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V. Wood to be Tested 



Woods to be tested were cut into cubes having cross, radial and 

 tangential sections taken from the nearly same part for every species 

 chosen. 



(A) A Cube measuring 4 cm was tested for its resistance in three 

 different directions. 



(B) A cube of 3 cm was varnished on 4 sides to prevent the 

 change subsequent to moisture content during the determination. Two 

 opposite sides, either cross, radial or tangential sections were left un- 

 varnished. 



VI. Relation between Electric Resistance and Quantity of 

 Moisture Content in the Wood 



The quantity of moisture contained in the wood and its distribution 

 bear a direct relation to the resistance. Thus, wood almost absolutely 

 deprived of its moisture offers high resistance to the current; and for 

 such specimen a current of 100 volts is quite inadequate to determine 

 the resistance. The resistance to electricity decreases, however, as the 

 moisture in the wood increases. That the resistance of wood to electricity 

 is directly governed by the moisture therein contained is best shown by 

 reference to Table III. Especially, careful notice shows change in 

 resistance due to variation in moisture found on the surface of wood 

 which is so easily affected by exterior physical condition. The dispropor- 

 tion of resistance to the moisture content as shown in Tables I and II, 

 is due to the change in amount of moisture on the surface of wood 

 during the experiment. Since the moisture of the surface of wood is 

 constantly influenced by the surrounding conditions, the resistance of 

 wood to electricity can hardly be determined and the figures given below 

 are only the approximate one. 



VII. Relation Existing between Direction of Wood 

 Tissues and Electric Resistance 



(1) The cross section of the wood has the least resistance (cf. 

 Tables I and II). 



