Improvement to Lifting-Jacks (open access)

Improvement to Lifting-Jacks

Patent for the improvement of the lifting jack which allows the user to "lower the lifting bar by a step-by-step movement as well as to elevate the lifting bar by such a movement (lines 12-14). Includes instructions and illustration."
Date: January 12, 1915
Creator: Parker, Charles W. & Wittliff, Theodore H.
System: The Portal to Texas History