suggest to be made and reported upon, and I will take pleasure in aiding to carry out the views you have expressed in regard to the protection and preservation of the works in question." The works recommended by Captain Benham for the protection of the "beach," and his estimate of the probable cost of their construction, were approved by the chief engineer on the 4th of November, 1857. The resolution of the House of Representatives is returned herewith. I am, very respectfully, your obedient servant, H. G. WRIGHT, Captain of Engineers in charge. Hon. JOHN B. FLOYD, NEW BEDFORD, MASSACHUSETTS, October 26, 1857. SIR In compliance with the instructions of the department of the 30th of September, I have, during the past week, made the examination required of the "Beach of Plymouth Harbor," and would respectfully submit the following report in relation to its present condition, with the estimate of the amount of funds which I deem necessary to be appropriated to provide for its protection, to give a reasonable certainty of its security for the future. This beach projects from the shore at the head of Plymouth bay, at about from one to two miles southeast of the town, and with a width varying from 150 to 400 feet; it continues northwards, east of, and parallel nearly to the line of shore of the central part of the town, and at about two miles distant, extending for about three miles to the channel entrance of Plymouth and Duxbury harbors. The beach, though in some places, particularly in its southern portions of gravel or "shingle," is for the most part composed of the drift sand thrown up in storms from the outer bay, and though the upper part of the harbor, protected by this beach for the southern half or two-thirds portion of its length, is available only for vessels of a smaller size, as those engaged in the coasting or fishing trade; the remaining third of this beach at the north, gives ample protection to a good anchorage for vessels of the larger class in ordinary commerce; there being, as by the representations made to me at the place, which is corroberated by the charts of the coast survey, a space of some three fourths of a mile in extent, and of ample width for vessels to swing at their cables, having a depth of fifteen feet and upwards at low water, which would be increased to twenty-five feet at high tide, which, as the bottom is good, might even make this anchorage a desirable retreat in storms for mercantile vessels of the largest class. The northern portion of this beach, which protects this anchorage, I would state, is that which appears in former years to have received the most extensive artificial protection, to which, indeed, its actual existence, (and of course this anchorage,) appears now to be due. But it not only exists, but is in very good condition, having a width as shown between high water lines on the sketc', and of this a part is covered with grass from 50 to 150 feet wide, and from 6 to 12 feet above high water line. For the greater part, this northern portion does not need any repairs or protection of consequence now, these being required only in some places of limited extent. While the remaining two-thirds south, which until recent years, from the information given me there, had remained from all tradition uninjured, high and unbroken, and with a forest growth upon it even, is now, with a general average of height in its best parts, some three or four feet lower than the greater part of the northern third, and broken up or seriously injured, through nearly its whole extent, to such a degree that there are very few parts that I feel could be relied upon as at all secure without a protection of one or the other of the kinds I have to propose for this locality. The sea at high spring tides passing over it now in different places, gives the assurance, almost, that in gales the greater portion of it might be swept away, not only into the narrow channels abreast of, or west of this part, but even into the deeper water opposite the northern part of the beach. This would leave that part as an island only, affording but little protection to the anchorage above described, even if its depth of water were not seriously diminished. The means of protection I would propose are a sort of plank box of triangular section, filled with sand, for the worst portions, which has been already found to answer a very excellent purpose here in past repairs; or for the parts requiring less defence against the sea, a simple plank fence, such as has been found very effective as a "catch sand" and beach defence near Cape Cod. The first is composed of posts of eight or ten inches in diameter, and seven to ten feet long, (according to the size of box required,) which are halved together by threes, making triangular frames, which being set up about four feet apart, with one side horizontal, are planked with two-inch plank all round, and the box is filled with sand before the planking is finished; this box being laid upon the surface at the lowest parts, or in trenches where the beach is somewhat higher. This construction, by its weight, is secure from undermining, while the sea has never been found yet to disturb its position horizontally, or to filter through. In the three or four places where it has been tried upon this beach, I found no part where it had been injured, though the sea had forced its way around the ends in some parts, as I fear, from defects in their lines of directions, or in the manner of making their terminations. The cost of this construction, as my close inquiries have led me to estimate, and which I found corroborated by the experience of the town authorities, who have executed some work of this kind on this beach, and in the most economical manner they could devise, is about $2 50 for a linear foot for boxes of ten feet on a side, and as I judge of about $2 a foot for boxes of seven or eight feet on a side, which may suffice in some parts. The plank fence I would propose to make with posts of the same size as above, set four feet apart, and four or five in the sand, and planked with two-inch plank for the remainder of the height, each post, or each alternate post being braced on the rear or inner side with oblique braces, resting in the ground or against other short posts; the expense to this construction, including the excavations. for posts, bracing, &c., I estimate at $1 per linear foot. Without giving in this report the details of each particular portion where each kind of protection is required, which I have in my notes, and which is better shown in the accompanying sketch, but which I presume might not be desired here, I would state that I have carefully gone over every part of this beach myself, for its whole extent, from the beacon on the north, to the bluffs on the hill, just below the "Clifford Hotel" on the south; that I have carefully noted the measurements, distances, &c., and used my best judgement as to the expediency of the greater or less expensive of the modes of protection, and their extent for the different places. The measurements were made with a cord, and of course are approximate, but it is not doubted are sufficiently accurate for the purposes of the estimate. The estimate of the heights and the grassed portions of the beach are for the most part, though not altogether, by the eye. The portions of the beach for which I have estimated the more efficient protection now, or the box, having frames of triangles of ten feet on a side, are altogether about 6,530 feet. I cannot, of course, say what the extent of such portions may be by the time an appropriation can be made and become available; it must, however, if changed, be greater in extent. I estimate though only for 6,530 feet, which, at $250 per foot, is $16,325. The portions, added up, for which I have thought the smaller box will suffice, are 690 feet, which, at $2 the foot, would be $1,380 additional. The parts which I have thought would be sufficiently protected by the plank fence amount, altogether, to 3,905 feet, which, at $1 the foot, would be $3,905 more; and allowing for increased injuries by another year, and for contingencies, say $390, I judge that it is not safe to estimate for less than in all twenty-two thousand dollars, which is the least sum that I could advise to be appropriated to put this beach in such conditions to render it capable of resisting, effectually, the effects of the gales in this vicinity. I would state that though the estimate, as made in detail, was put at the very lowest sum that it was thought safe or judicious to rely upon, yet I would deem it advisable that the person who might eventually superintend the work should exercise his best judgment, that if possible, as it may be in some cases, during its progress, the less expensive protection may be used if deemed prudent, to a greater extent than here estimated; that a small amount of the appropriation might be reserved for one, two, or three seasons, to repair thoroughly and without delay any possible injuries or breaches which may occur in positions entirely unexpected after the best judgment shall have been used by the engineer in deciding upon the parts needing protection. And I cannot too strongly urge, that if any appropriation is made, it should be for the whole amount necessary for this work. By this means the protection to the different parts of the beach can be given according to some general plan, and in such a way that the different constructions shall mutually strengthen and support each other, or at least not do injury to the works, or the parts of the beach adjacent, such as, I regret to say, appears to have been, to a great extent, the case in the recent constructions attempted, with insufficient means, and with the endeavor to stop existing injuries, in detached parts, without regard to the future or to any plan for the whole. The result being continued and increased injuries to the beach, such as to give me the conviction that the appropriation of any sum essentially less than that here estimated, or the appropriation and expenditure of even the whole of that sum in different years, would be a virtual throwing away of the whole amount. I need not say that the fact of this being the only harbor or anchorage, land locked from every wind, or approaching the depth of water described above, in the long stretch of coast from Boston to Cape Cod, and as I believe it is, from Cape Cod round to Long Island Sound, with the exception of the harbors of New Bedford and Newport, must make it of incalculable advantage as a refuge in cases of necessity to the shipping of the immense amount of commerce passing into Massachusetts bay, (a large portion of it coming as it does from the southward,) and must fully justify the expenditure of the sum now estimated for its protection. Very respectfully, your most obedient servant, General J. G. TOTTEN, H. W. BENHAM, Chief Engineer. |