NATURAL PHILOSOPHY FOR BEGINNERS WITH NUMEROUS EXAMPLES BY I. TODHUNTER, M.A., F.R.S. HONORARY FELLOW OF ST JOHN'S COLLEGE, CAMBRIDGE. PART II. SOUND, LIGHT, AND HEAT. London: MACMILLAN AND CO. 1877 [All Rights reserved.] PREFACE. THE present volume forms the second part of an elementary treatise on Natural Philosophy. The former part explains the Mechanical Properties of solid and fluid bodies; the present is devoted to the Secondary Mechanical Sciences, namely, Sound, Light, and Heat. These three subjects are closely connected; they all involve the idea of some medium by which mechanical action is transmitted, and all bring before us alike such important principles as reflection, refraction, and interference. Thus each subject illustrates the others, and the difficulties become much diminished by mutual comparison. All the subjects here considered have been earnestly cultivated for a long time, and consequently have been developed into a large amount of interesting facts. I have endeavoured to make a profitable selection from the quantity of material thus available; taking especially those topics which afford exercise for reasoning in explaining them, and those which admit of valuable practical applications. The examples are nearly 400 in number; they have been partly selected from published examination papers, but many of them are original. They will furnish ample exercise of the student's knowledge, and in some cases they lead by easy steps up to important general results. |