Abstract: | Following the recent work on wood tracheides and sisal fibres,a detailed investigation has been made of the fine structureof a wide variety of bamboo fibres. A combination of X-ray analysis,measurement of refractive indices in longitudinal view and ofphase differences in transverse section, has presented a completepicture of cellulose chain orientation. The wall of bamboo fibresis many layered. An outermost, thin layer is composed of cellulosechains making an angle of 35° to cell length and this isfollowed by other, inner layers where the angle steadily decreasesfrom outer to inner layers, first to about 20° and thento about 10°. These layers are separated by thicker layers,dark in transverse section between crossed nicols, in whichthe angle is seldom more than 56°. These are averagefigures. The results show most clearly that each angle, , varieswith the fibre length, L, in such a way that the longer cellshave steeper spirals in harmony with a relation of the typeL=A+Bcot already proposed for wood tracheides. |