This chronometer started life in Greenock, Scotland and ended up in the U.S. as property of the USGS. THe maker is John Heron. The shipping container and the brass bowl have the mark USGS T222173. Our Museum Director has determined that the serial number is correct for a USGS instrument. The USGS indicated that records for the use of the chronometer were sent to the Smithsonian. However, the Smithsonian can't seem to find any records. I would like to think the chronometer was used in surveys of the U.S. Does anyone have any ideas how to further this research?