Addac adding machine
1926
1926
circa 1927
circa 1930
1928
1927
circa 1930
1930
1928
1927
1931
1931
1931
1930
1928
1924
1955; 1830
1926
1927
circa 1930
1927
1926
2000-100 BCE
1934
1930-1931
before 1928
1927-1929
1930
circa 1927
1990-96
1930
1931
1930 (replica); 1834 (original)
1926
1926
circa 1929
1801-1892 (prepared); 1946 (element replaced)
1927
1926
1929
1903 (original); 1982 (model)
1930
1830 (original); 1967 (model)
1931
1839 (original); circa 1988 (replica)
1926-1928
1928
1934
1931
4000-2001 BCE
1929