ILLUSTRATIONS. 35 



Paca 



l'ii,. ss. Relationship of different parts of same disk 340 



X!). Yield of volatile oil from constant quantity of turpentine 340 



90. Diagram of detail analyses, representing radial dimensions of test pieces in eaeh disk 344 



91. Variation of weight with height of tree 350 



92. Schematic section through stem of longleaf pine, showing variation of weight with height, diameter, 



and ago 351 



93. Variation of compression strength with moisture 353 



91. Loss of water in kiln drying and reabsorption in air, shrinking and swelling 354 



!)">. Relation of strength in compression endwise to weight of material 367 



91). Relation of weight to bending strength at rupture 368 



97. Strength of contiguous blocks, showing maximum uniformity of select quarter-sawed material in com- 



pression endwise 370 



98. Kelation of fiber stresses and distortion 373 



99. Distribution of internal stresses in a beam at rupture 373 



100. Position of neutral axis and internal stresses at rupture of beam 373 



101. Fiber distortion in unit length of beam at elastic limit 374 



102. Position of neutral plane at rupture 375 



103. Method of sawing test logs 385 



104. Apparatus for determining specific gravity 386 



105. Result of physical examination (sample) 389 



