YIELD OF RESIN AND TURPENTINE. 728 



owing to tapping has been proved. Nordlinger showed* that 

 during the tapping, narrow-zoned and heavy wood is produced, 

 but that this wood is weak owing to the waviness of the fibres. 



The most valuable part of the resin is the oil of turpentine, 

 which is obtained from crude resin by distillation and is 

 collected in a cooling tank filled with water. The process is 

 explained in the next section. 



The percentage of oil of turpentine in the resin of different 

 trees is given below : 



Spruce, German turpentine . 20 per cent. 



[Pinus longifolia, Indian . 32 Tr.] 



Maritime pine, French ,, . 25 ,, ,, 



Austrian Austrian ,, . 25 ,, ,, 



Longleaved American ,, . 17 ,, ,, 



Larch, Venetian . 25 ,, 



Silver-fir, Strassburg ,, . 33 ,, ,, 



Tsuga, Canadian ,, . 18 ,, 



The distillation of turpentine from the wood of felled trees 

 yields only impure turpentine mixed with resin and tar. Tar 

 is made from resinous wood by dry distillation in pits or in 

 closed retorts in remote forests. [This is described at length 

 by Mathey (" Exploitation commerciale des bois.") Ordinary 

 charcoal-kilns are erected in the Landes, and the tar runs out 

 below and is collected by a channel leading into a reservoir 

 from which it can be ladled out after 60 hours burning of the 

 kiln ; it is then removed every 6 hours, the resulting charcoal 

 is light. Tr,] 



SECTION VI. EXTRACTION OF OIL OF TURPENTINE AND 

 EOSIN FROM CRUDE EESIN. t 



Casks of crude resin continue to reach the factories at La 

 Teste from March to October, the last consignments being 



* Nordlinger, " Einflosfl dcr Haming auf Wachstum u. TTolz dor Schwartz 



full Hi." IS.sl. 



f [This account is taken mainly from papers by N. Hearle and E. McA. Moir 

 in the " Indian Forester," June and July, 1895. Both these gentlemen, as well as 

 the translator, in 1894, visited a resin-factory at La Teste, near Arcachon- 

 belonging to Mr. Lesca, and all the information given in this chapter has been 

 supplied through his kindness. Mathey, op. cit., gives a more detailed ami well 

 illustrated account of the process, Tr. 



3A 2 



