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may be dropped. When the quantityof alkali is very fmall, it requires a few minutesto produce the full change.

Tumeric is ufed largely in the Eaft as a con-diment to food, and in particular, it is the fub-ftance that gives the colour to curry.TURNSOLE. See Litmus.

TURPENTINE , and other ref nous productsof the Pine .

Under this head we {hall defcribe the me-thods of procuring and preparing a variety ofvery important articles 1 of commerce, iuch asturpentine, refill, pitch, tar, &c. which are em-ployed fo extenfively in (hip-building and rig-ging, in varnifhes, and many other purpofes ofinferior intered.

All thefe are the produdfs of one or otherfpecies of pine, and fometimes the fame fub-ftance is yielded by different fpecies, as all thevarieties of the native refin, or turpentine, havea very great refemblance in chemical properties.

There are three varieties of pine turpentine,commonly known under that name in Europe ;namely, id. the common turpentine , obtainedchiefly from the Pinus Sylvejlrts (Scotch Fir),■ad. the Strasburgh turpentine yielded by thePinus Picea (Sjlver Fir) and 3d. the Venice tur-pentine procured from the Pinus Larix (Larch ).To thefe may be added two liquid turpentines.4th. the Carpathian or Hungary Balfam, whichexfudes from the Pinus Gembra (Siberian StonePine). 5th. the Canada Balfam , the refinousjuice of the Pinus Balfamea (Balm of GileadFir ). The fine fragrant Chio turpentine is notprocured from a pine, but from a low fhrub(the Pfacia Lentifcits') which will be defcribedin the next article.

Of the three fird-mentioned turpentines, theVenice is the thinned and moft aromatjc, theStrafburg the next in thefe qualities, and theCommon is the firmed and coarfed. The twoformer are often adulterated by a mixture ofthe common turpentine and oil of turpentine,and it is to be obferved that the terms Veniceand Strafburg turpentine are not now appropri-ate, as they are procured from various coun-tries.

Common turpentine is obtained largely inthe pine foreds in the fouth of France , inSwitzerland , in the countries on the north ofthe Pyrenees, in Germany , and in many of thefoutliern dates of North America . The greaterpart of what is confumed in this country is im-ported from North America . The method of

obtaining it is by making a feries of incifion*through the bark of the tree, from which theturpentine exfudes, and falls down into holesor other receptacles at the foot. The procefsis defcribed very accurately by Duhamel andMoringlane as pra£fifed in the fouth of France .

The fir is generally allowed to remain un-touched till it is thirty or forty years old.When it is to be worked, which is early in thefpring, a fmall hole is fird made in the groundat the foot of the tree, the earth of which iswell rammed, and ferves as a receptacle for thejuice. The coarfe bark is then dripped offfrom the tree, a little above the hole down tothe fmooth inner bark, after which a portionof the inner bark together with a little of thewood is cut out with a very {harp tool, fo thatthere may be a wound in the tree about threeinches fquare, and an inch deep. Immediatelyafterwards the turpentine begins to exfude invery tranfparent drops, which efcape chieflyfrom the wood immediately under the innerbark. The hotter the weather is, the greateris the fupply of refin, and to facilitate the fup-ply the incifions are enlarged every three orfour days by cutting off thin dices, till at theend of the year it is about a foot and a halfwide and two or three inches deep. The wholetime during which the turpentine flow's is fromthe end of February to October. In the winterit entirely ceafes, but in the enfuing fpring afrelh incifion is begun a little above the former,and managed in the fame manner. This prac-tice is continued annually for about twelve orfifteen years in fome parts, and in others afhorter time, on the fame fide of the tree, tillthe later incifions are fo high as to be out ofreach without the aflidance of fteps; afterwhich the contrary fide of the tree is begunupon, and worked in a fimilar manner for asmany years, during which time the fird incifi-ons are growm up, and are fit to be cut afrefh.In this way, a healthy tree in a favourable foil,may be made to yield from fix to twelve ormore pounds of turpentine annually, fometimesfor a century, and even the timber is not fooninjured by this conftant drain.

The flow of turpentine difcontinues altoge-ther about October, and the liquid refin col-lected during the year from each tree, is puttogether for further purification. But a confi-derable quantity of the refin has concreted dur-ing that time around the incifion, particularlyas the heat declines; and in the winter when it

a Dr. Matons Supplement to Lambert on the Genus Pinus. Moringlane in the Journ. de Phyf. tom. 31.Murray’s Apparatus Medicam. Didt. d’Hift. Nat. Article Goudron, fcc. &c.