TEREBINTHIXA VULGARIS. 605 



different species have arisen the diverse methods of obtaining the 

 terebinthinous resins. 



Thus in the wood of the Silver Fir (Pinups Picea L.) resin-duets are 

 altogether wanting; — and led by experience, the Alpine peasant collects 

 the turpentine of this tree by simply puncturing the little cavities which 

 form under its bark. In the Scotch Pine (P. silvestris L.), they are more 

 abundant in the wood than in the bark, a fact which might be anticipated 

 by observing how rarely this tree exudes resin spontaneously. 



Oil of turpentine, like volatile oils in general, undergoes on expo.sure 

 to the air certain alterations giving rise to what is called resinijiccition. 

 The formic acid which is produced in small quantity during this change 

 characterizes it as one of oxidation; the chief products however are not 

 exactly known, and not one of them has been proved identical with any 

 natural resin. The common assumption that resins are produced from 

 volatile oils by simple oxidation, is consequently not yet entirely 

 justified. 



Extraction — In the United States ^ turpentine is obtained to the 

 largest extent from Pinus aiiMralis, of which tree there are vast forests, 

 the piny woods or pine-barrens, extending from Virginia to the Mexican 

 Gulf, especially through North and South Carolina, Georgia and Ala- 

 bama. But it is in North Carolina that the extraction of turpentine is 

 principally carried on. 



In the winter, i.e. from November to March, the negroes in a 

 Turpentine Orchard, as the district of forest to be worked is called, are 

 occupied in making in the trunks of the trees, cavities which are 

 technically known as boxes. For this purpose a long narrow axe is 

 used, and some skill is required to wield it properly. The boxes are 

 made from 6 to 12 inches above the ground, and are shaped like a dis- 

 tended waistcoat-pocket, the bottom being about 4 inches below the 

 lower lip, and 8 or 10 below the upper. On a tree of medium size, a 

 box should be made to hold a quart. The less the axe approaches the 

 centre of the tree the better, as vitality is the less endangered. An ex- 

 pert workman will make a box in less than 10 minutes. From one to 

 four boxes are made in each tree, a few inches of bark being left between 

 them. The greater number of trees from which tuipentine is now 

 obtained, are from 12 to 18 inches in diameter, and have three boxes 

 each. 



The boxes having been made, the bark and a little of the wood 

 immediately beneath it, which are above the box, are hacked ; and from 

 this excoriation, the sap begins to flow about the middle of March, 

 gradually filling the box. Each tree requires to be freshly hacked every 

 8 or 10 days, a very slight wound above the last being all that is needed. 

 The hacking is carried on year aft^r year, until it reaches 12 to 15 feet 

 or more, ladders being used. The turpentine, which is called cU}), is 

 removed from the boxes by a spoon or ladle of peculiar form, and 

 collected into barrels, which are made on the spot and are of very rude 

 construction. The first year's flow of a new tree, having but a small 

 surface to traverse before it reaches the box, is of special goodness and 

 is termed Virgin dip. 



^ The account here given is taken from Slave States, New York, 1856, p. 338, eto. 

 F. L. Olmsted's Journey in the Seaboard 



