In 1874, Moses Pullen and his son William applied for a patent on a single column key adding machine in Bentham, North Yorkshire. This machine adds single digits that are input by pressing a key and then pulling the keypad. The result is read from two numbered discs, the smaller disc showing the digits from 0 to 9 and the bigger one the tens and hundreds. The highest number that the machine can show is 409.

The practicality of this machine might seem trivial to us today, but in those times, machines like this one were a big help for adding columns in accounting. Often, it was probably enough to add only the units’ position. That is why the machine got quite some attention after it was announced.

Schoolmaster Pullen and his son had started producing the calculating machine aiming at different customers. Depending on the customer’s ability to pay, they could choose between various sorts of high-grade wood for the base plate. The machine’s other components also illustrate that the aesthetics of their design played a vital part. All the mechanics are visible and thus make using the machine especially appealing.

The 3D animated video that Baris Gündogdu and Burak Celebi, both of them students of Computer Science, made as their group project in the lecture series about the history of mechanical calculating by Professor Dr. Ina Prinz shows the functionality in detail and also gives an impression of its operation and aesthetics.