Napier is relatively little known outside mathematical circles where he made what is undoubtedly an extremely important advance in the history of mathematics. Logarithms made calculations by hand much easier and thereby opened the way to many later scientific advances. His work, Mirifici Logarithmorum Canonis Descriptio, contained thirty-seven pages of explanatory matter and ninety pages of tables, which facilitated the furtherment of astronomy, dynamics and physics.
Napier's powers of invention were not exclusively confined to logarithms. He published a small treatise on a simple way to perform multiplication, the Rabdologiae, introducing a calculating device which became known as Napier's 'Rods' or 'Bones'. In an appendix he explained another method of multiplication and division using metal plates, which is one of the earliest known attempts at a mechanical means of calculation.
- MacTutor biography