lated, the entire system may be kept in repair, by a very small annual expenditure. Its total cost cannot be determined at present with any great accuracy, as many of the works are not yet planned. But the conjectural estimates of the Engineer Department, made with all the care which circumstances would permit, give the aggregate cost of the whole proposed system, exclusive of those parts constructed up to 1836, about thirty-one and a half millions of dollars. This expenditure dwindles into nothingness, when compared with the additional loss which might be inflicted on the nation without it, even in one war. But its duration will be measured in centuries, if proper attention be paid to its repair, instead of the twelve years cycle, deduced from French naval statistics, as the lifetime of a man-of-war. Hence it is a fair inference that a true economy would dictate the gradual completion of this system, as fast as the means of the general government will permit. It can hardly be doubted, that when this great national work shall be finished, it will constitute a pacific argument fully competent to refute the "ultima ratio regum," thereby powerfully tending to subvert the present bloody system of international dialectics. The unity of opinion among those who have made a special study of the subject, should silence the doubts of those who question the ability of forts, to close the entrances of our harbors. Obstructions placed in the channels will detain, under their fire, any vessel attempting to pass, sufficiently long to secure her inevitable destruction, whether propelled by wind or steam. Our sea-coast batteries being all furnished with hot-shot furnaces, can, with the utmost certainty, if properly served, set fire to any wooden ship venturing within their range. If floating defences, specially adapted to harbor operations, be employed as auxiliaries, nothing but our neglect or treachery can enable a fleet to run this gauntlet with safety. Such is the decided opinion of those whom careful examination of this subject has best qualified to decide, and as this is mainly a question of facts, all vague,

careless scepticism should yield to their matured judgments.*

We have thought that the important functions of fortifications and their relations to sea-coast protection, could not better be illustrated than by a brief exposition of their application in the defence of the city and harbor of New York. The importance of placing beyond question the security of this great commercial emporium, would appear to be self-evi. dent; nor can we suppose that any person would seriously regard this object as too unimportant to justify a great expenditure. Yet, conscious as we are that the city is actually open to the approach of an invading force, which may be put on shore within seven miles of Brooklyn without disturbance from forts or storms, we confess a degree of surprise at the general apathy on this subject which has prevailed among those most concerned, during the recent agitating state of our foreign relations. It hardly seems to have been thought possible that, in the event of hostilities with England, New York should be in danger of insult. Now, we would not be alarmists, nor are we ambitious to create a sensation, but as we have bestowed a careful examination and some reflection on the facts of the case, we feel justified in stating our deliberate conviction that, in case of war with any great maritime power, New York is in greater danger of being laid under contribution and otherwise insulted, than any other city on our coast, unless its fortifications are considerably extended. This opinion is based on the fact that an enemy's inducements for such an operation against this city is so much greater than it would be for a similar enterprise elsewhere. Could he destroy the Navy-yard, with its three millions of public property, its ships on the stocks, ship materials and dry-docks, this alone would be equivalent to several victories at sea, in its effects on the progress of the war. If he were to add our mercantile marine, collected at the docks, the docks themselves, exactions of heavy contributions, or pillage of private property, he would have done us a greater injury than he could possibly have effected in any other way.

This would be Vandalism doubtless, but did the fear of that reproach stay the hand of the spoiler at Washington? Yet, great as his inducement for such a course would unquestionably be, its practicability will doubtless he denied. Prudence forbids a detailed statement of the facts which have confirmed us in the opinion that 40,000 or 50,000 men may suddenly be precipitated on the rear of Brooklyn, almost bearing the tidings of their own approach. To check such an enterprise before the apprehended mischief should be completed, would require the full force of our city troops, who could, it is to be feared, only be brought into the field in time to annoy the enemy's retreat. Certainly, full success could not be promised to such an attempt, but the injury which even its partial success might inflict on us, would be of such magnitude that all chance of such a stroke should absolutely be prevented, by availing ourselves of the facilities which, in the present case, nature has so lavishly bestowed.

There are two great water approaches to New York harbor, which must be closed against the entrance of a hostile squadron. There is an obvious advantage in closing them as far as possible from the city, as by this means we force an army attempting a bold stroke to make a longer land march, thus giving time to oppose his advance and to concentrate in force on his rear. The first position on the East River, in approaching from the Sound, capable of being occupied for this purpose, is Throg's Point, on which Fort Schuyler is now being erected. This is admirably situated on a sandy spur of the mainland, and when completed, (which will probably be in about two years,) will be almost impregnable. This, in connection with a work on Wilkin's Point, situated just opposite, would render any attempt to force this pass foolhardy in the extreme. The entrance through the Narrows is, in every sense, the most important passage on our coast. It consists of an inner and an outer harbor, connected by the Narrows, a channel of about a mile wide. The inner harbor contains Governor's, Bedlow's and Ellis' Islands, on all of which batteries are now constructed. But the strong point is at the Narrows, which is capable of being made absolutely impassable by an enemy. On the Long Island shore the present defences are in good condition and possess no inconsiderable strength. On the Sta

ten Island shore, though considerable has already been done, much more remains to be accomplished. As this is the key to the defence of New York, delay in completing its efficient occupation with permanent works, is attended with no small danger to our metropolis. The outer harbor is separated from the ocean by Sandy Hook, which is a spur of sand shooting out about five miles from the Jersey shore, across its entrance, and by a bar, with an interior line of shoals and channels, stretching thence to the Long Island shore. It contains a spacious anchorage, by the occupancy of which all ingress or egress of vessels might be prevented and a strict blockade enforced. But by occuping the point of Sandy Hook with a respectable fort, and by the erection of at most three castellated batteries on the intermediate shoals, this harbor may also be closed against an enemy, thus rendering the enforcement of a strict blockade impossible; as a hostile squadron could only maintain a blockading position when favored with calms or western or northern winds. Supposing the water approaches closed as has been indicated, a land descent can only be made by a disembarkation on the Jersey shore, on Long Island or on the northern shore of the Sound. The intersected and marshy nature of the country on the Jersey shore makes an approach to the city from that quarter quite impracticable. To effect a landing on the southern shore of Long Island would, for a similar reason, be impracticable, or at least extremely hazardous, at any point nearer than twenty miles from the city. Disembarkation on the northern shore would also be removed to about the same distance by the action of Fort Schuyler. But the western section of the island is diversified with hills and villages, which might be most efficiently employed to check the advance of an army; while the militia from the eastern portion and from the mainland, crossing at Throg's Point, might concentrate on its rear in such strength as to cut off its retreat, unless it be commenced before reaching Brooklyn. A disembarkation on the northern shore of the Sound might be made at about the same distance from the city, and would present even greater difficulties. Westchester Creek, the Bronx, Harlaem river and Harlaem heights would constitute a series of obstacles quite too great to be overcome without enormous force. From this examination it would appear to be within the power of fortifi

IT rarely happens that a man of science fills so large a space in the public eye as M. Arago; and still more rarely does it occur that the estimate made by the public in general of the merits of a savant is independent of, and in discordance with, the judgment of the world of science. Such is, however, the case with the eminent subject of this notice.

Whence arises the far-extended fame of Monsieur Arago? Whence is it that neither the name of the immortal author of the Mecanique Celeste, nor of the founder of modern Chemistry,* who fell under the revolutionary axe, nor even that of Newton himself, ever filled so many mouths, nor resounded in so many ears of contemporaries, notwithstanding the immeasurable and unquestioned superiority of their labors, and the imperishable renown which has followed their memories? The universal popularity of Arago, with all who are capable of reading throughout Europe, is sufficient to explain the exist ence of a swarm of envious detractors, who, did they possess the same ability to render their acquirements attractive to the crowd, would not scruple to resort to the same means to accomplish this which they revile in M. Arago. These persons maintain that M. Arago is a scientific charlatan on a gigantic scale, resorting to means of notoriety foreign to true science; that his reputation is spurious, and that he has arrogated a position to which nothing that he has written or discovered has given him a just title; that if it depended on M. Arago alone, physical science would have been stationary for the last half century; that with vast material means at his disposition to conduct great investigations in natural science, he has originated nothing; that, at the head of the greatest Observatory in Europe Greenwich excepted-he has not furnished to the astronomical world a single important observation; that his closet has been as barren as his Observatory; and that while his contemporaries have been exploring one great natural law after another, augmenting by their profound speculations the great store of physical

knowledge, not a single great phenomenon has been solved, not a single law of nature has been developed, in the study of M. Arago.

On the other hand, the crowd of M. Arago's admirers and partisans, which, truly speaking, includes all well-informed classes in every part of Europe, exclusive of those who by profession are devoted to the prosecution of science, boldly maintain that their idol is the first of living savans, and carrying their admiration to fanaticism, place him on a level with the greatest of names that have been registered in the archives of science.

There is a class, whose suffrage in such a case is infinitely more precious than either of these, and whose favorable verdict would exhale a more grateful perfume to this "philosopher of the people' himself than even the far-sounding applause of that multitude whose favor he has so eminently conciliated. This class is that of the high and undisputed celebrities of science; of those whose researches, discoveries and inventions have "raised them above the atmosphere of envy; whose works have already laid the vast basis of their future fame, and who look on their contemporaries with serenity, and to posterity with the security of being remembered, for the solid contributions which they have made to the general stock of human science; who are admitted to have put their shoulders effectually to the wheel, and to have advanced the human mind in its progress towards the knowledge of those laws by which the Maker of the Universe has inscribed his character on the face of Nature." What do these high and mighty intelligences say,-what do they think of the perpetual Secretary of the Institute?

That their judgment is out of all harmony with the estimate of the admiring multitude is perfectly known to every one who has moved among them, and had an opportunity of being acquainted with their sentiments. That it is in accordance with the open detractors of M. Arago and the cavilers at his popularity, is far