Page:Timber and Timber Trees, Native and Foreign.djvu/282

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262
TIMBER AND TIMBER TREES.
[CHAP.

deck and planking purposes (for which it was judged to be especially suitable), in place of Baltic Fir and Pine timber.

It disappointed, however, the expectations of the officers, as it was soon found to shrink so excessively, that it was impossible to keep it weather or water-tight; in consequence of this it was removed from the ship. The remains of the parcel therefore passed into conversion for the most common and ordinary services, and, of the board produced, much was used for berthing in the timber sheds. It stood the test of exposure in such situations for fully eight years without showing any signs of decay, but exhibited a disposition to warp and shrink far exceeding that of any other wood in present use in carpentry.

The subjoined Table, No. CXXXIX., shows that the Russian Larch is slightly deficient in transverse strength, as compared with the Firs and Pines; but, otherwise, it is above their average.

Table CXXXIX.—Larch (Russian).
Transverse Experiments.
Number
of the
specimen.
Deflections. Total
weight
required
to break
each
piece.
Specific
gravity.
Weight
reduced
to
specific
gravity
600.
Weight
required
to break
1 square inch.
With the
apparatus
weighing
390 lbs.
After the
weight
was
removed.
At
the crisis
of
breaking.
  Inches. Inch. Inches. lbs.     lbs.
1 1.250 .150 4.50 743 688.0 648 185.75
2 1.50 .150 5.00 714 697.0 615 178.50
3 1.50 .000 475 708 645.0 658 177.00
4 1.750 .250 3.85 504 6l8.0 489 126.00
5 1.750 .150 4.15 568 647.0 527 142.00
6 1.650 .350 375 519 583.0 534 129.75
Total 9.400 1.050 26.00 3756 3878.0 3471 939.00
Average 1.566 .175 4.33 626 646.3 578 156.50

Remarks.— All broke with a moderate length of fracture.