TRANSOMS, in a ship, certain beams or timbers extended across the stern-post of a ship, to fortify her after-part, and give it the figure most suitable to the service for which she is calculated.—Transoms are here defined beams or timbers, because they partake equally of the form and purpose of those pieces. Thus the deck-transom is the aftmost or hindmost beam of the lower deck, whereon all the deck-planks are rabbeted: and all the transoms are fixed athwart the stern-post, in the same manner as the floor-timbers are laid upon the keel. As the floor-timbers also, with regard to their general form and arrangement, have a rising, by which the bottom becomes narrower as it ascends towards the extremities; so the arms of the transoms, being gradually closer in proportion to their distance from the wing-transom downwards, give a similar figure to that part of the ship, which accordingly becomes extremely narrow, from the counter towards the keel; and this general figure or curve is called the flight of the transoms.—Although these pieces are therefore extremely different in their figures, according to the extent of the angles formed by their branches or horns, each of them has nevertheless a double curve, which is partly vertical and partly horizontal, with regard to its situation in the ship. The former of these is called by the artificers the round-up, and the latter the round-ast.—As the transoms fill up the whole space comprehended between the head of the stern-post above and the aftmost floor-timbers below, it is necessary to distinguish them by particular names. Thus the highest is called the wing-transom; the next, the deck-transom; and afterwards follow the first, second, and third transoms; together with the intermediate ones.—The vertical direction of the arms or angles of the transoms, with regard to the ship's length, are expressed in the plane of Elevation, and their horizontal curves are also delineated on the plane of Projection. See SHIP-Building.—The highest transoms are connected to the ship's quarter by knees, which are bolted to those pieces and to the after-timbers.