Addac adding machine
1926
1926
1928
1926
1927
1934
1930
1925
circa 1927
circa 1930
1927
circa 1930
circa 1930
1931
1931
1931
1927
1925
1925
1930
1927
1926
2000-100 BCE
1928
1925-1927
1930-1931
1955; 1830
1925-1928
before 1928
1927-1929
1928
1926-1928
1990-96
circa 1927
1926
1927
1930
1925
1934
1925
1929
circa 1929
1927
1930 (replica); 1834 (original)
1926
1801-1892 (prepared); 1946 (element replaced)
1925-1930
1930
1930
1931
1928