
Marine Timekeeper known as 'H5' by John Harrison and Son 1770
1770
1770
1802
1775-1785
1800
1780
1783-1800
2010
1805-1815
1879
circa 1808
1785-1795
1808
1625
1800
1630
1807
1650
1821
1796
1794
1800
1767
1740-1760
1745
1807
1792
1702
1739
1710
1999
1790
circa 1715
circa 1710
1795
1765-1775
1790
1700-1710
1907
1785-1795
1790
1730
1989-2003
1630
1650
1908
1784
circa 1840
1801-1819
1775-1800