Addac adding machine
1926
1926
circa 1927
circa 1930
1928
1927
circa 1930
1920-1929
1920
1930
1924
1925
1928
1927
1925
1925
1921-1926
1930
1928
1922
1920-1930
1923
1924
1922-1923
1922-1923
1922-1923
1922-1923
circa 1920
1920
1955; 1830
1921-1930
1921
1925-1928
1921
1926
1924
1927
1923
1920-1929
1920-1930
1924-1927
1920-1925
circa 1930
1925-1927
1920-1925
circa 1920
1927
1926
2000-100 BCE
1920-1928
1923