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Show 794 SCOTCH FIR. SCOTCH FIR. of London and Edinburgh direct it to be made into an ointment (unguentum picis); the former, by means of the admixture of an equal portion of mutton suet, and the latter, of two-fifths of yel- low wax. This ointment has been employed for thecure of cu. taneous affections, particularly those of domestic animals. Some practitioners have applied a plaster of tar for the cureof ~ nate cases of tinea capitis, and not without success; but it isa very painful, and almost a cruel remedy, forit eae be taken off without dragging out of the skin adheringtoit the roots of the hair, in the eradication of which, in fact, consists the only use of the plaster. Pircu. The usual mode of making pitcl 1 consists in melting coarse hard resin (or Jrai-sec, as it is called in France) with an equal i of tar, iin n large large copper copper vessels similar toto those those usedfor quantity vessels similar proj ili juice tar be the proportionof be too thin, the the tar Iff the the raw juice. boiling thick, a third be it if hand, other the on and increased; is resin part of tar is sufficient. Should the process of inspissation be ec to iits utmost mos limit,; the pitch becomes quite hard and carried Enea, and wicca atte (thea ticoa rt pi. arida dry, andis i called iin the shopss piw ‘ . ; which i less a 68 and a pungent less is which writers), Greek marwaoow of the externa ae some 80 in only7 in’ use is used and ar,, and a the commontar th bitter sitter than ‘ } Ate el ae ont applications, as an adhesive substance agreeing in its medicin virtues with the commondigestives. and nts i ae i ointme and fats, fats, into ins, and resins, oi oils, ith When melted with plasters, pitch is said to be very apt to separate andprecipitate. Hr shining, 0 odorous being shining, i as being i the Ibest pitch Dioscorides describes alities wer i qua hich the were which i : and of a reddish black colour, 8rummy, aa 1 Calabrian pitch. It was prescribed byhim, a pitch. of the Lycian and Calabrian for maturing g mé in plasters for ingredient in andalso by Celsus, as a proper ingredient vendita abscesses and healing wounds. ed by e by the arantients for ggiving Hav th employed was3 much i Pitch and fragrance to their wines, which werealso supposed v2 La fromit useful medicinal properties, as we have before ane i when speaking of the properties of terebiuthinate fag ner general. Their mode of pitching casks and other Te ih dctibed by Columella. We are told by Pliny of a biaeieni' tar with vinegar, called Zrutia, which was employed a i - purposes; and this author says that it was usual to a first ferment of new wine, or mustum, with power ie ” In boiling down tar to dryness without addition, there come 795 over an acid liquor in considerable quantity, and also an ethereal oil, which seems to differ from theoil of turpentine onlyin being impregnated with an empyreumatic quality ; it was called bythe ancients oleum picinum. ‘The medicinal properties of this oil are similar to those of tar. The extensive use of pitch and tar in ship building is too well knownto require particular mention. A mixture of sitch and wax, by which crevices in vessels are rendered impermeab le to water, was called by the antients Zumiccn; and this substance, after it had been sometime steeped in the sea, was used medi. cinally as a resolvent. Blended with a certain quantity of oil and suet, pitch becomes an useful kers for vaxing their threads, and with whale fat it forms the grease with which wheels of carriages are smeared over. In several kinds of luting, also, this article possesses considerable utility, andis familiar to most mechanics and handicraftsmen, LAmp-Biack. Anyspecies of pine may be used for makir g lamp-black , but the general practice is to convert the impurities left in the pre. cipitation of tar and pitch tothis purpose. The mode followed in Germany is thus described by Axtius, who has been copied by Duhamel, and it is illustrated in the works of both these au. thors by engravings. A sort of box is made, nicely closed in every part, with the exception of some holes in the top, which are covered, however, with a sort of linen cone. Ata little distance from the box a furnace is constructed, with a very small mouth, and the inferior part communicating with the inside of the box by a horizontal chimney. Into this furnace are put the dregs and coarser parts left in the preparation oftar, and in Proportion to the consumption of these a supply is kept up, so as to furnish a constant draught of smoke to the box. The smoke goes chiefiy into the cone, whereit deposits its grosser parts in the form of soot, which, when beaten off from thelinen ysucks applied on the outside, is collected from the upper part of the box aud putintobarrels. Lamp-black is employed almost exclusively in printing and dyeing in the present d t it was formerly used as a substi« tute for the juligo thuris, which is mentioned by Dioscorides and Celsus as a resolvent and digestive, and formed an ingredi ent in some of their plasters. ‘The first of these authors describes a |