Abstract: A piston is provided to operate in a horizontally disposed cylinder, into one end of which cylinder, air may be admitted under pressure and through the other end of which cylinder, a piston rod, connected to the piston to move therewith, slidably extends to support a plurality of sprockets at the outer end of the piston rod. Additional sprockets are mounted outside the end wall of the cylinder through which the piston rod slidably extends, and a chain, one end of which is fixedly anchored near such cylinder wall, passes back and forth between and around the piston rod-supported sprockets and the stationary sprockets. The chain finally passes around a further sprocket disposed below the cylinder from which the other end of the chain then depends downwardly. The downwardly pending end of the chain may be connected with the upper end of an elongated element, the lower end of which is provided with means for attachment to an article to be hoisted. The last said element is provided with annular grooves.