Note 37 — BOOK IV.

This is a well known property of the hyperbola, and its asymptotes; and is thus expressed by Mr. Simson, in his Conic Sections, Lib. 3. Prop. 16. “If from a point in the hyperbola, any two lines are drawn to the asymptotes, and if from any point, in the same or opposite hyperbolas, there are drawn to the asymptotes other right lines parallel to the former; then the rectangle contained by the lines first drawn, shall be equal to the rectangle contained by the other drawn lines.”