Chapter VIII.

On page 40 of my Memoir on the Danger and defences of New York City was given a fair and accurate exposition of the entire system of the fortifications of that city, including not only the works already built, but of those in progress, and those that had merely been projected by boards of engineers or the Engineer Bureau. The fourth and fifth points of that exposition, relating to the defence of new york and Brooklyn from land attacks, were on the next page stated to be the sole themes designed to be discussed in that memoir; and the consideration of the other points was stated to be avoided for the time. The essential and inherent defects of the system of channel fortification as practiced at New York, (as one of the places fortified according to the designs of the Engineer Bureau,) and the accidental faults which exist on the works on the approaches to that harbor, considered as channel defences, were not touched upon in that memoir.

II.

The general objections which that system is open to, have been discussed at great length in my "New Plan for the Fortifications of Certain Points of the Sea-coast of the United States,"* and it will be sufficient to refer to it such readers as may choose to investigate the validity of the following conclusions in regard to such system, which I quote from page 74, and following of said memoir:

"The first objection I offer to the existing system is with respect to the size. It adopts, even in localities where there is plenty of room† different sort of masonry casemated castles, of the smallest are that will hold the number of guns required, in from two to five tiers; the guns firing through embrasures in the scarp wall, which is exposed to its base, or nearly so, to the fire of flotillas. This remark applies to the sea fronts of all our sea-coast forts of importance. (Those not on this principle are small, and situated in localities where one sort of work will answer as well as another.) The works referred to have, in some cases, land front; that is, fronts which do not bear on the approaches of ships, or on anchorage ground. These are arranged sometimes on the bastion system, sometimes on the German; but in all cases are contracted ‡ and weak, owing to the difficulty§ of joining strong land fronts to casemated sea fronts of small development.

"The small area of these works will prevent them, in the first place, from holding any more ammunition and stores than they will need if exposed to protracted bombardment. As to a siege, those which are out of reach of help, such as Key West, Fort Point, Ship Island, and Pensacola, will probably be short of supplies very soon, and be reduced from that cause. There will be, in no case, the interior space required to accommodate the magazines, &c., which must be located and protected, at the points specified, and where the plan of fortification is still to be decided upon.

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* For Ship Island a work is projected, or at least its plan and dimensions have been decided on by a board of engineers, which may be described as follows:

It is in the form of a horseshoe, the circular portion fronting towards three points of the compass, while the gorge, which forms what may be called the land front, looks towards the fourth.

This tower or castle has, on the circular part, one tier of sea-coast guns in casemates, firing through embrasures in the masonry scarp, and one tier of barbette guns. This circular part is entirely devoid of flanking arrangements.

The gorge of the work is equal in extent to the diameter of the circle, (which I forget, but which is rather to be counted in feet than yards,) and is also of masonry, and flanked by howitzers alone, or with the assistance of a few loopholes.

† At Key West, Ship Island, Fort Point, Pensacola, the site of Fort Tompkins, and Fort Richmond, at Sandy Hook, Fort Adams, and other places.

‡ Without any exception, they are smaller than a Vauban front.

§ In illustration of this see Forts Adams and Schuyler, in each of which two sides of the main work are flanked by flanking casemates in the outworks. This arrangement is certainly open to criticism, but I mention it only to show that it has been found difficult to connect the sea and land fronts; and I wish it to be understood that I do not find fault with the plan of these works, but only object to this plan being followed hereafter, now that it appears to be unsuitable to circumstances that have arisen since they were built.

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