Irish Logarithm

The Irish logarithm is a system of number manipulation invented by Percy Ludgate for multiplication in the analytical machine he designed, published in 1909 in the Scientific Proceedings of the Royal Dublin Society. Rather than relying on a full two-dimensional multiplication table, it uses mechanical cams as lookup tables together with mechanical addition, reducing multiplication of decimal digits to two single-dimensional table lookups followed by one addition, which made mechanical implementation far more practical. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/