Addac adding machine
1926
1926
circa 1927
1920
1924
1925
1925
1921-1926
1924
1921
1926
1927
1934
1923
1920
1924-1927
1927
1920-1925
1922-1923
1922-1923
1922-1923
1922-1923
circa 1920
1926
2000-100 BCE
1924
1923
1927
1925
circa 1920
1922
1955; 1830
1927
1921
1923
1925-1927
1920-1925
1920
circa 1927
1920
1990-96
1920
1920
1930 (replica); 1834 (original)
1926
1924-1927
1923
1927
1922-1923
circa 1920
1922