The papers which you kindly allowed me to read before you last year consisted solely of an examination of the question whether music had a physical basis. In the course of them it was pointed out that many of the more important English text-books on harmony were more or less drafted on the lines of an affirmative answer to this question. A reference to the natural phenomena of sound, and appeals to the laws which govern the physical universe are (as was shown) the keystone of their system, and if not always obvious in the body of those works, at least form the leading idea in preface and appendix, or, if we may venture on a musical metaphor, furnish the dominant theme of both prelude and coda.