PREFACE THIS book is intended for the use of students in Advanced Science Classes. It has been written with the object of giving an account of the chief points of the theory of Optics, both Geometrical and Physical, without making great demands from students in the way of Mathematical attainments. I have made some very elementary applications of the Dif ferential Calculus; but have, in general, given as well alternative methods, or have indicated how the results could be otherwise obtained; and have, I hope, by occasionally presenting the two methods of solution side by side, done something to encourage students in the use of the shorter and more elegant one. The entire book may thus be read without any more advanced knowledge of Mathematics than Higher Trigonometry. I have throughout kept in view the experimental side of the subject, and have given some account of the methods of making experiments and optical measurements, as well as indicating experiments that can be performed sometimes by very simple means in illustration of important phenomena. 303130 The majority of the illustrations have been engraved from my drawings. For others I am indebted to various books, and in particular to Glazebrook's "Physical Optics" and Jamin's "Cours de Physique." I have also to thank Messrs. Nalder Bros. and Co. for the illustration of their optical bench. LONDON, September, 1896. W. T. A. EMTAGE. |