“Lieutenant Davis, U.S. Navy, suggests, ‘Hitherto we have used the English Meridian of Greenwich; all our astronomical calculations are fixed according to that, our nautical charts are adapted to it, and our chronometers are set to its time. The scientific importance of assuming an American Meridian is undoubted.’ So long as we depend upon that from which we are separated by an ocean, our absolute longitudes remain indeterminate. There is no place on our coast, the longitude of which from Greenwich is so well ascertained as Boston. Yet there still exists an uncertainty in this longitude, of perhaps two seconds of time.”

Scientific American, September 1849

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