北京大学：数学物理方法：第二十二章 数学物理方程综述

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ü?? úo  
 The solitary wave, so-called because it often occurs as this single entity and is localised, was first observed by J. Scott Russell on the Edinburgh-Glasgow canal in 1834; he called it the ’great wave of translation’. Russell reported his observations to the British Association in his 1844 ’Report on Waves’ in the following words: I believe I shall best introduce the phenomenon by describing the circumstances of my own first acquaintance with it. I was observing the mo- tion of a boat which was rapidly drawn along a narrow channel by a pair of horses, when the boat suddenly stopped – not so the mass of wa- ter in the channel which it had put in motion; it accumulated round the prow of the vessel in a state of violent agitation, then suddenly leaving it behind, rolled forward with great velocity, as- suming the form of a large solitary elevation, a rounded, smooth and well-defined heap of water, which continued its course along the channel ap- parently without change of form or diminution of speed. I followed it in horseback, and overtook it still rolling on at a rate of some eight or nine miles an hour, preserving its original figure some thirty feet long and a foot and a half in height. Its height gradually diminished, and after a chase of one or two miles I lost it in the windings of the channel. `` áM?Kz ^ í ?B/á' |? ?￥ nQ^G ?o  ??C`
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