The Tercentenary of π

The use of the Greek letter π to denote the ratio of the circumference of a circle to its diameter appears to have been popularised by Euler following his adoption of the symbol in 1737 and later in his many popular textbooks. The original use of the symbol for this purpose was in fact by the Welsh mathematician William Jones who used it his book Synopsis Palmariorum Matheseos published in 1706. This book was described in 1824, over a hundred years later as follows ‘This work has long been esteemed as a compendious, but comprehensive summary of Mathematical Science’.