Marine Timekeeper known as 'H5' by John Harrison and Son 1770
1770
1770
1960
1862
1913
1936
1775-1785
1785
1926
1783-1800
1705-1737
1900-1920
1825
1802
1701-1800
1941
1862
1685
1711
1799
circa 1840
1786
1795-1810
1755
1910-1936
1775
1791
1796
1776
1914-1920
1740-1760
1790
1823
1792
1788
1601-1700
1938
1700
1700-1725
1897
1899
1600
1780
1745
1784
1804
1882-1889
1950-1980
1708-1710
1792
1680