Saw this lovely, if slightly knacked, adding machine in the Sun Inn, in Morpeth. You stick a stylus (or a finger) in one of the holes and drag it down to add to a column. It was a bit rusty and skipped digits more often than not.
@ColinTheMathmo no, it does it for you. There must be something like a notch on the side of each digit drum, to catch the next one along. The columns you pull down are on springs, too.
I've got a Correntator, which I think is the (old-) money equivalent of your addiator
A Mastodon instance for maths people. The kind of people who make \(\pi z^2 \times a\) jokes.
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