Note 2 — LETTER LXII.
Reading edition
The difficulty is to draw it so that there shall not be the smallest portion of it which is not approaching the inner curve, and narrowing the intermediate space. And you will find no trick of compasses will draw it. Choose any number of centres you like, and still I defy you to draw the curve mechanically; it can be done only as I have done it myself, with the free hand, correcting it and correcting till I got it right.2