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the different {hops, often have fcarcely anyother refemblance than in colour. The beft fortof dragon’s blood is found in irregular roundifhpieces about the fize of a walnut, often wrap-ped in palm leaves, and of a deep uniform dullred colour, without fmell or talle. Whenbroken, its texture appears homogeneous, butevidently cellular. If a little of it is rubbedmuch in a mortar the colour brightens, andfomewhat approaches that of vermiliion.

Pure dragon’s blood is entirely infoluble inwater, but totally foluble in alcohol, forming atimflure of a fine blood-red colour. It burnswith a bright flame, and readily confumes'leaving only a fmall portion of a white afh.When charred by fulphuric acid, ioo grs. leave48 grs. of coal.

Dragon’s blood is foluble in the effential oils,and alfo in the fixed, giving them a fine redcolour. This refin is largely ufed in Varnijhing,(which lee) in lacquering, and painting, wherea full bodied deep red is wanted.

10. Gum Elemi. This refin comes overfrom South America in femi-pellucid yellowifhmaffes generally wrapped up in leaves, andvifibly contaminated with bits of twigs andbark, friable in the fingers, foftening by heat,of a fragrant fmell and bitterilh talle, Thetree that yields it is fuppofed to be the AmyrisElemifera.

Water diffolves only about T V of this refin,and the remainder is loluble in alcohol.

11. Gum Hedera is a refin which exfudes inhot countries from the llalks and leaves of theivy, (Hedera Helix .)

It appears in hard compact maffes, reddifhbrown externally, internally of a bright yellow,nearly opake, brittle, and with a gloffy vitreousfradture. The fmell is agreeable when rubbed,the talle flightly allringent. It is not entirelyfoluble either in water or alcohol, fo that inftridlnefs it ought hardly to be called a truerefin. It is little known, and has not beencarefully examined.

12. Labdanum or Ladanum. This refin ex-fudes fpontaneoufly from the leaves and branchesof a fragrant fhrub (Cijlus Creticus ) which growsabundantly in the dry mountainous regions ofthe Ifle of Candia, Syria , and other parts ofthe Levant . Ladanum is a black, hard, heavy,refinous mafs, rough externally, and in frag-ments, and its frafture fliews diilindt fparklingparticles. When chewed it gives a gritty feelto the mouth, and a bitterilh tafle, but doesnot dilblve. The fmell is fragrant. Whendigefted with water it imparts its grateful fmell,

but does not fenfibly diffolve therein. Bydiltillation it gives a fragrant effential oil, and atallelefs brittle refin remains. Alcohol diffolvesall the refin, and always Ihews in the undifl'olvedrefidue a confiderable quantity of fand andother impurities.

13. Majlich. This very valuable refin isprocured from the Pijlacia Lentifcus , a treethat grows to ten or twelve feet high, and iscultivated in many parts of the Levant , par-ticularly in the ifland of Chio.

The bell maftich is in the form of fmallroundilh tears, hard and brittle, of a faintyellow colour, nearly tranfparent, with a lightbut pleafant fmell, and little or no talle.When chewed it foftens in the mouth, andexcites a confiderable flow of faliva. It isnearly infoluble in water, but gives it a pleafantflavour when boiled with it. Alcohol and theeffential oils diflolve maftich entirely, forminga clear light-yellow tenacious folution, whicheither alone or with other refins is much em-ployed in varnilhing and other arts. Whencharred by fulphuric acid, 100 grains afford 66of charcoal.

14. Sandarac. This refin exfudes from thebark of feveral kinds of Juniper, and concretesin nearly pellucid yellowilh tears of a pleafantfmell, and fcarcely any tafle. It is compleatlyfoluble in alcohol, and in oils fixed or effential,and is much ufed in varnilhing.

15. Tacamahacca. This refin is obtained

from the Fagara oEhmdra, a tree found in manyparts of South America . There are two fortsof this refin; the beft is collefted in gourdIhells, and is undtuous and foft, of a greenilhyellow colour, a delightful fmell approachingto that of lavender, and a bitterilh aromatictalle. It is feldom ufed. *

16. Slyrax, or Storax, is a very fragrant refinprocured from the Styrax offiinalis, a middlingfized tree, a native of Alia. There are two fortsof this refin; the Styrax calamita, compofed ofreddilh brown maffes of a waxy confiitence, andfree from vifible impurities. The other, whichis by much the ccmmoneft fort, is fo largelyadulterated with faw-duft, that it looks ratherlike a mafs of faw-duft fomewhat agglutinatedby means of a foft clammy refin. Commonllyrax infufed in water gives it a golden colour,a fragrant fmell, and a flight balfamic talle.Diftillation with water Hill further impregnatesthis liquid with the fame qualities of fmell andtalle, and contains benzoic acid, which may beextracted in the way mentioned under thisarticle. When llyrax is diftilled per Je it yields