Note 508 — Chapter XI · THE LOGARITHMIC SPIRAL
Reading edition
As the successive increments evidently constitute similar figures, similarly related to the pole (P), it follows that their linear dimensions are to one another as the radii vectores drawn to similar points in them: for instance as P P1 , P P2 , which (in Fig. 264, 1) are radii vectores drawn to the points where they meet the common boundary.