Note 219 — No. XXIV.
Reading edition
Ver. 80. Plato’s and Menecmus’ lore—Proclus attributes the discovery of the conic sections to Plato, but obscurely. Eratosthenes seems to adjudge it to Menecmus. “Neque Menecmeos necesse erit in cono secare ternarios.” (Vide Montucla.) From Greece they were carried to Alexandria, where (according to our author’s beautiful fiction) Rectangle either did or might learn magic.