It is a work of great historical interest because it is where the symbol π appears for the first time in scientific literature to denote the ratio of a circle’s circumference to its diameter.
Jones realized that the decimal 3.141592 … never ends and that it cannot be expressed precisely.
It is thought that he chose π either because it is first letter of the word for periphery (περιφέρεια) or because it is the first letter of the word for perimeter (περίμετρος). (Or because of both).
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