Page:Timber and Timber Trees, Native and Foreign.djvu/79

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to be of better quality than those referred to in Table VII. The following are the results :—

Table XIV.
Tensile Experiments.

Number of the specimen.	Dimensions of each piece.			Specific gravity.	Weight the pieces broke with.	Direct cohesion on 1 square inch.
	Inches.				lbs.	lbs.
43	$\scriptstyle {\left.{\begin{matrix}\ \\\\\ \\\ \\\ \\\ \\\ \\\ \ \end{matrix}}\right\}\,}$	2×2×30	$\scriptstyle {\left\{{\begin{matrix}\ \\\\\ \\\ \\\ \\\ \\\ \\\ \ \end{matrix}}\right.}$	1003	35,560	8,890
44				1005	31,360	7,840
45				1002	33,600	8,400
46				905	33,040	8,260
47				720	24,640	6,160
48				725	23,520	5,880
Total	...			5360	181,720	45,430
Average	...			893	30,287	7,571

Very little appears to be known of the amount of resistance offered by British Oak to a crushing force, when applied in the direction of its fibres. Some experiments of the kind have, it is true, been made, both in this and in other countries, but the results, as published, are far from being satisfactory, inasmuch as they vary to a great extent, as between author and author, and afford no reliable measure of the strain to which a pillar or column can be safely loaded.

The difficulty of carrying out these experiments is indeed so great, and withal so extremely tedious, that it is no matter of surprise more has not been done in this direction. I have, therefore, with the view of supplying a want long felt, availed myself of every opportunity to extend this important inquiry, by experimenting not only upon English Oak timber, but upon perhaps a greater variety of woods than has ever before been attempted.