Thomas Demilt
The Demilts (Thomas, Benjamin & Samuel) were important suppliers of nautical instruments, chronometers, and watchmaking parts and tools and operated from 156 Water Street and various addresses on Pearl Street, New York, from the late 18th century to about 1840. Reported to be the first chronometer maker in New York, Dominic Eggert worked for the Demilts starting in about 1820 and took over their business (233 Pearl Street) after Benjamin's death in 1839 (Crom, 64). 

The firm was founded by Thomas Demilt, a silversmith and watchmaker in 1796 and their agent in England for tooling and parts was the well-known Peter Stubs of Lancashire. Spittler lists a partnership with Nathaniel Hawxhurst (Hauxhurst) and a watch by Haushurst & Demilt from the late 18th century is known, as are watches by Nathaneil Hawxhurst.

This watch, from Thomas Demilt's first year of operation, is pictured in the book Horological and Other Shop Tools, by Ted Crom and was once part of Ted Crom's personal collection. Ted Crom stated, "Almost no recognition has been accorded to the Demilts of New York City. Yet they were perhaps the foremost horologists of New York City from approximately 1800 to 1845" (Crom, 60). 
Thomas Demilt Watch
Thomas Demilt Watch

Thomas Demilt
New York
Description: Fusee movement with a verge escapement and seldom seen dust ring fit around a chamfered edge on the back plate. The silver pair cases are hallmarked for London 1795-76, Demilt’s first year of operation, and has a maker mark "IG" likely, Joseph Glenny, London, with the King George III export duty mark.

Watch papers by Henry Davis of London and Sanderson of Comrie located within the watch case. Plain balance table has been riveted to the original foot, a 19th century repair.

References and recommended reading:
  • Ted Crom, Horological and Other Shop Tools 1700-1900, Florida, 1987, pp. 59-72
  • Snowden Taylor, Research Activities and News, NAWCC Watch & Clock Bulletin, No. 243 (August, 1986), pp. 310-311
  • Spittler and Bailey, Clockmakers and Watchmakers of America by Name and by Place, Columbia, PA., National Association of Watch and Clock Collectors, 2011