Vulcan hammers appear often in geotechnical engineering textbooks and other reference material. It’s rare that it would happen outside of that discipline, but happen it did.
In 1960 the first edition of Mechanics of Materials by Archie Higdon, Edward H Ohlsen and William B. Stiles was published with the 1200A extractor photo shown above. The purpose of including it was to illustrate concentric axial stresses through the connecting links on the side from point A to point B, and specifically through the plane c-c. Vulcan granted permission to use the photo the year it left Chicago and moved to Chattanooga.
Evidently the illustration “made an impact;” it was retained through the Fourth Edition in 1985, by which time they had picked up two additional authors, John A. Weese and William F. Riley. It was in the Second Edition when this webmaster discovered it while taking Mechanics of Materials at Texas A&M in the mid-1970’s.
The 1200A had been introduced a few years before it appeared in this textbook and Vulcan went to some pretty silly lengths to publicise it. The textbook was one of the more sober ones. Below are the specifications to all of Vulcan’s extractors.
3 thoughts on “The Vulcan Extractor Photo that Made a Civil Engineering Textbook”
Bradley Sherman congress