Page:Popular Science Monthly Volume 23.djvu/553

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A NATURAL SEA-WALL.
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the well-known Farragut House. This section of the wall is by far the most symmetrical and characteristic, and is the one selected for a more detailed examination and description. Beyond this point the wall runs with occasional breaks to its northern terminus without presenting any novel features.

The annexed diagram, enlarged from measurements by the United States Coast Survey, shows that part of the wall between Fox Hill

Fig. 1.

Point and the Farragut House. It has the form of a shallow crescent, and follows high-water mark quite closely, just east of the highway. It has the general peculiarities very strongly marked, but near its northern extremity is so modified by an adjacent shoal as to give an easily-followed clew to the method of its formation. It has the three neat terraces common to the whole of the wall, and, at the time of examination, had not been marred by the walk previously mentioned. This walk was built directly along the summit, which was smoothed for this purpose, thus almost obliterating the upper terrace, and lowering the whole crest. Previously, the wall has remained substantially as originally formed, for its steepness and height were such that, as a path, it was far from alluring. But now along its landward base runs the road from Little Boar's Head to Rye Beach; the situation of this road has been materially changed by the encroachments of the sea during the last fifty years, and its old location is approximately indicated on the diagram by the dotted line.

At the highest point of the crescent near its middle the road is about twelve feet below the summit of the wall, and only four or five feet above high-water mark. Diagram number two is a cross section at this place, drawn to scale from personal measurements. The slope inward, it will be noticed, is comparatively gradual and quite regular, while the sea-face is formed in terraces, very regular and individually steep. The general seaward angle of inclination is