
Marine Timekeeper known as 'H5' by John Harrison and Son 1770
1770
1770
hallmarked 1788
1795-1810
1792
1925-1935
circa 1800
1790
1850-1880
1950-1976
hallmarked 1833; 1820-1833
hallmarked 1825
1810
1912
1925
1795
1771-1800
1972
1850-1872
1800-1834
1965-1984
circa 1830
1824
1796-1816
circa 1800
1801-1830; 1871
1790-1808
1780-1790
1801-1830
1998
1950-1883
1801-1830