THE WOOD 



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running from the bark toward the center, or pith. They 

 are the pith rays. If we examine the side of the board, 

 they look like broad bands if the board is quarter-sawed 

 or rift, and as short brown lines if bastard or tangent. 



^- 



bark 



FIG. 82. Alternating Spiral Grain in Cypress. (Side and end 

 view of same piece) 



When the bark was at o the grain at this point was straight. From that time 

 each year it grew more oblique in one direction, reaching a climax at a, and 

 then turned back in the opposite direction. These alternations were repeated 

 periodically, the bark sharing in these changes 



