
Lowne's patent colliery air meter
circa 1880
circa 1880
1884
1940-1960
circa 1880
circa 1900
circa 1900
circa 1880
1890-1930
1950
1870-1900
1900-1930
1881
1800-1812
1920-1950
1872
1997
1997
1861-1865
1992
circa 1880
circa 1880
circa 1880
1900-1904
1997
1843
1878-1883
1965-1966
1952-55
1996
1846
1882
1986
1932