Page:Timber and Timber Trees, Native and Foreign.djvu/309

XXXV.] {| Transverse Experiments.—3rd Example.

(Butt to top, outer part of the tree. Fig. 32b.) of the specimen. weight required to break each piece. gravity. reduced to specific gravity 600. required to break 1 square inch. apparatus weighing 390 lbs. weight was removed. the crisis of breaking. —No. 13 broke short and split; 14, curl in the grain and broke short; 15 and 16 broke short and split; 17 and 18 broke with short fracture.
 * rowspan=2|Number
 * rowspan=2|Number
 * colspan=3|Deflections.
 * rowspan=2|Total
 * rowspan=2|Specific
 * rowspan=2|Weight
 * rowspan=2|Weight
 * With the
 * With the
 * After the
 * At
 * Inches.
 * Inch.
 * Inches.
 * lbs.
 * lbs.
 * 13
 * 1.15
 * .00
 * 3.75
 * 1035
 * 840
 * 740
 * 258.75
 * 14
 * 1.15
 * .15
 * 2.75
 * 985
 * 788
 * 725
 * 221.25
 * 15
 * 1.00
 * .00
 * 5.00
 * 1,110
 * 760
 * 876
 * 277.50
 * 16
 * 1.25
 * .15
 * 3.75
 * 920
 * 655
 * 843
 * 230.00
 * 17
 * 1.25
 * .00
 * 4.75
 * 925
 * 613
 * 905
 * 231.25
 * 18
 * 1.35
 * .20
 * 4.75
 * 845
 * 610
 * 831
 * 211.25
 * Total
 * 7.15
 * .50
 * 24.75
 * 5,820
 * 4266
 * 4920
 * 1430
 * Average
 * 1.191
 * .0833
 * 4.125
 * 970
 * 711
 * 820
 * 238.33
 * }
 * 4920
 * 1430
 * Average
 * 1.191
 * .0833
 * 4.125
 * 970
 * 711
 * 820
 * 238.33
 * }
 * }

Specimens Nos. 13 to 18, with the later layers or growth, were taken from the outside of the same plank, the object being to ascertain in the two sets of experiments—Tables CLIV. and CLV.—in which part of the length the maximum of strength lay. Table CLIV. shows that in the early layers it is in specimen 8, the second piece from the butt-end; and Table CLV. shows that in the wood of later growth it is in specimen 15, the third piece from the butt-end. We also see in the mean results of the experiments that the strength of the inner is to the outer wood as 889 :970.

Further experiments on the transverse strength of the inner and outer layers of wood of another Pitch Pine tree were then carried out, with the following results :—