312 UNITED STATES FOREST POLICY 



In connection with the studies in wood preservation, experiments 

 are conducted in the protection of wood from destruction by decay, 

 fire abrasion, and insects; the cost and efficiency of preservatives, 

 various processes of preservation, and the suitability of different 

 species to preservation. This includes experiments in the preservation 

 of wood blocks for paving, carried on in cooperation with various 

 cities ; experiments in the preservation of railroad ties and telephone 

 poles, carried on in cooperation with railroad companies, and tele- 

 phone and telegraph companies ; experiments in the preservation of 

 mine timbers, carried on in cooperation with mining companies ; tests 

 in the prevention of wood decay in cotton factories, where conditions 

 are very favorable to decay, carried on in cooperation with factory 

 owners and insurance companies ; experiments in devising a preserva- 

 tive for wooden ships against marine borers ; tests in the methods of 

 preserving fence posts and silo timbers from decay; a great number 

 and variety of tests and experiments vitally related to the commercial 

 interests of the country. 



Experiments in the kiln-drying of lumber have been carried on for 

 some time, and it is claimed that these experiments have resulted in 

 much more economical drying of some woods. In the drying of red 

 gum, for instance, one of the most difficult and refractory woods to 

 dry, it is claimed that commercial losses' have been reduced from 15 

 per cent to less than 1 per cent. So in the drying of maple shoe lasts, 

 the period required has been reduced from nearly two years to seven 

 weeks. A method was perfected recently whereby hemlock ship lap 

 was dried in forty to forty-eight hours, two-inch planks in four to 

 six days. Some interesting experiments in kiln-drying have been 

 carried on in cooperation with furniture companies, woodenware 

 manufacturers, lumber manufacturers and railroads. 



Studies of derived products cover a vastly increasing field, includ- 

 ing investigations in the manufacture of pulp and paper, to ascertain 

 the fitness of various woods for paper making, the process appro- 

 priate to different woods, the possibility of using waste barks for 

 the manufacture of pulp and paper products, the latter investigations 

 being carried on in cooperation with paper companies. In this class 

 of investigations are included also those relating to wood distilla- 

 tion — the extraction of acetate of lime, wood alcohol, rosin, turpen- 



