Section showing construction of Burroughs hand operated adding and calculating machine (non-listing) class 5 1929
Section showing construction of the earlier hand operated model of Burroughs adding and calculating machines 1929
Small trial piece for calculating machine invented by Charles Stanhope in 1777 with case, see Inv. 1872-137, probably made James Bullock. Small trial piece for calculating machine invented by Charles Stanhope in 1777 with case 1777
Stripped model of a "Curta" pocket calculating machine with cylindrical metal case Stripped model of a "Curta" pocket calculating machine with cylindrical metal case 1950-1951
Working demonstration of barrel calculating machine mechanism, constructed in Museum Working demonstration of barrel calculating machine mechanism 1978-1980