Figure 34.—Joins of arch showing key piece, pu'e:

1, the middle piece that forms the top of the arch and acts like a key piece (pu'e), shaped so that the ulupale point at either end is on the lower and inner concave side of the piece; 2, the lango pu'e, pieces on either side of the key piece, with the ulupale points at their upper ends on the upper and outer convex sides of the pieces so as to fit against the lower ends of the key piece. Their lower ends are shaped to form the ulupale on the opposite inner concave sides; 3, the succeeding pieces are all shaped like the lango pu'e.