tuted for the tiebeam.
These are held partly by their pressure against each other and partly by the king or center post, and are tied to the feet of the rafters.
10 illustrates the roof-framing of the circus at Edinburgh.
It will be seen that the downward pressure is distributed upon the rafters a a and stretchers b b′, which are so tied together by straps as to bring the stress of the outward thrust ultimately upon b.
11 covers the principal apartment of the Episcopal Palace at Auxerre, France. Two sets of stays g g′ are inserted above the tie-beam, between the king-post and principal rafters; a series of curved ribs receives the ceiling plank.
12 is Norman roof; so called because it was introduced by that people into Southern Europe.
The rafters a a butt against joggles on the king-posts b b, between which braces are disposed.
13 shows in dotted lines a way by which a pointed Gothic roof was converted into a flat roof by carrying the nave walls up so as to obtain a cl