The Officer of the boat gives the order—
"PIVOT ON THE PORT (OR STARBOARD) BOW!"
29. No. 7, with the assistance of the others, trains the rear end of the slide into the bow-pivot which is not to be used. No. 2 bolts it in. No. 3 draws bolt out of stem-pivot, and, with assistance, draws round the forward end of the slide into the pivot to be used; drops in the bolt. No. 2 withdraws the bolt from rear end of slide.
The sweep on the bow-pivots includes an arc of about 120 degrees.
It is not advisable to train the howitzer more than a point abaft the beam if forward, or more than a point forward the beam if aft; as the accidental explosion of a shell near the muzzle, and even of a shrapnel, might be dangerous to those in the boat.
On the bow-pivot, the piece may be pointed nearly from the direction of the keel to a little abaft the beam.
SHIFTING THE HOWITZER.
30. If the howitzer does not bear on the object with such assistance as is admissible from the helm, then the Officer in command may direct it to be shifted to the other end of the boat.
The light 12-pounders, with their boat-carriages, average 660 pounds each; and can be transported by hand from one end of the boat to another.
With their boat-carriages, the 12-pounders of 750 average 1,200 pounds each; the 24-pounders about 2,000 pounds, and will probably be more conveniently managed, especially if the boat has motion, by placing rollers 2-1/2 to 2-3/4 inches in diameter on the tracks laid for the field-carriage. On these the boat-carriage can be shifted from one end of the boat to the other, using light falls to keep it under command.