CHAPTER XI THE LOGARITHMIC SPIRAL

the radii Oa , Ob , etc. If we then plot, as vertical equidistant ordinates, the magnitudes Oa , Ob ... OY , and again on to Oaÿ£¢ã€ý , we obtain a diagram such as the following (Fig. 299); by {573} help of which we not only see more clearly the way in which the growth-rate varies from point to point, but we also recognise much better than before, the similar nature of the law which governs this variation