Patent for an improved lumber-trimmer that has "a suitable carriage or number of carriages for conveying the lumber a series of swinging frames, which carry belted saws and also supporting-wheels, which wheels, if not tripped, will ride over the lumber, carrying the saws up with them out of an operative position, but which wheels, if tripped, will ride over the lumber, but permit the suspended saws to remain in operative position to trim the lumber at different points in its length, as may be desired" (lines 23-33).