Addac adding machine
1926
1926
1926
1927
circa 1930
1932
circa 1927
circa 1930
1930
1928
1927
1924
1927
1931
1930
1934
1931
1928
1926
2000-100 BCE
1930-1931
1955; 1830
1932
before 1928
Before 1932
1931
1928
1932
1927-1929
1927
circa 1930
1930
circa 1927
1926-1928
1990-96
1929
circa 1929
1930
1927
1931
1927
1934
1926
1928
1931
1926
1929
1903 (original); 1982 (model)
1930
4000-2001 BCE
1931