
Marine Timekeeper known as 'H5' by John Harrison and Son 1770
1770
1770
1744-1774
1752
1750-1760
1755
1762
1762
1769
1757
1761
1752
1762
1762
1761
1762
1762
1762
1762
1740-1760
1767
1745
1755
1750-1760
1740-1749
circa 1750
1752
1762
1750
1755
1745-1755
1745-1755
1750
1755
1762
1745-1755
1745-1755
1770
1760
2000-100 BCE
c.1750
1745
1765
1761
1705-1737
1761
1761
1762
1762
1762
1763