The covering most widely used in Alaskan kayaks was the bearded seal skin and with the Aleuts the skin of the sea lion was the most popular. Throughout the eastern Arctic seal skin was the preferred covering though caribou skin was occasionally used by the caribou Eskimos in the central Arctic. The heavy, thick hides were first piled and "sweated," until the hair became loose then the skins were scraped until they were clean. They were thin and light and could be air dried and stored until ready for use. The skins had to be well soaked before being stretched over the frame of a kayak or umiak. When dried out on the boat frame they were oiled in the usual manner. It is claimed by the Eskimos that walrus skin, though strong, is not as good as the bearded seal or the sea-lion skin for boat covers, as the latter two held the oil longer and did not become water soaked as quickly as the walrus hide. The paddler's seat in most kayaks consists of a portion of heavy skin with fur attached. Sometimes this is supported by a few short, thin battens laced loosely together. These, and the fur seat sometimes are as long as the paddler's legs. No back rest is known to be used. The seat, and any batten supports, are loosely fitted and are not part of the permanent kayak structure. The kayak is usually entered by floating the boat near a stone or low bank and stepping into it with one foot, which has first been carefully wiped. With the body steadied by placing the paddle upright on the shore, or outside the kayak, the other foot is then wiped and placed in the boat. The paddler then slides downward and works his legs under the deck until he is seated with his hips jammed into the manhole rim. Getting out of a kayak is almost the reverse of this process. Great care is exercised to avoid getting dirt into a kayak, as it might chafe the hide cover. Hence the care in wiping the feet before entering. The practice of entering the boat ashore and throwing man and kayak into the water, undoubtedly very rare, is said to have been practiced not only at King Island but in some parts of Greenland. Both Alaskan and Greenland hunters often lashed two kayaks together, in order to rest in rough weather. Many kayakers using the narrow models laid the paddle athwartships across the deck to help steady the kayak when resting or throwing a weapon; this is basically the same as holding the sculls of a racing shell in the water, to steady the boat. Lashing two kayaks side by side, or parallel with spacing rods, was commonly done to enable the craft to ferry persons or cargo across streams. Some Alaskan Eskimo thus converted kayaks into catamarans and then fitted a mast and sail, but such an arrangement was never used in rough water.