36 SlirhikcKje, SioelUng, Warping of Cross-gtrimed Woods 



Set H. 



In the second set of measurements, made on the radial board while 

 this was drying, vernier caUipers were employed, and the results are 

 recorded in Table H. 



During this thorough and at times rapid drying the board, in sharp 

 contrast with the tangential boards, remained flat and untwisted. 



During drying the shortening was slight, only -025 or -04 per cent. 

 o£ the maximum length, being intermediate in this respect between 

 the two tangential boards. Reverse changes in length took place, as 

 during two phases elongation took place while at the same time decrease 

 in width was marked. Especially worthy of note is the fact that 

 elongation continued to the final period of drying (June 18 to November 

 29). Such synchronous elongation and narrowing took place not only 

 during the period June 14 to 16, when the board was drying, but actually 

 continued between June 16 and 17 during a slight absorption of atmo- 

 spheric moisture. This latter fact was probably caused by the smallness 

 of the amount of the water absorbed and its incomplete distribution 

 through the wood. 



The decrease in width of the ends was 5 per cent, of the maximum 

 width, and thus less than in the tangential boards (5-92 and 6-28). 



During the process of drying, even when the board was elongating, 

 the area of the faces (as assessed by length, and width of the two ends) 

 continued to decrease. The whole decrease in area was less (40-907) 

 than in the tangential boards. 



There is evidence that soaking caused the board to increase in width 

 permanently, for the succeeding statistics show that for similar changes 

 in water-contents shrinkage in width during drying was less than 

 expansion in width during soaking. It must be noted in regard to these 

 statistics, that during soaking the width measured was not the whole 

 width of the board but the distance between two pencil points 1 1-325 

 to 12-15 cm. apart, whereas during drying the whole width of the board, 

 13-258 to 12-802 cm,, was measured. Hence for perfectly similar 

 comparison the statistics of widening given below are too small. 



