1 large wheels (20 teeth) from Charles Babbage's difference engine
1 of 3 large wheels (20 teeth) from Charles Babbage's difference engine
3 large wheels (20 teeth), spare parts and trial pieces (brass) from Charles Babbage's difference engine
1 of 3 large wheels (20 teeth) from Charles Babbage's difference engine
1 of 3 large wheels (20 teeth) from Charles Babbage's difference engine
1 of 3 large wheels (20 teeth) from Charles Babbage's difference engine
spare parts and trial pieces (brass) from Charles Babbage's difference engine