcientlv preffed, they may be a fmall matter higher than the brink of the ring. If there are now any vacancies in the mafs, empty the ring, and fill it again with more alhes j for if you mould attempt to fill up thefe by adding, were it but ever fo little afhes, the fecond, or additional quantities, will never cohere fo firmly with the firft, but that they may probably feparate in the operation.

This done, turn the ring upfide down, and on the other fide,' or bottom, take out the afhes to the quantity of one third part of the depth of the ring, and again fill the vacuity with the fame allies, in fuch a manner that there may remain no fenfi- ble cavity.

JVhen the mafs is thus prepared, cut out a cavity in the larger furfacc of the ring, with a bowed iron, as in the former me- thod.

The Germans have, befide thefe, another kind of Teflsi wiiich they call treibfebtrbm. Thefe are a fort of veffels which refill the uioft violent fire, and are fo extremely com- pact, that they foinetimes will retain not only melted metals, but even the glafs of lead itfelf.

The figure and fize of thefe veffels may be the fame with that of the coppel, but they are ufually made larger; and the great difference of thefe Tefts from coppels, and from the or- dinary Ttfis, which are indeed only a kind of large and coarfe coppels, is, that the matter of thefe is more compact and co- herent.

The matter for the making thefe Tefts is thus prepared : Take of the pureft and fineft clay a fufficient quantity, make it into balls, and dry them either in the air, or in the fire ; when dried, beat them to powder in a mortar, and pour on the powder a great quantity of warm water : Let this mixture reft a while, and when the clay has fubfided, pour off the water which fwims at top ; and let this waflling be fo often repeated, that all the moll minute lumps of the clay be broken, and whatever fait it contains perfeflly wafhed out : Then add to this fine clay, of the purefl fand, of powder of calcined flints, ground, and well waihed, of faulty, but clean Heffian cruci- bles, or of any incombuftible flones ground very fine, fuch a quantity as will render the mafs thick, and hardly adhering to the hands in kneading it, or pliant when rolled into a thin la- mina.

This is the matter for making this fort of lifts ; but before any quantity of the veffels be made of this earth, it will be prudent firft to finifli a fingle one, and try it, by putting on it a quantity of glafs of lead, and expofing it for an hour or more to the flrongefl fire ; by this trial you will be certain whether or not the mafs is capable of making veffels that will refill both the fire and the glafs of lead ; and by no other means but this trial is it poilible to determine the due proportion of the mixture of the ingredients for this ufe, on account of the va- riety of the clays. Nature in fome places affords a clay fo well tempered, that it is extremely proper for the making of Tejh without any preparation, or without the admixture of any other matter. Sometimes this only requires a fimple warning, but commonly it is neceflary to make it into balls, and pow- der and wafh them as before directed.

On the trial of a Teji made of this, or the former mixed clay, if it runs into glafs, you mufl add to it of the powder of Hone's, efpecially fuch as bell refill the fire. Great care is to be taken not to add too much powdered chalk to thefe compofitions, ftnee if the matter is tempered with that alone, the Tejls will indeed rend the fire very well, but being, too porous, they will yield a paffage to litharge, which will foften them to fuch a degree, that they will either fall afunder of themfelves, or be totally crufhed when taken hold of with the tongs. Thefe veffels are to be made in the following manner : Rub over the fides and bottom of a fmall mortar, and alfo its peflle, with oil, or with the fat of bacon ; fill it two thirds full of prepared clay, then make a flight impreflion with your fingers in the middle of the clay ; then place the bottom of the peflle there, and force it down with blows of a hammer, the ftronger the better. When thus properly hollowed, take it out of the mortar, and pare its edges, and dry it as the cop- pels are dried, in the air, in a dry warm place. Cramer's Art of Aff. p. 60, 62.

lefts, thus prepared, may be ufed as foon as dry, unlefs for falls, or litharge ; but thefe bodies, when melted in veffels not firft baked or hardened in the fire, always make their way thro' them. Test Liquor, a term ufed by our dealers in brandies, ISc. for a liquor which they ufe as the Tift of brandy, effr. to prove whether they be genuine, or mixed with home fpirit, Suppl. Vol. II.

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The people who ufe this, place great confici^nc:- m ic, bui it is really a very vague and uncertain thing. They pretend; that this liquor will mew by the colour which it makes, on being poured into brandy, whether it be genuine and unadul- terated ; or if not, in what proportion the adulterating ipirit is mixed with it.

The whole fa£t is this : If a little common green or white vi- triol bediflblved in fome fair water, it makes. a T.eji liquor ; a few drops of which being let fall into a glafs of old French brandy^ will turn the whole to a purple, or fine violet- colour ; and by the ftrength or palenefs of this colour, the dealers judge the brandy to be genuine or mixed, in different proportions, with home (pints.

Old French brandy, having long lain in the cafk, takes a di- lute tincture of the wood of the cafk,that is, of oak 3 and this being of the fame nature with a folutkm or tincture of galls, naturally turns bluifli or blackifh with vitriol. A new diftilled brandy, tho' wholly foreign, would not give this Teft ; and a common malt fpirit, with oak chips infufed in it, will turn as dark as the fineft. brandy^ While our difliliers indeed had no- thing in ufe for the colouring their fpirits but burnt fugar, it was poffible to make fome guefs at an adulteration with them, becaufe the brandy, in this cafe, would not become blackifh in proportion to its former colour, the fugar-colour not turning to ink with the vitriol like the other : But our diffillers have of late found a way of ufing an extract of oak for the colouring of their fpirits, and, fince that, this Tejt- liquor is of very little ufe, our common fpirits, of any kind, turning as deep with it as the foreign brandies. The very belt way of making this Teft-liqmr, is with a cal- cined vitriol of iron, diflbived in a dilute or aqueous mineral acid. The liquor, when well made in this manner, is of a fine yellow colour, and will give, for a time, the fineft blue to any fpirituous tin&urc of oak.

The Englifh were, at one time, very fond of high- coloured brandies, and it was then that the ufe of this Tejl-Uqzicr was moffc efteemed ; afterwards we, as well as other nations, finding that this colour was only owing to the cafk, began to diflikc it, and to favour the pale brandies: At length we fell into the ufe of fuch as were wholly limpid and colourlefs, arid the re-diifillingof all the old brandies people were poffefTed of took place ; on this, the Teji-l'tquor was found to be of no ufe at all, and accordingly rejected j but as we are of late again come into the efteem of coloured brandies, and that with great juftice, as the colour, when genuine, is a certain mark of the age of the liquor, this Teji-liquor is again got into more credit than it deferves.

The famous Helvetian ftyptic depended wholly on this acci- dent for its colour ; and it was no fmall mortification to our chemiffs, when, fome years ago, it was introduced into ufe among us, that they could not make it with our own fpirits, but mufl be at the expence of true French brandy for it ; our own fpirits, though equally coloured, would never make that violet tincture, becaufe their colour was owing to burnt fu- gar, not a tincture of oak. At length this myfterv was ex- plained, and a little fcrapings of galls made all thole quantities of this ftyptic, which had been fet by as good for nothing, perfectly fine and well coloured. Shaw's Eflay on DifHUery. TESTA, in antiquity, the fame with ojlracm. See the article

OsTRACON.

TESTES {Cycl.) Thefe are wanting in mnft of the fifh kind. The fpinofe fifhes in general have neither Tefies nor paraltatse ; but all the cetaceous fifhes have them, and not a few of the cartilaginous kinds. Thofe fifh that have them, have always two, as in land animals ; but they differ much in figure and fituation in the feveral kinds, particularly in the whale and flat fifh. Artedi Ichthyol.

TESTICLE (Cycl.) humours In the Testicles. Tumours and inflammations of one or both the TejUdes are not un- frequently the confequence of falls, blows, and contufions s and very often are alfo brought on by venereal diforders. The beft external applications to difperfe thefe are vinegar of litharge, lime-water, fpirit of wine camphorated, and eerufs, tutty, or lapis calaminaris mixed in it. But in the night-time, when the applications of fomentations are not fo convenient, a platter of the mercurial kind, doubly fated with mercury, or, in flight cafes, one of fimple diachylon, may very properly be kept on. Internal medicines, fuch as nitre, and the thin de- coctions of difcutlent remedies^ are to be ufed; and, ifocca- fion call for it, bleeding in the arm is very proper. This may be the method with tumours of thefe parts, from, external injuries ; but when they are from venereal caufes, it is always neceflary to give brifk purges, with the addition of a proper dofe of calomel to each, and warm and weak drinks fhould be taken frequently, and by this means thefe tumours are often difperfed. But if either remedies are applied too late, or the inflammation is very violent, the tumour generally ends either in a fuppuratlon or gangrene. In this cafe the matu- rating remedies are to be applied, fuch as warm cataplafms, and the like j and if the tumour does not break of itfelf at a proper time, from the applicationof thefe, it muft be carefully opened with the knife, and the matter being difcharged, the wound is to be clsanfed by injecting vulserary deco&lons with K h h h a