This book, "The conservation and improvement of tidal rivers", by Edward Killwick Calver, is a replication of a book originally published before 1853. It has been restored by human beings, page by page, so that you may enjoy it in a form as close to the original as possible.
|Publisher:||Book on Demand Ltd.|
|Product dimensions:||5.83(w) x 8.27(h) x 0.28(d)|
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CHAPTER V. BARS THEORIES ACCOUNTING FOR THEIR FORMATION APPARENTLY DUE TO THE WAVE - STROKE NATURE OF THE OPERATION EFFECT OF THE CONFIGURATION OF THE COAST UPON THEIR EXTENT AND CHARACTER. PIERS WHY PROJECTED. CONCLUSION CLASSIFICATION OF SYSTEMS THE FACT OF HARBOUR DECAY, AND THE IMPORTANCE OF A TRUE THEORY. Strictly speaking, the consideration of the comparative powers of a tidal river and systems of improvement terminates with the last chapter; but we must not conclude without a brief reference to the outlet, and its important connection with what has already been advanced. The principal obstruction at the mouth of a tidal river is a bank or bar stretching across the entrance from point to point, and generally of a crescent shape, with less depth upon it than in the channel within it. Bars are chiefly composed of detrital matter, such as sand or small gravel, and are subject to fluctuations in height and position. They do not exist in all river outlets (though the exceptions are but few), neither are they all of the same character, the reasons for which differences will be hereafter explained. Numerous theories accounting for this feature have been propounded, but the following are most deserving of notice: Firstly. To the current from the river becoming inert at its junction with the waters of the sea, and there depositing the matter held in suspension. Secondly. To the flood and ebb streams running in different channels. Thirdly. To ground waves (flots de fond], which, during tempestuous weather, lodge sand within the entrance. . Fourthly. To a sub-marine contest between the first of the sea flood and the last of the river ebb, whereby the latter yields up the matter itholds in suspension.' Fifthly. To an insufficiency of back-water for r...