When greatly magnified, these layers appear in longitudinal sections as delicate threads without any definite arrangements, while on cross section they appear as numerous concentric strata.

This may be explained on the ground that the growth of a fibre is by successive layers which, under the influence of compression, are sheared apart.
This is particularly the case with thick-walled cells such as are found in late wood.
[Footnote 6: Jaccard, P.: Etude anatomique des bois comprimes.
Mit.d.Schw.Centralanstalt f.d.forst.

Versuchswesen.

X.Band, 1.Heft.Zurich, 1910, p.

66.] |-------------------------------------------------------| | TABLE VI | |-------------------------------------------------------| | RESULTS OF ENDWISE COMPRESSION TESTS ON SMALL CLEAR | | PIECES OF 40 WOODS IN GREEN CONDITION | | (Forest Service Cir.