THE TRAINING OF A FORESTER 



the making of charcoal and wood pulp, in 

 wood distillation, the turpentine industiy, 

 in tanning and dyeing, and in other 

 industries. 



A field of great importance is the relation 

 between the physical structure and the me- 

 chanical properties of wood. A student 

 should inform himself concerning the 

 standard methods of testing the properties 

 of stiTictural timber, by bending, compres- 

 sion, shearing, torsion, impact, and the hard- 

 ness and tension tests, with their relation to 

 heat and moisture, and the methods of sea- 

 soning, the use of preservatives, and the 

 eiFect of the rate of application of the load. 



Woods vary as to their durability. It is 

 important, therefore, to know about the 

 causes of decay, the decay-resisting power 

 of various woods, the relation of moisture 

 content to durability, why the seasoning of 

 wood is eiFective, the theory and the com- 



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