621 



ditions were in each series, provided of course, that those 

 conditions were kept constant throughout the series. 



The test for the standard timber is two minutes under a 

 steam pressure of 42*6 lbs. per square inch. In the case of 

 tests on the end of the grain, in order to decrease the 

 likelihood of error in weighing the very small amount which 

 would be abraded in two minutes, we increase the time to 

 say three or five minutes. This we can easily reduce to 

 two minutes by multiplying the result f or % as the case 

 may be. In the tests carried out six specimens of each 

 timber were tested ; two as in a (fig. 1); two as in b, and 

 two as in c, i.e., A. — parallel to direction of fibre ; B. — 

 perpendicular to direction of fibre, and also perpendicular 

 to annual rings ; C. — perpendicular to direction of fibre, 

 and also tangential to annual rings. 



