BOLTS, in gunnery, are of several sorts; as, 1. Transum-bolts, that go between the cheeks of a gun carriage, to strengthen the transums. 2. Prise bolts; the large knobs of iron on the cheeks of a carriage, which keep the hand-spike from sliding, when it is poizing up the breech of a piece. 3. Traverse bolts; the two short bolts, that, being put one in each end of a mortar carriage, serve to traverse her. 4. Bracket-bolts; the bolts that go through the cheeks of a mortar, and by the help of quoins keep her fixed at the given elevation. And, 5. Bed-bolts; the four bolts that fasten the brackets of a mortar to the bed.