.MINOR PRODUCTS OF CONIFEROUS TREES. 95 



Among the minor products of coniferous trees derived either 

 directly from the resinous secretions or in combination with them, 

 the following are the most important : 



! Tar used in shipbuilding is received chiefly from the north of 

 Europe, of which the Stockholm tar of commerce is considered the best, 

 and from the United States. The distillation of tar both in America 

 and Europe (except in the south of France) was formerly, and probably 

 is still performed in a very rude manner, involving an enormous waste 

 of material. "A funnel-shaped hole is dug in a bank about six or eight 

 feet in diameter at the- upper part, and not more than about ten 

 inches at the lower. At the bottom of the hole is placed an iron 

 pan having a long pipe or spout which is made to pass through the 

 bank; the hole is then filled up with billets cut from the roots 

 and branches of Pine trees (Pinus sylvestris) which, after being- 

 kindled at the top, are covered over incompletely with turf. The 

 wood is then charred from above downwards, and the tar mixed with 

 various other products flows off at the bottom through the spout into 

 a receiver. 



Pitch is prepared by melting crude resin in iron pots over a 

 steadily increasing but at first slow fire. The melted resin is at first 

 yellow, then brown, and lastly becomes converted into black pitch. In 

 order to expedite the process and increase the output of pitch, a press 

 is used which fits in the pot and is moved downwards by a kind of 

 screw. The resin, after the pitch has been pressed out, is used for 

 making lamp-black.* 



Turpentine Paste and Pine Oil are prepared from the crude resin of 

 Pinus Pinaster. The former is much used in certain kinds of 

 varnishes, and the latter for lighting purposes ; also as an antiseptic 

 for preserving wood in the open air. 



Canada Balsam is a transparent straw-coloured resin faintly tinged 

 with green procured from the Canadian Balsam Eir, Abies balsamea; 

 it has the consistency of honey, with a pleasant aromatic odour and 

 a slightly bitter flavour. It is chiefly used for mounting objects to 

 be examined under the microscope, for which it is highly suitable, as 

 it remains constantly transparent and uncrystallised. 



Comferine is obtained from the descending sap of the Larch and 

 other trees belonging to the Fir and Pine tribe which by a chemical 

 process can be transformed into Vaiiilliiie, the aromatic principle present 

 in the fruit of Vanilla. The preparation of .Coniferine is a profitable 

 branch of industry in North Germany. 



Abietine is a volatile oil obtained from the resin secreted by some 

 of the Pines of western North America, chiefly Pinus ponderosa and 

 P. Sabiniana, and recommended for its curative virtues, which, however, 

 have been called into question by the authorities of the Philadelphia!! 

 College of Pharmacy.! 



Amber occurs chiefly in a bed four to five feet thick of glauconite, 

 geologically known as the Amber Beds of Konigsberg. It is 

 generally in small pieces, sometimes coloiirless but usually light yellow; 

 it is susceptible of a good polish, and when rubbed becomes electrical. 

 It melts when heated to 230 C., then it flames and burns with a 



* Schlich, Manual of Forestry, Vol. V. p. 169. 

 f Garden and Forest, Vol. X. (1897), p. 202. 



