The ribs Christopherson called "timbers" and the sheathing, "lathing." The ribs, commonly of cedar, were usually ¼ to ⅜ inch thick, and were 2½ to 3¼ inches wide in most canoes, with a long taper so that near the ends the width was about half that at the middle, and at the ends they tapered almost to a point. Some large canoes had ribs 4 inches wide at the centerline, amidships, but these appear to have been unusual. The ribs were placed on the building frame at their proposed position and the width of the frame at that point was marked on each. After being cut to about the required length and tapered, the ribs were then treated with hot water, and were then usually bent over the knee in pairs, the marks determining where the bending was to be done. In a freight canoe the ribs amidships would be nearly flat across the bottom but in a fast canoe they would be slightly rounded. The parts of the rib nearest the ends were not bent, and thus the rib would appear dish-shaped when in form. Each pair while drying was sometimes held by cords tied across the ends, or the ribs might be inserted in about their proper location in the unfinished canoe and held in place by battens and struts until they took their final set. The ribs at the extreme ends were often "sprung" or "broken" at the centerline to get the ~V~-section required there, particularly in a sharp-ended express canoe. [Illustration: Figure 140 FUR-TRADE CANOE STEM-PIECES, models made by Adney: 1, Algonkin type; 2, Iroquois type, Ottawa River, old French; 3, Christopherson's canoes.] The sheathing was about ¼-inch thick and was laid according to the tribal practice of the builder; Christopherson appears to have followed the Algonkin practices generally in this as in other building matters at his posts. Whereas Malecite practice was to lash the bark cover to both inwale and outwale, in the western type of canoe the cover was lashed to the main gunwale first, owing to the spread gunwales, and the outwale was then pegged to the gunwale and also lashed, the ends being wrapped with figure-eight turns. All gunwale lashing in fur-trade canoes was in groups. Because of the sheer at the ends, the outwales were split horizontally into four or more laminae, and the splitting extended almost to the end-thwart positions. In a few canoes outwales were omitted or were short and did not extend beyond the end thwarts, but this practice was relatively uncommon. The outwales were usually rectangular in cross section and much tapered toward the ends.