Page:Popular Science Monthly Volume 86.djvu/571

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WAVE WORK
567

due to an unusual disturbance of the profile of equilibrium by exceptional storms. Most of the material removed from the bar was carried seaward to perfect the proper shore profile of equilibrium demanded by the storms. Part of it, at least, should be carried back to the beach as new conditions demand a new profile. In fact, this process is already in operation, and the shore has been built so far forward in places as to obscure much of the erosive effect accomplished a few months ago. Nothing in the nature of the erosion or of the deposition indicates any change in the relative level of land and sea.

If the land were sinking at the rate of one or two feet per century, the problem of maintaining sea defenses against the ravages of the ocean in the Seabright district would be more serious than it is. The tendency of storm waves to cut into the land would be more marked than at present, and the tendency of marine forces to repair the damage by deposition during calm weather would be less evident. Even as it is the problem is sufficiently serious. Along with the alternate erosion and accretion in the shore zone, due to the varying effect of the marine forces, there is a slow loss of land resulting from the action of currents in transporting some of the eroded debris to deep, quiet waters farther out to sea. This loss can only be arrested by superior methods of artificial protection.

That the damage of which the sea is capable justifies the expenditure of large sums of money in improved sea defences is abundantly proved by the recent storms. The actual value of property completely destroyed in the single town of Seabright was enormous and the suffering of its citizens can not be estimated in money. Many who were unable to bear any loss saw the savings of a lifetime swept out to sea by the merciless waves. It would be difficult to estimate the depreciation in the value of property along this part of the coast alone, a depreciation shared by lands not actually eroded because of the apparent magnitude of the dangers to which they are subjected.

So long as the defence of the land is in a large number of hands and every landowner is practically free to do as little or as much as he pleases toward preventing the sea from gaining access to his property, many must suffer from the failure of a few to take proper precautions against marine erosion. As soon as the sea finds a point of weakness in the defences, it rapidly widens the breach and attacks adjoining property on either side. In some places where the bulkheads in front of one man's property resisted the direct attack, the property was badly damaged by erosion from one or both sides after the sea had entered neighboring lots. Some method of government supervision of marine defences would seem to be the only satisfactory solution of this serious problem.