Canoes were always built by means of a building frame. This was made with four or five crosspieces that determined the fullness or fineness of the bottom of the canoe toward the ends. By altering the lengths of the end crosspieces, the degree of fullness in the lines of the finished canoe could be predetermined. As a result the bed, which was usually about 18 inches wider than the building frame, might have the shape of its frame marked on it twice, with two sets of holes for stakes. Otherwise, the alteration in the building frame would require a special bed to be used. In addition to the alteration in the ends of the building frame, there could also be variations in its width amidships. Christopherson's posts commonly built canoes intended for fast travel, so most of them were narrower in beam at the gunwale and across the bottom than were the fur-trade canoes of the period, and the building frame was likewise narrower. The length of the building frame used in these canoes was the same as the bottom length, or a little longer than the distance between the two headboards of the finished canoe. Thus, in a 5-fathom canoe the bottom length would be 30 feet, and in a 4½-fathom canoe, 27 feet; the beds would be some 6 feet longer than these lengths. [Illustration: Figure 139. FOREST RANGERS, LAKE TIMAGAMI, ONTARIO. (_Canadian Pacific Railway Company photo._)] As the canoes at Christopherson's were built for speed and rarely measured more than 48 inches beam between the gunwale members, the building frame was about 32 inches wide amidships, or approximately two-thirds the beam inside the gunwales in a 5-fathom canoe. The beam of his 4½-fathom canoes was less, say 42 inches inside the gunwales and 27 or 28 inches across the building frame, with a depth, bottom to top of rail cap, of between 19 and 21 inches. A 5-fathom canoe of this narrow model would carry nearly 2½ short tons with a crew of six, while the smaller model would carry nearly 2 tons. However, the capacity of a wide canoe was much greater. A 6-fathom canoe, the _Rob Roy_, built by another post about 1876 to bring in the bishop for the consecration of a church at the Lake Temiscaming post, was described by Christopherson as being about 6 feet beam on the gunwales. Considered a fine example of a freight canoe, the _Rob Roy_ was afterwards loaded with 75 bags of flour, totaling 3½ tons deadweight, and carried as well a crew of seven and their provisions and gear.