Addac adding machine
1926
1926
1926
1927
1938
1938
1938
1935
1938
circa 1930
1936
1934
1929-1935
1937
1937
1938
1938
1932
circa 1938
1935
circa 1927
circa 1930
1930
1935
1928
1927
1924
1934
1927
1936
1931
1930
1934
1938
1936
1931
1934
1928
1935
1926
2000-100 BCE
1936
1938 and 1951
1929-1935
1937-1938
1930-1931
1935
1937-1937
1935
1955; 1830
1937-1938