Farey's ellipsograph dated 1817 in mahogany case. An ellipsograph is used to draw ellipses, which consist of a combination of two circular motions. The drawing pencil is fixed in position in a central ring, which then revolves. At the same time, the
Brical' adding machine in case with two bone styluses. Patented by H and M Dickinson, the 'Brical' was Britain's answer to the French circular 'Tronset' instrument and is a modification of it. It was designed to add sums of money from 1/2d to £500.
A single surface model made by Alan Bennett in Bedford, 1995. It is a Klein bottle which has been cut to form two single-twist Mobius strips. A Klein bottle is a surface which has no edges, no outside or inside and cannot be properly constructed in t
Napier's bones, cylindrical arrangement in wooden box with ten figured rollers; inside lid inscribed "This box was the identical property of the author of ye Logs, Napier 1824" from the library of the Lord Napier and Ettrick. This type of Napier's b
A single surface glass vessel made by Alan Bennett in Bedford, 1995. Its form is a variation on the Klein bottle with an inlet passing through the vessel which when cut forms a pair of single-twist Mobius strips. A Klein bottle is a surface which has
Little Professor' calculator, children's working educational toy / game, 1980. Electronic calculators were now low cost available items which could be targetted at children and those with straightforward requirements. This example was exhibited in th
Ready reckoner giving the value of discounts of 10%, 15% and 20% on quantities between 15 and 36. This was probably a one-off instrument for use in a particular shop or workshop.
Harding's improved counter by Harding, Richardson, Rhodes and Co. Ltd., Leeds. Revolution counters were devised to keep a record of the operation of machinery.
Numeric Demonstrator', an elementary teaching aid patented by Ethel Linay in about 1900.. This elementary arithmetical teaching apparatus consists of ten wooden rods with squared paper pasted on them in order to show multiplication visually.
S & N adding machine by Seidel & Naumann, Dresden, serial no. 2398, in fitted box with stylus and instructions. The Seidel and Naumann adding machines used chain drives and a stylus. The numbers to be added were pulled down to the base bar and then a