CHAP. CXIII.

coni'fer;e. ^bif/tin*.

2125

Scotch pine: next to it is the larch, and after that the spruce fir. Whensome of the newly introduced American and Himalayan species are betterknown, perhaps they may rank as high as, or higher than, these European ones; but at present, with the exception of d'bies Douglash, which promises tobe a rapid-growing species, what they are likely ultimately to become inBritain must necessarily be only matter of conjecture.

Resinous substances have been extracted from the pine and fir tribe, sincethe days of Theophrastus , who has given (book ix. c. 10.) a very good ac-count of the process, which has been copied, with very little variation, by allauthors who have written on the subject, up to the time of Du Hamel ; andwhich, as Dr. Clarke observes, corresponds so well with the modern prac-tice in the north of Europe , that there is not the smallest difference betweena tar-work in the forests of Westro-Bothnia, and one in those of ancientGreece. Du Hamel ’s account forms the groundwork of an article on theresinous productions of the pine and fir tribe by Dr. Maton, published inLambert’s Genus Pinus, vol. ii.; but the most complete treatise on the sub-ject is in the Dictionnaire des Eaux et Forets, where the German practicesare given from Hartig and Burgsdorf; and those of France, Switzerland , andItaly , from modern authors of the respective countries. From these andother sources we shall here give what is general to all the .dbietinas; andunder the particular genera and species we shall insert the details for extract-ing and manufacturing the products peculiar to each. These products arevarious; but they may be all divided into two classes; viz. those obtained fromthe tree while it is in a living state, and those procured from the wood androots after the tree is cut down. The first kinds are extracted from the trunk ofthe tree by making incisions in the bark or wood, from which a resinous matterflows in greater or less quantity, according to the kind of tree; and from thisare procured, turpentine, liquid balsam, the common yellow and black rosins ofthe shops, oil and spirit of turpentine, and some minor articles. The otherkinds are procured from the trunk, branches, and roots, after the tree is cutdown, by the application of heat; and they include tar, pitch, lampblack, &c.The common turpentine is generally the produce of the pine; and the processfor obtaining and manufacturing it will be given under the head Binus. TheStrasburg and Venice turpentines are drawn from the silver fir and the larch(see -Picea and Barix); and the best yellow rosin is that of the spruce fir (seeA bies). The resinous matter drawn from the trunk of pine trees is put intobaskets, and placed over stone or earthenware jars. The fluid part, whichruns from it, is the common turpentine; and the solid part left in the basket,when purified by boiling, is the common yellow rosin. Oil, and rectifiedspirit of turpentine, are distilled from the raw turpentine, and the residuumlett after distillation is the black rosin, or colophony, used by players on(he violin for their bows. Tar is procured by cutting the wood and rootsinto small pieces, and burning, or rather charring them, in a close oven, orheap covered by turf, while a tube or trough is left near the bottom of theheap or oven, through which the tar runs, in the form of a thick black fluid,the Swedish tar is the most highly esteemed in commerce; and that ofArchangel ranks next to it. In the United States , Michaux informs 11 s, tar» generally made from dead wood collected in the forests, and on this account11 Is considered very inferior to the tar of Europe . The lampblack is the sootevolved during this process, and is collected from the upper part of the oven,or trom the turf which has covered the heap ; and pitch is merely tar boiled° dryness. The resinous matter of the spruce, like that of the pine, is col-whh * r0m “! c ' s * ons m ade in the bark; but it does not yield its turpentineoht • OU *', t ^ e heat and pressure. The resinous juice of the silver fir is

th t* 1 f co ^ ect * n g the natural exudations on the surface of i£k trunk; anda - °, ™e larch, from the interior of the trunk, by tapping it with an auger,to obtain the sap of the birch and the sugar maple,hav ^ ™ ein j ca l properties of the resinous juice of the pine and fir tribee been given at length by Dr. Maton, in Lambert’s Genus Pinus, from