MISSOURI BOTANICAL GARDEN. 



the holes 6-8% was obtained. The soluble matter was 

 precipitated from the 2% KOH solution with dilute HC1 

 and dried at 100 C. 



WOOD BETWEEN THE ROTTED AREAS. 



The wood between the holes is darker in color than 

 the normal wood, but cannot be distinguished from it 

 structurally. Numerous fungus threads pass through the 

 walls or have punctured them in many places. Near the 

 holes much of the humus compound occurs, and many of 

 the pits show the peculiar arrangement of oil globules. 

 The specific grayity of sound heart wood and that of the 

 wood between the holes, was determined by weighing 

 blocks and measuring them. As the plates of wood 

 between the holes as a rule are but -J-J inch wide, and 

 the mass of wood not occupied by holes but ^ inch long, 

 the pieces to be measured had to be rather small. To 

 bring the two tests under similar conditions, the blocks 

 from normal wood were made of similar size. The blocks 

 were dried at 100 C. until approximately constant weight 

 was reached. The specific gravity of sound wood was 

 found to be .508; that of the other, .401. These figures 

 are probably only relatively correct, but as each is the 

 average of a number of blocks, they seem to show that 

 even if no visible change has taken place in the wood 

 between the holes, some change must have occurred, 

 otherwise there would not have been so great a difference 

 in specific gravity. Very pecky cypress planks which had 

 been exposed in lumber yards for many years, were exam- 

 ined. The powder and wood fibers which had filled the 

 holes had been washed out and had left a smooth, even 

 surface. The wood was to all intents and purposes very 

 sound, and no change except numerous perforations in the 

 walls, and the presence of much humus compound, could 

 be detected. 

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