1912] The Naval Stokes Industry 127 



TscHiRcii's Views on Resin Flow 



As to the seat of resin production and cause of resin flow, 

 most valuable and important views have been advanced by 

 Prof. A. Tschirch in his book " Die Harze und die Harzbehal- 

 ter," 2nd edition. Tschirch has shown that the seat of resin 

 production is a mucilaginous layer lining the inner walls of 

 the resin ducts. These ducts he divides into two classes: First 

 — primary ducts, whose resin is to be considered a true physio- 

 logical product. Such ducts occur irregularly and in varying 

 number in any pine. They play only an insignificant role as 

 producers of commerical crude turpentine. Second — secondary 

 resin ducts which form in large numbers in the outer layers of 

 the new wood after a tree is wounded, both above and below the 

 wound. Their oleoresinous exudate is, therefore, a patho<- 

 logical product. It is from such pathological ducts that the 

 great bulk of crude turpentine is obtained. 



The application of these views to practical problems in the 

 turpentine forests has already yielded important and fruitful 

 results. 



Future of the Industry 



During the past few years the statement has frequently been 

 made that from present indications the naval stores industry 

 must cease to exist, at least as a large industry, within the next 

 twenty years. While it is true that there are danger signals 

 which must be heeded, such pessimistic views do not seem to be 

 well grounded. 



Certainly in France and consequently in Spain, where the 

 same system is in operation, the industry has been placed upon 

 a self-perpetuating basis. 



In America we have been prodigal with our wealth of virgin 

 forest. 



But it must be remembered that until the last decade these 

 forests have had a very low commercial valuation. The average 

 price for well timbered lands in our southern states not many 

 years ago was approximately one dollar per acre, land, timber, 

 and all. Indeed, the popular term applied to all holders of 



