Quadratrix of Hippias

Abstract

In 430 BC, Hippias (460 BC–400 BC) of Elis (in the Peloponnese, Greece), a contemporary of Socrates, discovered the quadratrix, a curve he used for trisecting an angle. As a matter of fact, the quadratrix may be used for dividing an angle into any number of equal parts. In 350 BC Dinostratus (390BC–320BC) used the quadratrix to square the circle.¹

Dinostratus was the brother of Menaechmus (380 BC–320 BC) who is credited for having discovered that the ellipse, parabola, and hyperbola are conic sections that were later rigorously studied by Appolonius of Perga (262 BC–190 BC).