
Marine Timekeeper known as 'H5' by John Harrison and Son 1770
1770
1770
1781-1790
1777-1785
1760-1775
1791
1795
1775
1775
1794
circa 1750
1762
1750-1795
1798
1755
1797
1805
1800
1780
1783-1800
1795
1785-1795
1770-1800
1750-1800
1785
1776-1780
1776-1780
1776-1780
1793-1803
circa 1805
1755
1752
1750
1782-1793
1752
1770
1785-1790
1784
1750-1760
1784
1755
1762
1762
1769
1765-1806
1757
1752
1761
1762
1762
1761