George III's pendulum
1762
1762
1783
1785
1785
1748-1763
1778
1762
1769
1738-1777
1755
1735-1754.
1745-1755
1735-1752
1761
1745-1755
1761
1776
1757
1784
1762
1784
1785-1790
1762
1762
1762
1752
1752
1762
1752
1762
1755
1745-1755
1750
1735-1753
1729-1753
1720
1782
1787
1764
hallmarked 1788
1762
1762
1770
1755
circa 1750
1750-1766
1742
1785-1789
1740-1753
1720-1770