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considered the most correct, and it may bedoubted, whether the mode of setting piles inthis way, is not preferable to the practice ofdriving them perpendicularly.

Figure 10 b, plate 10, is a section across a pile-bridge, nearly such as that described at page191, having buttresses placed above each rowof piles, to protect them from floating bodies.The lower dotted line is supposed to show theordinary water level—the upper line, that towhich the highest floods reach, 1-J foot abovewhich, the floor of the bridge should be placed.The ice breaker, or buttress, fig. 10 b, is formedof strong piles driven as deep as possible, at thedistance of about 2 feet from each other, in thedirection of their corresponding row of piles.The piles should be firmly braced together bya horizontal beam on each side, and diagonalbraces set between them. The heads, cut oft’sloping, are covered by an inclined cap-beam,the lower end of which should be 1 ^ foot belowthe water’s edge, and the upper end 2 feetabove high-water mark. The top part of thesloping cap-beam should be worked to an edge,so that any floating bodies coming upon, andforced up, as they must be by the action ofthe current, may be made to cant aside, and soturn underneath the bridge. Ice drifting upon