THE TECHNOLOGIST. [March 1, 1865. 



374 THE SUPPLY OF 



is called u Raze." After exhausting the tree for turpentine, the trunk 

 and root are distilled for tar, &c. 



Turpentine is abundant in all the parts of the Weymouth pine 

 (Pinus Strolus), but containing very little resin ; it volatilises rapidly, 

 and yields little at each extraction. 



The extraction of resin from the pine trees in the extensive forest of 

 Lairvaux (Morbihan) is about to be carried on on a large scale. For 

 that purpose several cargoes of earthenware cups have been imported at 

 Vannes. These are extremely simple, each cup resembling a small 

 flower-pot, with the difference that one of the sides is concave, so that 

 it can be fixed against the tree to be tapped, so as to facilitate the flow 

 of the sap when the tree is pierced. The wood of the pine which has 

 been tapped or resinated is considered in the Landes as far superior in 

 resistance and durability to that which has not been tapped, and with 

 good reasons. If the tapping exhausts the trees and reduces their 

 dimensions, it produces, on the other hand, wood of feebler growth, 

 and more charged with autumnal shoots ; it causes, besides, an active 

 flow of turpentine from the interior to the surface, of which the most 

 liquid effuses, losing in the woody tissues which it traverses a consi- 

 derable portion of resin. Therefore, the proportion of the resin the 

 trees contain determines their weight, solidity, durability, and inflam- 

 mability. 



The wood is not always the principal product of the pignadas, or 

 pine forests, for very often the timber is sacrificed for the turpentine. 

 It is principally in the Landes that the tapping is carried on on a large 

 scale ; it is generally performed in the following manner : — A tree is 

 ready for tapping as soon as it measures about four feet in circum- 

 ference at the base. The tapper, to prepare it for his work, thins with 

 his hatchet the bark where he intends to pierce it, and smooths it ; 

 then, with a special instrument, he makes a rectangular incision or 

 channel called " quarre," which lays the sap open ; it is generally a foot 

 long by one inch wide. At the lower part of the " quarre " he digs 

 a little trough in some protruding part of the stem to receive the 

 produce. 



If that is not possible he attaches a portable trough. Every week 

 the incision is renewed by cutting off a thin slice from the upper part, 

 so that it always increases in height, preserving the same width, or, 

 better still, decreasing in width, and in five years probably reaches a 

 height of about ten feet. Then it is abandoned, and a second one 

 commenced, conducted like the first, from which it is separated by a 

 belt of bark of two inches at most, and which is called " Ourle " or 

 " Bourrelet." This is done all round the tree, taking care to put each 

 " quarre" a little higher than the preceding one; then the belts 

 ("ourles") are attacked, which, in the meantime, have spread and 

 covered, more or less, the old wounds, and they are incised in the same 

 way. 



