As a minor point I forgot to mention yesterday, Napier's logarithm was a different function from modern logarithm but satisfies many log laws in a wary. Addit

As a minor point I forgot to mention yesterday, Napier's logarithm was a different function from modern logarithm but satisfies many log laws in a wary. Additionally the first accurate multiplication algorithm faster than long multiplication has only been devised in XX century - Karatsuba's. Abacus is just a mechanical tool that represents long addition and multiplication.