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My dentist had one on the reception counter a long time ago. Always fascinated me as kid.
by Lutzb 3y ago
My dentist had one on the reception counter a long time ago. Always fascinated me as kid.
- Lutzb 3y agoThere is also a wikipedia page https://en.wikipedia.org/wiki/Rolling_ball_clock https://en.wikipedia.org/wiki/Rolling_ball_clock