
Marine Timekeeper known as 'H5' by John Harrison and Son 1770
1770
1770
1777-1785
1744-1774
1760-1775
1775
1775
circa 1750
1762
1755
1745-1755
1745-1755
1780
1785
1776-1780
1776-1780
1776-1780
1755
1745-1755
1752
1750
1752
1770
1784
1750-1760
1784
1755
1762
1762
1769
1757
1752
1761
1762
1762
1761
1762
1762
1762
1762
1762
1786
1776
1787
1770-1780
1740-1760
1767
1745
1760
1755
1739