OCR Text |
Show COMMON OAK, This valuable tree is well known to bea native of Britain, whereit has in some instances acquired an extraordinary magnie tude: its wood is justly preferred for ship-building. Oak saw-dust is the principal indigenous vegetable used in dyeing fustian. All the varieties of drabs, and different shades of brown, are made with oak saw-dust, variously managed and compounded. Oak applesare likewise used in dyeing as a substitute for galls, An infusion of the }b with a small quantity of copperas, is used by the common people to dye woollen of a purplish blue, which is sufficiently durable. But the chief use of the bark of this treeis for the process of tanning. Before we detail the process, it may be proper to observe, that raw hides and skins being composedof minute fibres intersecting eaclt other in every direction, the general operation of tanning consists chiefly in expanding the pores, and dissolving asort of greasy substance contained in them ; and then, by means of the astringency and gummyresinous properties of oak bark, to filland reunite them, so as to give firmness and durability to the whole texture. But this theory has been controverted by some chemists, who suppase that the animal jelly contained in the skin is not dissolved, but unites during the process with the astringent principle of the bark, and forms a combination inso- COMMON OAK. QUERCUS ROBUR. Class XXX. Moneecia. Order VI. Polyandria. Essent, Gen. Cuan. Male flewer—Calyx five-cleft: Corolla nes ae mina ten; Female flower—Calyz monophyllous, entire, rough: Corolla none: Siyles two orfive: Seed one, ovate. . r 7roundish: ish: JNut ob: Lobes Leaves oblong5)smooth, sinuate Spec. Caar. i we fons. lon a DESCRIPTION. rT 7 z ‘ nnct not T nis tree is the king of the forest, and has a most noble ape af pearance. ry 2 . Jeeply ‘The leaves have a peculiar shape, being aeep?) and forined into bh Theflowers are inconspi A . Sel cut, ’ «adam sheaves he footsté votstalks. standing upon short : 28 afterwards b co but the fruit : e first conspicnous, being fixed in a cup, and probably was the } nourishment of man, luble in water. The process of tanning varies considerably, not only in dif. ferent countries, but even in different parts of the same country. ‘he following is the method most approved and practised in London andits vic uty, where the best leatheris generally allowed to be manufactured. The leather tanned in Eng ind consists chieflyJ of three sorts 2 known by the name of Guéés or backs, hides, and skins. Butts are generally made from the stoutest and heaviest ox hides, and are anaged as follows: After the horns ‘are taken off, the hides are laid smooth in heaps for one or two days in the summer, and five or six in the winter: they are then hung on poles in a close roomcalled a smoke-house, in which is kept ‘smouldering fire of wet tan; this occasions a small degree of Putrefaction, by which means the hair is easily got off, by spread- |