Addac adding machine
1926
1926
1934
circa 1927
circa 1930
1938
1938
1928
1935
circa 1930
1937
1937
1930
1924
1928
1931
1936
1931
1925
1931
1935
1925
1930
1935
1936
1929-1935
1924
1933
1935
circa 1930
1926
1934
1927
1934
1936
1928
1924-1927
1927
1935
1935
1939
1932-1936
1934-1935
1926
2000-100 BCE
1936
1924
1925-1935
1938 and 1951
1929-1935
1927