Watt's end measuring machine
1776
1776
1794
1760-1770
1785
1776-1780
1776-1780
1776-1780
1778
1785
1785
1769
2000-100 BCE
1782-1793
1784
1762
1762
1778
1777-1785
1782
1787
1764
hallmarked 1788
1770
1799
1796-1797
1796-1798
1775-1785
1785-1789
1783
1762
1762
1761
1761
1784
1762
1785-1790
1798
1762
1762
1797
1762
1762
1762
1781-1790
1790
1775-1795
circa 1780
1770
1775-1799 (original); 1900-1907 (model)
1797