W. B. Gregory

“ The specifications under which the timber was treated were as follows:
Timber.
The timber for creosoting shall be long-leafed or southern pine. Sap surfaces on two or more sides are preferred.
[38] Piles.—The piles shall be of long-leafed or southern pine, not less than 14 in. at the butt. They shall be free from defects impairing their strength, and shall be reasonably straight.
The piles shall be cleanly peeled, no inner skin being left on them. The oil used shall be so-called creosote oil, from London, England, and shall be of a heavy quality. ”

“ In the heart wood there was very little penetration across the grain. The timber had been framed and the holes bored before treatment. The penetration of the creosote along the grain from the holes was often from 4 to 6 in.
Circular 39 of the Forest Service, U. S. Department of Agriculture, entitled "Experiments on the Strength of Treated Timber," gives the results of a great many tests of creosoted ties, principally loblolly pine, from which the following conclusions are quoted:
" ”

“ The timbers shall be subjected first to live steam superheated to from 250 to 275° Fahr., and under a 30 to 40-lb. pressure. The live steam shall be admitted into the cylinders through perforated steam pipes, and the temperature shall be obtained by using superheated steam in closed pipes in the cylinders.
The length of time this steaming shall last will depend on the size of the timbers and the length of time they have been cut. In piles and large timbers freshly cut, as long a time as 12 hours may be required. ”

“ Timbers of large and small dimensions shall not be treated in the same charge, neither shall timbers of differing stages of air seasoning, or the close-grained, be treated in the same charge with coarse or open-grained timbers. ”

“ It will be seen, however, that the treated timber 26 years old compares favorably with the new untreated timber.
Plate I, Fig. 1.—Specimen in Testing Machine, Showing Method of Support.
Plate I, Fig. 2.—End Views of Tested Timbers.
[45]
TABLE 2.—Bending Strength of Large Sticks.
Loblolly Pine. Reference number. Locality of Growth. Dimensions. Grade. Condition of seasoning. Number of tests. Moisture, per cent. Rings per inch. Specific gravity, dry. Weight per Cubic Foot, in Pounds. Fiber stress at elastic limit, in pounds per square inch. Modulus of rupture, in pounds per square inch. ”

“ Hence, it was deemed sufficiently accurate to consider the load as concentrated. Besides the horizontal bolt-holes, shown in the photographs, there were vertical bolt-holes, at intervals in all the beams. ”

“ Maximum 4,990 8,560 620 2,002 9.5 Minimum 3,110 5,160 380 1,398 5.5
Note.—Figures written as subscripts to the figures for longitudinal shear indicate the number of sticks failing in that manner.
Plate II.—Side Views of Tested Timbers.
[47]
TABLE 4.—Load and Deflection Log. Beam I.
Date: February 26th, 1909.
l = 12 ft.; b (mean) = 6-9/32 in.;
h (mean) = 15-15/16 in.;
c = 7.97 in. Time = 1 hour. Date: February 24th, 1909.
l = 12 ft.; b (mean) = 6 in.;
h (mean) = 15.69 in.;
c = 7.84 in. No. P Deflection, in Inches. P Deflection, in Inches. Load, in pounds. Reading. ”

“ Maximum 24.9 17.2 0.58 45.6 36.2 4,850 8,100 2,040 0.69 Minimum 15.0 2.7 0.41 31.2 25.6 1,730 2,910 906 0.10 4 Virginia. 8 by 8 6 to 16 Square edge Partially air dry. Average 12 22.4 4.8 0.46 35.6 28.8 3,260 5,180 1,180 0.51 0 Maximum 27.7 8.8 0.58 43.1 36.2 5,300 8,950 1,728 1.05 Minimum 17.8 2.5 0.37 30.0 23.1 1,280 2,180 606 0.13 5 Virginia. 8 by 8 6 to 15.5 Square edge Green Average 17 64.0 3.0 0.43 43.7 26.9 1,935 3,490 744 0.31 0 Very rapid growth; poor quality. Maximum 100.5 4.0 0.51 51.9 31.9 3,185 4,720 1,193 0.78 Minimum 38.8 2.5 0.35 35.0 21.9 956 2,180 357 0.12 Long-Leaf Pine. ”