Addac adding machine
1926
1926
circa 1927
circa 1930
1928
circa 1930
1930
1924
1928
1931
1931
1925
1931
1925
1930
1924
1933
circa 1930
1926
1927
1934
1923
1928
1924-1927
1927
1926
2000-100 BCE
1924
1923
1927
1925
1930-1931
1932
1955; 1830
1927
1932
1933
before 1928
Before 1932
1927-1929
1923
1925-1927
1932
1925-1928
circa 1927
1933
1990-96
1930 (replica); 1834 (original)
1926
circa 1929
1924-1927