A fantastic piece of Cromford Mills history, acquired from the Arkwright Society (Charity) at Cromford Mills. It’s a German made Brunsviga Model 20 mechanical pinwheel calculating machine, serial number 220661, supplied by Block & Anderson Ltd (London & Darlington) and manufactured by Grimme, Natalis and Co. A. G., Braunschweig, Germany. I’m no mechanical calculator expert, but it appears to be functioning. The machine has great patina. This fantastic piece of social history, used in the mills offices, can be yours for £145. Collection from Chesterfield S42 7LP or I will post to a UK address, buyer to pay delivery cost.