
Marine Timekeeper known as 'H5' by John Harrison and Son 1770
1770
1770
1780-1850
1625
1640
1830
1700-1725
1690
1853
1999
1814
1924
1791
1640
1786
1800
1630
1650
1790
1794
1630
1680
1680
1675
1670
1660
1812
1680-1690
1702
1755
1690-1695
1807
1630
1690
1849
1790
1730
1700-1725
1630-85
1801-1819
circa 1801
1700
1700
1755
1700-1815
1700-1725
1680
1700-1725
1823
1650
1660