carved images of the birlinn from the sixteenth century and earlier show the typical rigging: braces, forestay and backstay, shrouds (fore and aft), halyard and a parrel (a movable loop used to secure a yard or gaff to a mast). there is a rudder with pintles on the leading edge, inserted into gudgeons. it is possible that use was made of a wooden bowline or reaching spar (called a "beitass" by the norse). this was used to push the luff of the sail out into the wind.