BOOKREVIEW: Stevenson: German Patents and Torsion Pendulum Clocks

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Fortunat Mueller-Maerki

NAWCC Star Fellow
NAWCC Fellow
NAWCC Life Member
Sep 23, 2001
Book Review

Historical German Patents and Torsion Pendulum Clocks;
Part I, DRPs 1877-1945

By Douglas K. Stevenson

Published in 2002, Distributed through NAWCC Chapter 168, 28 Red Sabel Place, The Woodlands, TX 77380; email:; $ 12 "cost sharing" for reproduction cost and shipping. 138 pages, 8 1/2x11 inches, many illustrations.

Researching the history and the origins of torsion pendulum clocks, particularly 400-day clocks, the unsuspecting reader finds many legends and conflicting half-truths, depending if one digs into the American, British, French or German texts on the subject. The American horological enthusiast Doug Stevenson, a resident of Germany, and a regular contributor to Clocks Magazine and to the NAWCC Bulletin has now undertaken to compile purely factual source material on the subject: The 28 DRP "Full Patents" (as opposed to the DRGMs, so called "design patents") filed on the subject between 1877 and 1945 with the German Patent Office.

The full text facsimile of these 28 patents, as filed and amended, including drawings, makes up 104 pages of the book. Needless to say the patent texts are in German, so a specialized horological dictionary (like Berner, 1961, or Mauch, 1984) is very useful to fully utilize this book. This "raw" source material; is accompanied by several previously published articles by Stevenson (in English) on how to "read" and use German patent material for horological research.

This important horological research tool is being made available to the public by the author through a non-traditional publishing method: As long as the work is copied in its entirety, and on a not-for-profit basis, users may freely make copies for their own use. The NAWCC Chapter 168 has undertaken the task of distributing "seed copies" for a cost sharing contribution of $ 12 including US postage (Add $4 for overseas postage). A Copy is also available at the NAWCC lending library and may be consulted or borrowed (for copying) there at their regular lending fees.

Depending on the initial success of this novel publishing venture there is the potential of additional source material of similar nature becoming available from Stevenson in the future. The Library and Research Center (LARC) at the National Watch and Clock Museum is highly supportive of such projects, and wants to congratulate and thank Stevenson for taking this initiative.

Fortunat Mueller-Maerki. Sussex NJ
Chair, Library Committee

NAWCC Life # 174
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[This message was edited by horology on November 20, 2003 at 10:52.]

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