double-end-trimmed
Descriptive of lumber which is sawn reasonably square on both ends.
A electric substation consisting of two switchboards in one common assembly, separated physically and electrically by a tie circuit breakerĀ
A doorframe which is prepared to receive two single-acting doors swinging in opposite directions, both doors being of the same
A key made of hardwood which is used to join two timbers; has a dovetail on each end which is
A pair of domes, one set within the other, both of which have the same center of curvature.