
Marine Timekeeper known as 'H5' by John Harrison and Son 1770
1770
1770
1777-1785
1760-1775
1775
1066; 1876
1788
circa 1750
1762
1750
1750-1795
1755
1780
1795
1785-1795
1783
1776-1780
1776-1780
1776-1780
1794
1782-1793
1762
1762
1752
1761
1762
1762
1762
1762
1781-1790
1775-1785
1785
1785
1752
1770
1785-1790
1784
1750-1760
1784
1755
1769
1757
1762
1761
1762
1762
1791
1786
1776
1787
1790