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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1874 Excerpt:...for Reductive Power--Cellular Structure for reducing Waves--Stilling Basin--Situations for unprotected Quays--Booms--Small Harbours--Capacity of Commercial and of Fishing Harbours. In laying out the general design or ground-plan of a harbour, the principal matters to be kept in view are the proper disposition of the lines of the piers, so as to insure safe and easy ingress and egress, and the inclosure and protection of a sheet of water of sufficient depth. The positions in which the piers are to be placed depend on the nature and configuration of the shore and of the bottom. Before any step can be taken, the engineer must have before him numerous and accurate soundings, so as to give a correct representation of the bottom. The means of obtaining such data come strictly within the range of marine surveying, and I will not therefore enter at all upon the subject of these preliminary investigations, but shall leave the reader to consult those works which are specially devoted to this branch of surveying Vide D. Stevenson's "Marine Surveying:" Edinburgh, 1842. After a correct plan, with soundings, has been obtained, the next step is to lay down contour lines of the different depths, which make the limits of the deep and shoal water at once obvious to the eye. The lines of the piers may then be sketched, so as, without sacrificing other conditions, to keep the works as much as possible on the shoal ground, while they at the same time inclose the greatest possible amount of deep water. General Rules.--Many points requiring great care, for they affect vitally the ultimate success of the whole scheme, now present themselves for particular study. Among the most prominent of these--for we cannot take cognisance of all the peculiarities and the difficulties...