Page:Timber and Timber Trees, Native and Foreign.djvu/350

330 Showing the woods which have been experimented upon, arranged in numerical order of transverse strength; calculated from the formula $$\frac {lw}{4 a d^2}=S$$; the weight per cubic foot; the comparative transverse strength, English Oak being 1.000 the elasticity per formula $$\frac {l^3 w}{16 a d^3 \delta } = E$$ ; and the comparative elasticity, English Oak being =1.000 Abstracted from the tables accompanying the description of the various kinds.