Proceeding onwards into the sea as opportunity offers, some portion of the shoals will be removed into the shallows; another, probably, will be carried towards the cliffs. To facilitate this object, let a long tined harrow be fastened to the stern of a boat, which being urged by men, will loosen the materials on the surface of a shoal; and the flowing of the water will carry them, if the wind is in a favourable quarter, towards the shore, and thus will the beach become a consolidated body, with superabundant materials deposited at high water mark: these of course must be removed towards the cliffs. If the materials consist principally of sand, a plough might be employed with considerable advantage, turning the furrows inward towards the cliffs; on the contrary, should stones predominate, they must be deposited at the base of the cliffs. Easterly winds will remove the loose dry sand towards and fill up the spaces between them. Many suggestions, however, to expedite the work will present themselves upon inspection and trial. [70]
The distance required from one row of piles to another must also depend upon circumstances. Wherever the sea reaches in, should a shallow or flat exist, there piles will be necessary, as well as to the southward of it, which will greatly accelerate the deposition of materials where they are so much required.
Discrimination will also be necessary in the application of the piles; for a minute and continuous observer will perceive it frequently happens, the alteration of a current and the wind favouring it, the sea will reach in towards the cliffs, and undermine and excavate one locality, while another, previously visited, will become filled up by materials dislodged from the former place. [71] In the latter instance, piles will not be required to be applied immediately, for probably some of the materials, irregularly accumulated, will be requisite to be shifted to their former situation. Hence the reason of applying piles to the southward and not to the northward of a locality requiring immediate assistance.
Again, considerable difference in the insertion of the piles must be made according to the contour the beach presents; between a distance continuously flat, and a shallow that only requires to be filled up. In the latter a few piles inserted from west to east, will answer extremely well; in the former, an opposite direction must be pursued; that is, from the north-west to the south-east, according to the accompanying plate, for the sweep of the water must be taken into consideration, and also the necessity for encouraging sea-beach materials to accumulate to the southward of a groin, as well as to the northward. Upon this our final success depends.
While the above plan presents the least resistance to the tidal wave when most agitated, the tidal current will be checked and rendered powerless, and the gradual elevation, from the deposition of materials, will produce the effects exhibited by the breaking of the waves on a shelving shore; and, as they roll onwards, their power will become diminished, by wanting weight and depth to aid their motion.
In several places on this beach, the sand, shingle, &c., do not exceed four feet in depth, and in some instances are still shallower; thus at Cromer, a large body of calcareous deposition exists, and projects above the beach at low water mark; but between that and the cliffs, now temporarily protected by a sea wall, a shallow or cavity of considerable length and depth must have existed: this induced the inhabitants, who had witnessed the good the jetty had effected (previous to the injury Cromer sustained, and alluded to in a former chapter), to insert a groin immediately to the southward, or rather westward, of the town, eighty-four yards in length.
The shallow or cavity became filled up to the top of the groin, and a quantity of sea-beach material, consisting principally of sand, seemed disposed to accumulate against the base of the walls in June, 1844, but unfortunately the groin was not sufficiently extended towards the sea; the piles, instead of projecting above, did not equal in height the mound alluded to, and consequently it is not so efficacious as it would otherwise have been.
The jetty too has some influence towards prohibiting a still further proof of the efficacy of this groin, at least along shore to the northward, or rather eastward; for rude in construction, it is ill calculated to effect a twofold object, which ought to arise from it. The platform resting upon piles of huge dimensions in height and diameter, appears to have been one continuous length, from the base of the cliffs to the elevated rock at low water mark. Its considerable altitude above the surface of the beach, its unwieldy structure, from the timbers employed, and above all, its extent towards the sea being limited, accounts for its partial destruction in the storm alluded to. The dashing of the waves against the piles, even in calm weather, gives an impetus to the water at their base, and produces eddies or whirlpools, which prevent sea-beach materials accumulating in the immediate vicinity.
The inhabitants, however, appear so far to have been aware of this circumstance, that in repairing the jetty, they had recourse to iron stanchions, presenting a flat surface towards the sea; but the same impediment to utility still exists.