Chronometer Escapement Model
A Marine Chronometer commonly uses a helical hairspring rather than a typical flat, coiled hairspring. Because a chronometer had to keep accurate time amid various temperatures, this spring was extremely important. A spring that would resist temperature changes was vital for an accurate chronometer. Dr. Charles Guillaume won a Nobel Prize in physics for his development of an alloy, "Elinvar", which is unaffected by temperature changes and was non-magnetic and resisted rust. Hamilton, who made many chronometers for the U.S. Navy, adapted this alloy to create, "Hamilton Elinvar Extra", which they used for their hairsprings.
Donated by Kathleen H. Pritchard in Memory of Wilbur L. Pritchard, FNAWCC #47191 & FNAWCC #1926
1999.25.5