A strong rope passing through at the cascable of a gun, used to secure it to the ship's side, and prevent it recoiling too much in time of battle, also to secure it when the ship labours; it is fixed by reeving it through a thimble stropped upon the cascable or knob at the breech of the gun; one end is rove and clinched, and the other is passed through the ring-bolt in the ship's side, and seized back. The breeching is of sufficient length to let the muzzle of the cannon come within the ship's side to be charged, or to be housed and lashed. Clinch-shackles have superseded the ring-bolts, so that guns may be instantly unshackled and shifted.