A new experimental technique is presented that allows the direct observation of fibre deformation during wet pressing. Pulp fibres were wet pressed onto a glass slide and the region where two fibres crossed was examined microscopically through the glass. While the underlying fibre was in contact with the glass slide down its length, the overlying fibre must span from the top of the fibre to the glass slide. The geometry of the intersection is controlled by both the local conformability of the overlying fibre and the deformability of the underlying fibre. It is not primarily con-
trolled by the longitudinal flexibility of a fibre. The method provides new opportunities to investigate the effect of mechanical and chemical treatment on the papermaking properties of pulp
fibres in both the dry and wet state.