For decades, the application of trigonometric mathematics to astronomy was
held in check because of the difficulties in multiplying one sine function
by another. They didn't seem to have an easy answer; when you wanted to
know a particular number, you had to work it all out yourself. John
Napier (1550 - 1614), inventor of the logarithmic function, spent twenty
years in search of a way to put together simplified multiplication tables
for sines.

At first, he tried to calculate them by using arithmatic and geometric
progressions of large numbers. Eventually he found an incredible short
cut: by using the ratios between the numbers involved, everything
simplified beautifully. Nowadays we use calculators and computers to do
what it took John Napier (and many other mathematicians) twenty years to
figure out. A brilliant application of pure mathematics to a real world
need, Napier's logarithms expanded the mathematical tools of scientists
and engineers everywhere.

Click here to learn more about John Napier.