On Display

    Klein bottle, 1995.

    A single surface model made by Alan Bennett in Bedford, 1995. It consists of a Klein bottle with coiled inlet tube, or jacketed coil with singularity and entrance at opposite ends, which when theoretically cut gives a pair of 19-twist Mobius strips.

     
    'Addiator' calculating machine, c 1924.

    Addiator' decimal adding machine with stylus and pencil on metal stand. Made by the Addiator-Gesellshaft Company of Berlin, Germany, the 'Addiator' was a relatively late mechanical calculator. It uses a chain mechanism, a stylus to add or subtract an

     
    Exactus stylus-operated adding and subtracting device, 1955-1965.

    Exactus stylus-operated adding and subtracting device, with swivelling half plate for add and subtract options, marked "Mini-Add Made in England", c. 1950. The Exactus is one of several simple stylus-operated calculators to have been popular in the

     
    French sector, 1751-1774.

    Brass French sector by Canivet, Paris, 1751-1774. French sectors are less complicated than English sectors. They are also used for calculations involving proportions of length, area and volume.The lines radiate from the centre of the hinge.

     
    Calculating scale, 1807.

    Ready reckoner, boxwood weighted with brass, for gross and tare weights of ship's cargoes, engraved "Robert Ludgate, Custom House, London, 1807". Tare is the weight of the packaging or container. Scales are given for finding the gross weight if the

     
    Klein bottle, 1995.

    A single surface glass vessel made by Alan Bennett in Bedford, 1995. It consists of a five-layered sphere, extension of the three Klein bottles above to infinity which when cut gives a pair of single-twist Mobius strips. A Klein bottle is a surface w

     
    Klein bottle, 1995.

    A single surface glass vessel made by Alan Bennett in Bedford, United Kingdom. It consists of three Klein bottles in a column which when cut form a pair of single-twist Mobius strips. A Klein bottle is a surface which has no edges, no outside or insi

     
    'Way-in-way-out vessel', 1995.

    A single surface model made by Alan Bennett in Bedford, 1995. This 'way-in-way-out vessel' is equivalent to two Klein bottles, one inverted, sealed together back-to-back. When cut it forms two pairs of single twist Mobius strips. A Klein bottle is a

     
    Klein bottle, 1995.

    A single surface glass vessel made by Alan Bennett in Bedford, 1995. It consists of three columns of three Klein bottles interconnected, which when cut form three pairs of single-twist Mobuis strips, one of each pair being seperate, the other of each

     
    Klein bottle, 1995.

    A single surface glass vessel made by Alan Bennett in Bedford, 1995. It consists of a five-layered sphere with added access routes which when cut produces a pair of single-twist Mobius strips. A Klein bottle is a surface which has no edges, no outsid