As representing, then, the after half of this huge boom, we have the modern gaff, set at the same angle as the boom used to be; and at the foot of the sail hung on this gaff, now called a spencer or spanker, from the original inventor, we have the spanker boom, the same sort of thing as we should call the mainboom were the vessel a fore-and-aft yacht. Each mast is held in its place by stays and backstays. The stays reach from the mastheads to the centre line of the ship forward; and the backstays come down to the sides of the ship, just behind the masts. The stays and backstays are named from the mast-head from which they descend. Thus the forestay comes from the foremast-head to the bows; the foretopmast-stay from the foretopmast-head to the bowsprit-head; the foretopgallant-stay from the foretopgallant-rigging to the jibboom-head; and the foreroyal-stay from the top of the royal mast to the end of the flying-jibboom. From the bowsprit-head to the vessel's cutwater runs the bobstay, generally of chain, which takes the pull of the foretopmast-stay; and from the bowsprit-head there hangs the spar known as the dolphin-striker, to give the purchase for continuing the pull of the foretopgallant and foreroyal stays round to the cutwater; so that really all the staying starts from the hull, as does the backstay-staying. Round the lower mastheads are platforms called tops; and round the topmast-heads are skeleton platforms called crosstrees. These platforms are required not only to take the lower ends of the topmast and topgallant rigging, but also to enable the crew to strike and get up the masts and yards and work the sails. The crosstrees are fitted with outriggers pointing outward aft to enable the topgallant-backstays to give a better support to the topgallantmast than they otherwise would do. Besides stays and backstays, the masts have "shrouds" to strengthen them. The topgallant shrouds come from the head of the topgallant-rigging to the crosstrees, the topmast shrouds come from the hounds just under the crosstrees to the top, and the main, fore or mizzen shrouds, as the case may be, come from just under the tops to the vessel's side. To take the pull off the tops, the shrouds are continued round to the mast as "futtock" shrouds, on the same principle as the foretopmast-stay finds its continuation in the bobstay. The shrouds are "rattled down;" that is to say, thin lines are fastened across them to make a ladder for the men to go aloft. These lines are the "rattle-lines" or "ratlines." The foremost shroud of the lower rigging has only a "catch ratline;" that is, one ratline in about six continued to the shroud that lies furthest forward.