
Marine Timekeeper known as 'H5' by John Harrison and Son 1770
1770
1770
1781-1790
1777-1785
1791
1795
1775
1775
1794
1798
1797
1800
1780
1783-1800
1795
1785-1795
1770-1800
1785
1776-1780
1776-1780
1776-1780
1782-1793
1770
1785-1790
1784
1784
1769
1791
1786
1800
1776
1787
1770-1780
1790
1796
1794
1800
1800
1767
1800
1792
1795
1800
1790
1795
1795
1775-1800
1790
1792
1792
1790