British Calculator in case, with stylus and directions
Physical Object
2019.07.03.06
The British Calculator is an adding machine for British currency. It is disk-shaped, about 13.5 cm in diameter, and 9mm thick. There are three curved slots exposing part of three concentric rings. The outer ring counts ha'pennies, the middle ring counts shillings, the inner ring counts up to 49 pounds. There are numbers next to the slots, and you can insert a stylus into the slot next to a number and move the ring clockwise until you reach the end of the slot. This adds the chosen number of ha'pennies, shillings, or pounds. There are small windows to the right of the centre in which you can see the current total. The rings carry automatically, and the inner ring carries to a small wheel that counts multiples of 50 pounds.