“We ourselves observed the effect of a single storm with a high tide in the night, in July, 1855. It moved the sand on the beach opposite [Highland] lighthouse to the depth of six feet, and three rods in width as far as we could see north and south, and carried it bodily off, no one knows exactly where, laying bare in one place a rock five feet high, which was invisible before, and narrowing the beach to that extent. There is usually, as I have said, no bathing on the back side of the Cape, on account of the undertow, but when we were there last the sea had three months before cast up a bar near this lighthouse, two miles long and ten rods wide, leaving a narrow cove, then a quarter of a mile long, between it and the shore, which afforded excellent bathing. This cove had from time to time been closed up as the bar travelled northward, in one instance imprisoning four or five hundred whiting and cod, which died there, and the water as often turned fresh, and finally gave place to sand. This bar, the inhabitants assured us, might be wholly removed, and the water six feet deep there in two or three days.”—p. 142. Along the eastern shores of Eastham and Orleans, the strong current of the ebb and of a portion of the flood tide sets in a southerly direction,—the undertow breaking up and carrying with it the sands from the bottom. On reaching the mouth of the Potanumaquut harbor the current, setting in, deposits this sand, thus prolonging the northern point of the entrance-way; but, acting more directly on the southern point, and aided by the retreating sea at ebb tide, the moving mass of water must necessarily cut away the southerly bank,—so that the northern point continually increasing in length and the southern point shortening, or losing material, the harbor entrance is continually travelling southward. When the Sparrow-Hawk grounded for the last time within the northern point, under the influence of a westerly gale, the sand must have rapidly accumulated about her, in the manner and from the causes we have just described. Still there would be, for a considerable time, shallow waters about her after the sand had filled in the bay nearly to her deck; and the ends of her timbers which were uppermost show at this date the rounded form which we should expect to find from a flow of waves and the attrition of the sands. But the wind is also busy on the bleak shore of the Cape; the sand is blown inward from the top of the sea line of cliffs; and in a few years from her first becoming embedded, she must have been completely submerged. Above and around her, at length the salt-marsh extended itself; but the place was well known, and the name of “Old Ship Harbor” then obtained,—nor was this name forgotten, although all knowledge of the ship itself had faded from the memory of men.