
Marine Timekeeper known as 'H5' by John Harrison and Son 1770
1770
1770
1760-1775
1775
1775
1752
1750-1760
1755
1762
1762
1769
1757
1761
1752
1762
1762
1761
1762
1762
1762
1762
1776
1767
1755
1750-1760
circa 1750
1752
1762
1750
1755
1780
1776-1780
1776-1780
1776-1780
1750
1755
1762
1770
1770-1780
1760
1765-1775
2000-100 BCE
1778
c.1750
1776
1765
1761
1705-1737
1761
1761
1762