Ribs
About fifty in number ([Figs. 91], [92]) are split with the grain (F, [Fig. 92]), so that the heart side of the wood will be on the inner side when the rib is bent. The wood bends better this way. They must be perfectly straight-grained and free from knots. Ribs for the middle are four inches wide, ribs for the ends about three inches wide ([Fig. 91] and G, [Fig. 92]), and are whittled down to a scant half an inch ([Fig. 93]). Green wood is generally used, and before it has had any time to season. The ribs may be softened by pouring hot water on them, and should be bent in pairs to prevent breaking ([Fig. 90]). They are held in shape by a band of cedar bark passed around outside.
The ribs are of importance in the shaping of the canoe. The sides bulge out ([Figs. 91], [92]). The shape of the ribs determines the depth and stability of the canoe.
Lining Strips
Other strips, an eighth of an inch thick, are carefully whittled out, with straight edges. They are a little over eight feet long, and are designed to be laid inside on the bark, edge to edge, between the bark and the ribs. These strips lap an inch or two where they meet, in the middle of the canoe, and are wider here than at the ends, owing to the greater circumference of the canoe in the middle.
Seasoning
All the timber is carefully tied up before building and laid away. The ribs are allowed to season perfectly, so that they will keep their shape and not spring back.
Fig. 92.