The plane of the joint orbit, in which no deviation from circularity has yet been detected, nearly coincides with the line of sight.
This elementary conception is of the figure as already existing, rather than of its method of description; the test of circularity being the possibility of rotation within a surrounding figure so as to keep the two boundaries always completely in contact.
As a matter of fact, no grass-plot is truly circular; and it might be found that if the breadth in various directions were measured more accurately the want of circularity would reveal itself.
How would you define circularity? Add your definition here.