
Marine Timekeeper known as 'H5' by John Harrison and Son 1770
1770
1770
circa 1750
1745-1755
1752
1762
1755
1720
1735-1752
1762
1762
1745-1755
1745-1755
1735-1754.
1752
1762
1761
1762
1762
1762
2000-100 BCE
1725-1755
1755
1752
1770
1755
1735-1753
1769
1757
1762
1762
1762
1767
1740-1760
1745
1755
1739
1745-1755
1730
c.1750
1750
1761
1750
1750-1760
1729-1753
1760
1740-1749
1750-1760
1730
1740-1753
before 1753