an army, while it is resisted in front by numbers increasing every hour from the facility of crossing any part of the intervening river-these considerations place such an enterprise in the category of extreme risks. It is quite likely to be threatened because indispensable preparations to resist it will be of an exhausting nature. This character may, however, to a great degree be taken from these preparations by a thoroughly arranged mode of action, full understanding with all likely to become participants in the defense, siple arrangements as to all things, and a steady readiness. A camp should be established near the scene of debarkation, and the troops well drilled in the first arrangements and movements of resistance. To these the local forces- that is, those drawn from the great population close at hand-will supply the first re-enforcements. Then the more distant troops summoned by telegraph will come in to assail the flanks, ad if there has been any advance, the rear of the invading column. A system of this kind well studied and thoroughly carried out may, it seems to me, be safely relied on. But in order to this all the necessary field fortifications should be begun as soon as the aspect of our political relations shall be found to be decidedly unfavorable to a peaceable adjustment. It is undoubtedly desirable to anticipate such a result by a thorough examination of the country, selection of sites, and determination of the general features at least of this defense.
Unless the health of Colonel Delafield, of the Corps of Engineers, will permit him to undertake this duty, which is hardly to be hoped, I know of no other way than to call from the engineer officers serving in the field some one of sufficient experience to take the duty in hand. This, if done, must be by getting the consent of the general commanding the Army, to whose orders all these officers are now in a particular manner subject. There is not a single officer of the corps now under orders of the Engineer Department who can be assigned to the task.
I need hardly add that among the preparations for harbor defense should be included the posting of heavy guns (all the better if rifled) at points advantageously bearing upon vessels that may have passed above the upper line of forts and batteries, so that so long as their fire can harm the city they themselves will be subject to damage. The best positions for these and their number will depend on the overplus of ordnance after the regular batteries are fully armed, unless, indeed, there be appropriated to this service from the first a special reserve of large guns, a reserve that may be applied as just satted, or be added to the strength of the field-works, according as the great attack is to be by land or water, or be divided if there are to be simultaneous attack from both quarters.
There are some other particulars of preparation within the harbor that I do not detail because of their obvious necessity, among which I might have left the obstructions by batteries or otherwise of the channel behind Staten Island through which gun- boats and other vessels of moderate draft might evade the batteries of The Narrows. But I cannot leave this great harbor and its immense interests without touching the subject of the proper mode of manning and serving the numerous guns for which the batteries are now ready. This number may be stated to be 1,000; including guns looking landward, it is even more. Allowing five men to each gun, a minimum allowance, we see a need of 5,000 men for the service of existing batteries. On this matter I cannot do better than quote from a report written by me many years ago. The words are perfectly applicable now, and while I think they
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