42 THE PLANT WORLD. 



PLANT JUICES AND THEIR COMMERCIAL VALUES. 

 Bv Mi{s. Caroline A. Ckkkvky. 



[ ( 'onf'nnicd. I 



After the pine trees are exhausted by about ( 5 years of taj)pini2: for 

 turpentine, they are used for i)rocuriug tar. For this purpose the tree 

 is felle<l and cut into small lengths. A hole is dug in the ground, de- 

 pressed ill the centre, and clay bottom is laid. The trees, ])ranches 

 and all, are })laced in this hole around shavings and kindlings. After 

 lighting the shavings, the whole is covered with earth or turf. Hy 

 slow combustion, the tar is reduced to liquid. Hows into the basin-like 

 central depression, thence is drawn out in prepared channels and 

 loaded into barrels. About 100, (XMi l)arrels is the annual yield of 

 .Vmerican tar. 



Pitch is the solid residuum after (b'stillint; tar for tar oil. It is 

 used in our concrete or asphalt pavements, for roofs, for covering 

 ropes, etc. It is thought that the odor of tar has a beneficial effect 

 uj)on lung and pulmonary comi)laints, and in the winter our fragrant 

 southern forests of pine are peo})led Ijy semi-invalids, enjoying the 

 w^armth and the beauty of these places, if not always gaining perfect 

 health. 



(lum caiii]>h(H' is a concrete, volatile oil, made by distilled wood 

 with water. It is ()])tained from Formosa and Japan, from C'tnna- 

 tnoiinini cKhiplioni ^ a tree of from 30 to SO feet in height, symmetrical 

 in its foliao[e, with small, cvmose flowers. The diameter of these trees 

 is, sometimes 50 feet. The tree is cut down and hacked into chips, 

 which are placed in a still, with water on the ))ottom, and rice straw 

 on the top. In the process of vaporization, the camphor gum rises 

 and gathers in crystals on the straws. The gum is picked ofl', placed 

 in casks, and undergoes a second purification before it is read}' for 

 market. Other plants yield cam})hor, one a herbaceous composite, 

 whose gum is very volatile and pure. This is used in making India 

 ink. Borneo camphor is taken from a s})lendid tree, called J}rijo- 

 IxildiiopK <uiinj>]i(ir<i. It is described in these words. "The trunk rises 

 to the height of 130 feet, without a l)ranch, the base of which is forti- 

 fied with gigantic buttresses, and the top crowned with a cluster of 

 l)ranches clothed with large, shining leaves. Flowers showy, fragrant 

 and abundant. The canii)hor is obtained by felling the tree, cutting it 

 into lengths and then splitting it up, when the gum is exposed in layers 



