John Napier had a great deal of calculating to do. The lattice multiplication method was a big help, but he had so much to do that drawing out a lattice for every equation was cumbersome.

So he began incorporating lattice multiplication into his lessons. He was skeptical at first, but he stayed committed and soon the method “spread like a wildfire,” Rush said.

Lattice multiplication makes use of the multiplication table in order to multiply huge numbers together quickly and easily. It is thought to have originated in India and moved west into Europe.