ON WAVE MOTION. 403 



Report on Wave Motion, 



By Sir G. Greenhill, F.R.S. 



Part I. 



(Ordered by the General Committee to be printed in txtrtiso.) 



Previous Reports to be consulted are by : — 



Gerstner, Theorie der Wellen, Prague, 1804. 



Scott Russell, Report to the British Association on Waves, 1844, 



reprinted in his treatise on Naval Architecture, I., chap. xxvi. 



1865. 

 Airy, Tides and Waves, in the Encyclopcedia Metropolitana, 1848. 

 Rankine, The Trochoidal Wave, Phil. Trans. 1862. 

 W. M. Hicks, Report on Recent Progress in, Hydrodynamics. 



British Association, 1882. 

 Lamb, Wave Motion, in the Encyclopcedia Britannica. 

 0. Heavisidb, Collected Papers, III., Waves on Deep Water. 



And various mathematical papers in the Proceedings of the Royal 

 Society and the London Math. Society, by Lord Kelvin, Lord Rayleiqh, 

 BuRNsiDE, Love, Macdonald, Hough, Havelock. 



W. H. Wheeler, Tides and Waves, 19o6. 



Douglas Wilson Johnson, Shore Processes and Shore Line 

 Development. 



(These last two for fuller list of references.) 



Report on Wave Motion in Water. 



The waves may be divided into two classes : — 



1. Surface waves, visible as moving waves or rollers (Atlantic), or 

 stationary waves when seen reflected at a wall, or inside a tank, or along 

 a pier or breakwater, important in harbour design. 



2. Long flat tidal waves, propagated through the depth of the ocean, 

 not revealed except in the tide of an estuary, past the shore, as in a 

 ground swell. 



For a visible representation of actual experimental wave motion of 

 the surface of water, capable of numerical measurement, a deep rect- 

 angular tank may be employed, provided with a front wall of glass as in 



