Addac adding machine
1926
1926
circa 1927
circa 1930
1928
1927
circa 1930
1930
1924
1925
1928
1927
1925
1925
1930
1928
1923
1924
1955; 1830
1925-1928
1926
1924
1927
1923
1924-1927
circa 1930
1925-1927
1927
1926
2000-100 BCE
1923
1934
before 1928
1927-1929
1930
circa 1927
1925
1990-96
1930
1924
1930 (replica); 1834 (original)
1926
1926
circa 1929
1801-1892 (prepared); 1946 (element replaced)
1924-1927
1923
1923
1927
1926
1925-1930