Of their ships we know a good deal both from the sagas and from the remains of actual ships preserved to us. The custom of ship-burial, i.e. burial in a ship over which a grave chamber, covered with a how or mound, was erected, was common in the Viking age, and several such ships have been discovered. The two most famous are those of Gokstad and Oseberg, both found on the shores of Christiania Fjord. The Gokstad vessel is of oak, clinker-built, with seats for sixteen pairs of rowers, and is 28 ft. long and 16 ft. broad amidships. It dates from about 900, and in form and workmanship is not surpassed by modern vessels of a similar kind. There is a mast for a single sail, and the rudder, as always in those days, is on the starboard side. The gunwale was decorated with a series of shields painted alternately black and gold. The appearance of the vessel when fully equipped can perhaps best be judged from the pictures of Viking ships to be seen in the Bayeux tapestry. There we may note the parti-coloured sail with its variegated stripes, and the rich carving of stem and stern. These magnificent sails were a source of much pride to their possessors, and the story is told of Sigurd Jerusalem-farer that on his way home from Jerusalem to Constantinople he lay for half-a-month off Cape Malea, waiting for a side wind, so that his sails might be set lengthwise along the ship and so be better seen by those standing on shore as he sailed up to Constantinople. The stem often ended in a dragon's head done over with gold, whilst the stern was frequently shaped like a dragon's tail, so that the vessel itself was often called a dragon. The Oseberg ship is of a different type. The gunwale is lower and the whole vessel is flatter and broader. It is used as the grave-chamber of a woman, and the whole appearance of the vessel, including its richly carved stem, indicates that it was used in calm waters for peaceful purposes. The story of the escape of Hárek of Thjotta through Copenhagen Sound after the battle of Helgeäa in 1018 illustrates the difference between a trading-ship and a ship of war. Hárek struck sail and mast, took down the vane, stretched a grey tent-cloth over the ship's sides, and left only a few rowers fore and aft. The rest of the crew were bidden lie flat so that they might not be seen, with the result that the Danes mistook Hárek's war-galley for a trading-vessel laden with herrings or salt and let it pass unchallenged. [Illustration: _PLATE I_ Viking ship from the Bayeux Tapestry] In the last years of the Viking period ships increased greatly both in size and number. Olaf Tryggvason's vessel, the _Long Serpent_, in which he fought his last fight at Svoldr, had thirty benches of oars, while Cnut the Great had one with sixty pairs of oars. This same king went with a fleet of some fourteen hundred vessels to the conquest of Norway.