Fixed tenon and single mortise: A tenon was shaped from the end
on one timber and inserted into the mortise of the other. When
the tenon of a large vertical timber was left unlocked, as in
masts, and sternposts, it was said to be stepped. Free tenon and
two mortises: The most common method of edge-joining planking in
ancient and early medieval vessels in the Mediterranean area, it
also was used to secure adjoining surfaces of parallel timbers,
such as stems and floor timber chocks. Corresponding mortises
were cut into each planking edge; a single hardwood tenon was
inserted into the lower plank and the adjacent plank fitted over
the protruding tenon. In many instances, the joint was locked by
driving tapered hardwood pegs into holes drilled near each
strake or timber edge. Free tenon and three or more mortises:
Used in superstructure fabrications or places where hull
planking was too narrow to provide sufficient seating for the
desired tenon length. Al through small planking joints whose
tenons are unpegged a