: It has been years since I saw a video on one of these calculators
: so I checked out Youtube for a demo. Incredible devices!

: A link to a Curta's operation:
: https://www.youtube.com/watch?v=HYsOi6L_Pw4

This is a very cool video Mike. Thanks for digging it up. I remember my dad taking the thing apart and showing it to us kids. The thing we watch collectors might keep in mind when watching this video is that the mechanism is not unlike the column wheel found in a chronograph watch. After all, when you think about it all the Curta Calculator does is count which is the same thing a chronograph does. You can extrapolate complications such as date and even perpetual date.

Best,

JohnCote