lar to the annual rin^s aiul 



Since the harder the timber 

 abraded, we get a large number for a 

 small number for a hard timber. 



The results of the test are shown i 



1 Table I. In this 

 table the columns marked "Number" simply give the 

 number of the timber and the number of the specimen of 

 that timber, 1 and 2 being for direction of blast C 

 3 and 4 „ „ „ B 



5 and 6 „ „ „ A. 



The third, eighth and eleventh columns give the weights 

 abraded in the three directions of test. The fourth column 

 is the weight per cubic foot. The fifth column gives the 

 volume abraded H 



; and multiplied by 10 3 to make 



