The mechanism of the Thales A pinwheel calculator

The Thales model A is an early mechanical calculator that uses a pinwheel mechanism of the standard Odhner design. In this video I demonstrate this mechanism. In my other video I show how the machine is used normally.    • The Thales model A calculator   For more information on this machine and other mechanical calculators in my collection, please visit my website: https://www.jaapsch.net/mechcalc/ 0:00 Introduction 0:24 Carriage 2:22 Clearing mechanism 2:59 Crank cycle 5:30 Input pins 6:03 Carry mechanism 7:46 Counter mechanism 8:08 Latch 9:45 Outro