Grady Mullis sent this:
Mr. Possum Jim, I believe this device would have been used in a sawmill to lift beams for sawing, it would take two of the devices to lift a beam to feed a saw. I recall seeing a post and beam house here in Georgia, 12"X18" beams with mortise and tennon construction. The mechanics of this machine uses a double block pully arrangement, thereby doubling the lifting power of the device. I am guessing on what this is, but it seems logical.
From Doug F. in Canada
Have looked at this and if it is part of the barn-loom accessories, I believe it could be a press for baling the greige cloth.
The cord passes from the bottom press over the worn pulley, down, up, down and up to the windlass. The 30" height seems correct for winding and the longer foot on the one side would help resist the
torquing of the windlass.