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American Bridge Patents

Edited by
Emory L. Kemp
PB  978-1-933202-06-8 


American Bridge Patents: The First Century (1790-1890), thoroughly illustrated with dozens of photographs and reproductions, presents the findings of a two-decade long study of several thousand pages of patent documents collected from the U.S. Patent Office. The essays in this volume offer readers tremendous insight into the creativity that characterized the evolution of bridge patents during this important and formative period of American engineering history. Of particular interest to the authors is the great variety of innovative and unusual designs that were accommodated by the then ambiguous patent law. Alongside these case studies, authors also address the Patent Office itself, whose processes regarding permissions were reformed in 1836, linking the evolution of patent law to the technology it managed.


  • Acknowledgements
  • Preface
      Emory L. Kemp
  • Part I
  • Patents Punctuate the History of Nineteenth Century Bridge
  •   Emory L. Kemp
  • The Development of the US Patent System
  •   Shelly Birdsong Maddex
  • Discovering Technological and Engineering Histiry Through U.S. Patent Drawings: A Person View
  •   Eric N. DeLony
  • A Gallery of Patent Drawings
  • Part II
  • Researching Bridge Patents on the US Patent and Trademark Office Web Site
  •   Larry N. Sypolt
  • A List of Over Six Hundred Bridge Patents


With essays by Emory L. Kemp, Shelley Birdsong-Maddex, Eric N. Delony, and Larry N. Sypolt.

Emory L. Kemp, Professor Emeritus, West Virginia University, writes and speaks actively on historic structures and is founder and first director of the Institute for the History of Technology and Industrial Archaeology at West Virginia University. Kemp edited American Bridge Patents.

Eric N. DeLony has been at the forefront of efforts to document and preserve historic bridges under the auspices of the National Park Service.

Larry N. Sypolt, Professor of History, West Virginia University, is involved in numerous projects combining his expertise in archival work and historic preservation studies.

Shelly Birdsong-Maddex helped assemble patent records for this publication while pursuing her graduate studies at West Virginia University.


"Patents and their drawings provide a firsthand record of the development of technology. In American Bridge Patents, the reader encounters the pioneering work of some of the most creative and influential inventors of bridges that have become such a treasured part of our structural engineering history and heritage."
Henry Petroski, Duke University

"If you don't know your trusses; if you don't know a 'Fink' from a 'Linville', or the difference between a 'Pratt', a 'Howe', and a 'Whipple', then this is the book for you. It provides a glimpse into a treasury of American engineering history in the US National Archives, in the form of a collection of bridge patentees' original ink and watercolour bridge drawings."
Tom Swailes, The Institution of Structural Engineers