z on the other hand that each hook 14 is sectioned to comprise on its edge facing the interior of the dobby a notch 14b adapted to envelop the hub 18a of the bolt 18 or at least the pivot pin 19 thereof it will be understood that such a structure radically opposes any risk of untimely unhooking of the hook 14 with respect to the bolt 18 whatever the magnitude of the vibrations of the dobby in the course of operation and the variations which affect the efforts to which the hooks 14 are subjected during the weaving operation effectively despite the direction of offset of pin 19 with respect to the line of force y z the hook 14 is positively retained in the three orientations n s and o by the edge of notch 14b and in the fourth orientation e by the engagement of bearing face 14a against the end of the arm of the bolt in addition the reversal of the offset of pin 19 makes it possible to shorten and reduces the weight of both the hooks 14 of the dobby and the bolts 18 associated therewith as the hooks require a less marked curvature and the length of the bolts is reduced avoiding any risk of interference along path x of the tip of each hook the dimensions of the assembly are consequently reduced which is always a substantial advantage in the construction of dobbies the lightweight of the bolts and hooks makes it possible to reduce the inertia exhibited by these moving components and to increase the speed of operation of the dobby while limiting the efforts developed by the reading device for actuating the pushers.