Marine Timekeeper known as 'H5' by John Harrison and Son 1770
1770
1770
1690
1610; 1923
1712-1713
1769
1681
1675-1679
1701-1752
1728
1735-1745
1717-1725
1720
1700-1710
1763
1673
Made late 1700s, modified 1800s
1990-96
1654
1701-1723
1668-1672 Probable
1680
1761-1762
1705-1737
1672
1726-1728
1690-1710
1700
1675-1700
c.1750
1730-1750
1695-1702
1675-1685
1752
1700-1710
1685-1695
1650-1665
1755
1750
1708
1665-1670
1685-1695
1720
1663
1715-1725
1701-1752
1755
1650-1725
2000-100 BCE
1675-1685
1667