Upon the keel being laid (say for a vessel of 300 tons), 1 1/4 inch oak plank is passed diagonally, at an angle of 45°, from one side under the keel up to the plank share on the other side. At the fore and after ends, from the rise of the floor, the planks cannot be passed under, and are rebated into the keel. The first planking is caulked and payed; then a second range of planking, 1 1/4 inch thick, at an angle of 45°, is laid on the first, with patent felt between, crossing the direction of the angle, and this second planking is again caulked and payed. Then the third row, 1 1/4 inch thick, is put on longitudinally, with felt between, like the ordinary planking of a vessel, and caulked and payed 1/4 inch through; bolts are used, and clenched upon ruffs such as boat-uilders use. Bent timbers are then placed inside, at every four feet apart, with small floor timbers for carrying the sleepers. The following vessels, now running upon the Thames, are built upon this plan, - Ruby, Gem, Diamond, Duchess of Kent, Topaz, Prince George, Fairy, Naiad, Ariel, and Nymph.