Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: CHAPTER II THE WORK OF WAVES Advance Summary. —: Water waves, whose general characteristics were discussed in Chapter I, possess energy capable of effecting profound changes upon the margins of the land or upon artificial structures with which they may come into contact. Geologist, geographer, and engineer must each concern himself with the nature and magnitude of wave energy, and with the manner in which waves accomplish their work. The layman finds the destructive energy of waves a source of interest and wonder, and not unnaturally regards the meeting-place of land and sea as one of the most fascinating of Nature's laboratories. In the present chapter the nature of wave energy is first discussed, and the manner of wave attack upon cliffs and sloping shores is briefly treated. It is then shown that the dynamic pressures exerted by waves may be measured with reasonable exactness, and calculated and measured pressures are shown to be in substantial agreement. Some of the most striking examples of damage done by storm waves are next passed in review, in order that the reader may visualize the magnitude of the force responsible for the modification of shore features and the manifold methods of its working. In order to determine which parts of a shore or what artificial structures will suffer most from wave attack, it is essential to know precisely what factors control wave energy, and these are briefly considered. A process of "wave refraction " is shown to be responsible for the concentration of wave attack upon projecting headlands and for the comparative immunity of shores about the heads of bays. In conclusion, attention is directed to the vitally important question as to how far below the water surface wave action may be appreciable. Wave Energy. —- It can readily be s...