WAX

WAX

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the wax to fmall pieces like bran. The wholeof the wax is then melted in a clean copper withboiling water, and {trained by a prefs throughcloth bags, to free it from every impurity. Itis then call into cakes, in which form it is re-ceived by the wax-refiners.

The wax of thefe cakes, which is the ordi-nary bees wax of the {hops, is a pale yellow fub-ftance, of an agreeable honey-like fmell, foft,and fomewhat unctuous to the touch, but with-out {ticking to the fingers, in winter becomingconfiderably hard and tough, and melting atabout 142°.

This yellow colour and the fmell of wax areentirely taken away by expofing it, when dividedinto thin lamina;, to the united aft ion of thelight and air, and by this means it becomesperfectly white, fcentlefs, fomewhat harder andlefs greafy to the touch, and in this ftate it isemployed for candles and many other purpofes.The procefs of bleaching wax is the following : aThe yellow wax is firft broken into fmall piecesand melted in a copper cauldron along with avery little water, juft fufficient to prevent thewax from burning, for it is of importance toufc no more heat than is neceffary. The plugof the copper is then drawn, and the melted waxand water fall together into a vefiel below,where it is covered with a thick cloth to keepin the heat for fome time, that the water andimpurities may fettle. The clear melted waxis then fuffered to flow into a veflel with thebottom full of fmall holes about the fixe of agrain of wheat, whence it falls in fmall ft reamsupon a cylinder kept conftantly revolving overWater in which it partly dips, by which the waxis immediately cooled, and at the fame timedrawn out into thin fhreds or ribbands. Thefe{hreds are then fpread upon cloths ftretched onlarge frames, which are fupported a foot or twofrom the ground, and after expofure to the funand air for feveral days, with frequent turning,their yellow colour nearly difappears. Thehalf-bleached wax is then heaped up in a folidmafs, and allowed to remain for a •month or fixweeks, after which, to give it compleat white-nefs, it is re-melted, and ribbanded, and bleachedas before, till it is entirely void of colour andfmell. Some manufacturers add in the re-melt-ing either alum or cream of tartar, or fometimesmilk, all of which are fuppofed to increale thewhitenefs and folidity of the wax.

Inftead of i'preading the ribbands of wax oncloths, fome employ a broad courfe of brickslaid evenly, which are frequently watered to• Encycl. Arts ct Met . > Bollock in Phil

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prevent the wax from melting by the heat ofthe fun abforbed by the bricks.

Wax is frequently adulterated by tallow, fuet,or animal fat of fome kind or other. This givesthe mixture a greater fufibility, fo that whenribbanded and expofed to a hot fun it is ex-tremely apt to cake. It alfo takes away from itthe femi-tranfparency, which is a diftinguiftiingproperty of pure bleached wax; for though finetallow is full as white as wax, it is always adead opake white. The adulteration may alfobe deteCted by boiling alcohol, which diflolve*wax but not tallow.

Bleached wax burns with a very pure whitelight, and gives no offenfive fmell, and verylittle fmoke compared with tallow. Being lefsfufible than tallow it requires a fmaller wick.Bleached wax melts at about 15 or 7 0 higherthan the unbleached. Its fpecific gravity is lefsthan that of water, being about .9 b.

Alcohol has no fenfibie aCtion cm wax whencold, but on boiling this fluid, it diffolves ratherlefs than of its weight of wax, the greaterpart of which feparates when cold in the form ofwhite bulky flocculi, and what little remains infolution is entirely precipitated by water. bSulphuric ether diffolves wax when a littleheated, and much move copioufly than alcoholdoes, but the greater part is alfo feparated bycooling and the remainder by water.

When wax is boiled in cauftic potafti, thefluid becomes turbid, but after a time moft ofdie wax rifes to the furface, and in a flocculentform. The clear alkaline liquor then holds infolution a portion of the wax, which may befeparated by an acid, and the part that remainson the furface is fo far fiiponified as to have loftits inflammability, and to be as foluble in purewater as white foap is, and again prccipitable byacids nearly in its original form, with its inflam-mability reftored. Pure ammonia adds nearlyas the fixed alkalies, but the refulting fapona-ceous feum is lefs foluble in water.

If wax is diftilied with a heat greater thanthat of boiling water it is deco npofed. c Afmall quantity of water firft rites-, which i, fol-lowed by a very penetrating volatile acid (pro-bably a modification of the acetous) accom-panied with a little very fluid and odoriferousoil. As the diftillation advances- the acid be-comes ftronger, and the oik much more copiousand thicker, till-at laft its confiftence is fuch asto become folid in the receiver, when it is calledButter of If 'ax. When tile heat is raifed to lowrednefs, and every thing volatile has come over,. Juura. Vol. iv. p, 184-, • Maccpur’s Difi,