It is the resistance principally of one yarn at a time to a rupture travelling crosswise from yarn to yarn. In construction of a parachute the gores or panels are usually cut on the bias, so that the warp and filling yarns make an angle with the seams running from the centre to the hem of the parachute. In this way, if tear is started, it follows along the direction of a yarn to the seam where the resistance is sufficient to prevent further rupture.