
Synchronous motor driven timer of a type used for controlling street lighting
1940-1974
1940-1974
1997-1999
1939-1949
1930-1960
1940-1980
1970-1984
1960-1975
1940-1974
1980-1984
1904-1910
1968
1968
1968
1946
1920-1930
1920-1930
circa 1955
2020-2021
1950-1969
patented 1908
circa 1919