The Stone Jack

L.J. Kelly stone jacks

The stone jack was used to push and lift heavy loads in stone quarries, stone cutting sheds, construction sites, foundries, machine shops, and mills. They were designed to be used in a vertical, horizontal, or angled position, and to lift from the top or with a "foot lift" on the back.

The name suggests that they were originally used to lift and push blocks of stone. As industrialization progressed and the size of machinery and boilers increased, stone jacks were used to transfer these from rail car to wagon and into buildings. Stone jacks also found use in in textile mills.

Mechanically, some stone jacks are ratchets, and others use a similar design, a crank-operated rack and pinion with reduction gears. The rack and pinion are enclosed with a wood housing reinforced with iron bands. These are the only jacks made in the late 19th and 20th centuries that are part wood.

Stone jack pushing a crated boiler

E.R. Klemm of Chicago, Illinois was a leading U.S. manufacturer of stone jacks in the early 20th century. A native of Magdelburg, Germany, and a prolific inventor, Emil Richard Klemm (1859-1928) patented a steel stone jack housing that he manufactured. Klemm's business merged with Chicago hardware house J.H. Channon Corp. in 1936. Pages from 2 catalogs showing Klemm's stone jacks are on Archive.org. They are also in the 1937 Brunner & Lay catalog.

Another manufacturer of the day was L.J. Kelly of Albany, New York, who advertised his cast iron iron and steel jacks in "Granite" and other stone trade magazines.

     

Stone jacks made by E.R. Klemm of Chicago, IL, 1917