Adix mechanical adding machine.

8 x 14 x 2 cm, aluminium, kept in its original faux-leather box finished with blue velvet and satin inside.

Very first model, without the reset lever on the right. Invented by Josef Benedikt Pallweber, an Austrian watchmaker, as part of the Adix Company with partner Adolf Bordt. The Adix adding machine was born in 1903 and first patented in 1904. The machine would remain in production for the next 26 years until 1930 and was one of the most historically significant of its time. The Adix is a click-wheel column adder with nine keys. It is unique that the whole of the Adix adding machine’s mechanism is exposed so that the operator can see how the key depression, in three columns of numbers ranging from 0 to 9, is transmitted to the counting mechanism. The Adix only permits the addition of columns of individual digits and not of whole amounts. So, rather limited in its use, but faster perhaps than using your head for long sums. Depressing a key the serrated plate under it pushes to the right. The cutout under each key has a different slope, so the plate gets pushed a distance proportional to the number keyed in. The plate in turn pushes the wire rod which rotates the crank arm through an angle proportional to the key’s number. Then, when the key is released and the rod and crank move back, the cogwheel does turn with the crank, and in doing so increments the units gear of the result readout. This device was actually quite modern for its time!