Archimedes determined the upper and lower range of pi by finding the perimeters of inscribed and circumscribed polygons. By doubling the number of sides of the hexagon to a 12-sided polygon, then a 24 ...

MR. H. HARBORD, who hails from Hull, has put forth three letters, with which we have been favoured. “The Circle Squared” (in November 1867) has, we guess, been noticed by Prof. De Morgan. There is a ...