About the Cover

Hammers can be used to drive nails. They can also be used to shape metal that is struck against an anvil.

In ancient times, the renowned Greek mathematician Pythagoras noticed the exceptional sounds of hammers striking anvils. He determined that the weights of different-sized hammers were proportional, with weights of 12, 9, 8, and 6 pounds. Upon further examination, he determined that the harmonious sounds were a result of the numerical relationships among the hammers’ weights and discovered a connection among numbers, ratios, and music.