By Ronald Ahrens

These plans found in the Tillotson Construction Company archives show details of jack screw assembly and formwork, which were essential in the continuous pour method of building elevators, and they contain the key to unlocking the story of how screw jacks came into use.

This key in is in the all-caps lettering “FOWELL SINKS JACK AND FORM.” A Web search reveals that “Fowell” is misspelled. Russell H. Folwell and William R. Sinks were Chicagoans who were granted patent 855452 for Apparatus for Raising Concrete Forms.

The patent application, filed with drawings (seen right) on Feb. 7, 1907, and awarded on June 4, 1907, stated,  “The invention relates to means for erecting concrete structures, and more particularly to apparatus for supporting and raising the forms or molds and the staging employed in building vertical concrete walls.”

The next year, the Canadian Stewart Company Ltd., of Montreal, started building the Grand Trunk Pacific Railway’s 3.5-million-bushel terminal elevator in Thunder Bay, Ont. Folwell was chief design engineer; Sinks supervised the construction. Work was finished in 1910.

Docomomo Canada-Ontario, which is part of Docomomo International, the organization that advocates for the documentation and conservation of buildings, sites, and neighborhoods of the Modern Movement, says this:

“Folwell and Sinks experimented with their lifting device for concrete forms … in 1903-04. By the time the Grand Trunk was constructed, they had perfected their jackscrew lifting device, increased the amount of steel reinforcing and developed mechanical means for delivering the wet concrete to the construction site.”

Additionally: “The device allowed for speed in construction and resulted in smooth wall surfaces.”

The Official Gazette of the United States Patent Office, Volume 128, characterized the jack screw apparatus in a nine-point description.

Before perfecting the jack screw method, Sinks had been a proponent of tile construction for elevators, according to his grandson John Sinks, a genealogical researcher. He says his grandfather joined James Stewart & Company in 1905. For 108 years, between 1845 and 1953 (the company had come from Canada to the U.S. after the Civil War), Stewart was “one of North America’s most accomplished and longest-standing contractors,” the site of the National Building Museum tells us.  

Meanwhile, Nelson Machine Company, of Waukegan, Ill., appears to have been a manufacturer not only of screw jacks but also of pressing machines and irons.