Errata

constructionem) est ergo \( K_e \) æqualis \( KA \); unde est punctum \( K \) ad parabolam foco \( A \) & vertice principali \( C \) descriptam. \( Q.E.D. \) Bifecto autem angulo \( AKE \) à rectâ \( KB \), tanget hæc utramq; parabolam, tam foco \( F \) per \( A \) & \( K \), quam foco \( A \) per \( K \) descriptam. Unde se mutuo tangunt parabolæ. \( Q.E.D. \) Errat. Pag. 152. l. ult. pro \( \beta c. \) l. \( B b. \) FINIS. LONDON: Printed for W. and J. Innys. Printers to the Royall Society; at the Sign of the Prince's Arms, End of St. Paul's-Church-Tard.