![](https://coimages.sciencemuseumgroup.org.uk/74/259/large_thumbnail_1953_0353__0001_.jpg)
Stanhope square demonstrator, c.1805.
circa 1805
circa 1805
1808
1809
circa 1810
1893-4
1825
1808
1825
1806
1815
1807
2000-100 BCE
1815
1863-7
1820
1815
1802
1812
1805
1801-1823
1813
1807
1815-1825
1810-1817
1990-96
1823-1825
1808
1811-1812
1821
1824
1805-1815
1821
1815
circa 1821-1825
1809
1822
1806
1705-1737
1801
1820
1772 (original); 1919 (model)
1819
4000-2001 BCE
1801
circa 1810
1814
1801
1823-1825
1823
circa 1808