Thu Own boat* Again —The three eteamer*now at the? shipyard, undergoing alterations, «jic , that they may be made gun boats, ate to be completed this week, the number of hands i employed on each vessel being ooe hundred nod fifty The interior of the hulls have ail ; been lined, tioot and aides, with two aud a | half inch oak plank, and calked perfectly 1 tight. A fore and aft bulk-head of the eame i material has also been built on each side of the hull, six feet from the aide, and cross bulkheads, tea feet apart, are to be built the whole length of the bull. Each separate apartment will be made water-tight, to prevent sinking, from any chance shot through the hull. Bulwarks eight feet in bight, have been bniltflush with the hull, from atem to etern, of the fol-; lowing material: Five iucb oak timbers, one fuot apart, have been connected to the frame : of the vessel; oak planks, of two and a half | inches in thickness have been added to these,; both inside and out. The pilot house will be | cased with the eame material as the bulkheads,; with heavy wrought iron shutters attached.I The vessels are pierced for eleven guns, placed as follows: Three guns on each aide, forward of the water wheel, and two bow guns. Two i qaarter guns abaft the wheels, and one etern I chaser gun. They will also each be provided with one heavy mortar, placed on the forward part of the bout, making in all twelve guns, some of which will be ten-inch columbiads. The boilers have been placed in the bottom of the boat, between the engiues, which leaves the decks clear for action. The guns and armaments for the vessels ure here, and will be plaoed on tiie boats on Saturday—Cm. Er[.