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