In southern British Columbia and in northern Washington, the ram-ended or sturgeon-nose canoes were built. These were the canoes of the Kutenai, also spelled "Kootenay," and of the Salish tribal groups. Used on rivers and lakes, they were constructed of the bark of birch, spruce, fir, white pine, or balsam, whichever was available at the building site. Wherever possible a panel of birch bark was worked in along the whole length of the gunwales. The hull form of these canoes varied somewhat, perhaps by decision of the builder, or perhaps by local tribal custom. The ends were formed with a marked "ram," the stem profiles running down and out to the "nose" in a straight or nearly straight line. In some examples the stem profiles were in a hollow curve, starting down from the gunwales rather steeply and then curving outward more gently to the nose. Most examples had a bottom that was straight or slightly hogged, while those with the hollow curve in the ram often had a slight rocker. It is believed that the intention was always to have the bottom straight but that in construction the center of the canoe lifted somewhat, thus showing a slight hog in the bottom line. The effects of loading and use on the light and flexible structure of these canoes would cause the bottom to rocker and the outboard ends to lift, thus causing the hollow in the ram profiles. These effects of loading are confirmed by tests with models of this form of canoe. The midsection was usually quite round, almost ~U~-shaped, on the bottom, but some canoes showed the bottom slightly flattened and the sides flared out somewhat. Toward the ends, the ~U~-shape became marked, and near the gunwale ends the sides of the ~U~ fell inboard slightly as they came to the gunwales, the bottom of the ~U~ having a hard turn. In plan, the gunwales approached the stems without hollow, being nearly straight or even slightly convex. The ram was long and sharp in its lower level lines and this, with the form of midsection, made this model a fast-paddling canoe, though rather unstable. Most of these canoes had but one thwart, placed at midlength, but some have been found with three thwarts and a thong tie across the gunwales, close to the stems, as well.