![](https://coimages.sciencemuseumgroup.org.uk/73/973/large_thumbnail_1923_0159__0001_.jpg)
Reason slot meter, c.1920.
1918-1922
1918-1922
1918
1920
1917
1919
1918
circa 1920
1921
2000-100 BCE
1922
1921
1917-1918
1934
circa 1920
1920
1955; 1830
1918-1920
1918
1918
1917
1920
1920
1990-96
1920
1920
1930 (replica); 1834 (original)
circa 1920
1839 (original); circa 1988 (replica)
1919
4000-2001 BCE
circa 1920
circa 1919
1922
1934
1920-1922
1917
1921
1922
1903 (original); 1982 (model)
1772 (original); 1919 (model)
1918-1920
1917-1918
circa 1917
1830 (original); 1967 (model)
1918
1801-1892 (prepared); 1946 (element replaced)
c. 1922
circa 1922
circa 1920
circa 1922