Watch how mechanical calculators perform multiplication through repeated addition and carriage shifts — the same method used for centuries
To multiply 123 × 45, the operator:
1. Sets 123 on the input levers
2. Cranks 5 times at position 0 (ones)
3. Shifts carriage left
4. Cranks 4 times at position 1 (tens)
5. Reads result: 5,535