Four scales of inches are on this two-sided, 12-inch steel rule used for engineering drawing. On one side, nine inches of one scale are divided to 1/10", one inch is divided to 1/20", one inch is divided to 1/50", and one inch is divided to 1/100". Ten inches of the other scale are divided to 1/16", one inch is divided to 1/32", and one inch is divided to 1/64". The ruler is marked: D. & B. (/) BANGOR Me. (/) U.S. Stnd. It is also engraved: W.A.L.
On the other side, ten inches of one scale are divided to 1/12", one inch is divided to 1/24", and one inch is divided to 1/48". Eleven inches of the other scale are divided to 1/14", and one inch is divided to 1/28". The ruler is engraved: W.A.L.
A farmer and sawmill owner turned toolmaker, Samuel Darling (1815–1896) apparently first made machine tools in 1846. He built a dividing engine and partnered with Edward H. Bailey in Bangor, Me., in 1852. The next year, Darling received his first patent and bought out Bailey, and by 1854 he was in partnership with Michael Schwartz of Bangor. That business lasted until Darling moved his craftsmen and equipment to Brown & Sharpe's Providence, R.I., workshop in 1866. Thus, this object was made between 1852 and 1853. For a drafting tool invented by Darling, see 1977.0460.01 and 1990.0317.02.
An unidentified relative of Erasmus Darwin Leavitt Jr. (1836–1916), the renowned American mechanical engineer and designer of steam engines, owned this rule. (None of Leavitt's children had names that began with "W," and his father's name was also Erasmus.)
References: Samuel Darling, "Apparatus for Grinding and Shaping Metals" (U.S. Patent 9,976 issued August 30, 1853); Davistown Museum, "Registry of Maine Toolmaker Listings," http://www.davistownmuseum.org/TDMtoolMakers.html; Henry Dexter Sharpe, A Measure of Perfection: The History of Brown & Sharpe (North Kingston, R.I.: Brown & Sharpe, 1949), http://www.roseantiquetools.com/id44.html.
Our collection database is a work in progress. We may update this record based on further research and review. Learn more about our approach to sharing our collection online.
If you would like to know how you can use content on this page, see the Smithsonian's Terms of Use. If you need to request an image for publication or other use, please visit Rights and Reproductions.