Those roads, therefore, render a siege to any of the works of defence before those places out of the question.

To lay siege to any place along our sea-front involves not only the disembarking of an army, but the landing also of the siege-train. This requires time.

From the time that the head of our invading column jumped out of the boats, up to their waists in the water, at Vera Cruz, till General Scott was ready to send his summons to the city, was thirteen days, and it was four days more before his heavy artillery drew overtures from the besieged-total, seventeen days.

Imagine an army, the best equipped it may be the world ever saw, that should attempt to beleaguer one of our strongholds for seventeen days. Within that time we could bring against him, by railroads and steamboats, millions of the freemen, which this country ever holds in reserve, to fight its battles. It might be Boston, before which this imaginary army is supposed to set down in imaginary siege, or it may be New York, Philadelphia, Norfolk, Charleston, or New Orleans-it is immaterial where. In less than half the Vera Cruz time we could throw millions of men into any one of these places, and subsist them, in the meantime, by a daily market train of cars and steamboats, catering for them in the abundant markets of the Mississippi valley.

It is impossible that any army, however brave, spirited, and daring, should ever think of invading a country like this, and attacking us upon our own ground, when we have under our command such powers of concentration and such force in reserve as twenty millions of freemen, the electric telegraph, the railroad car, the locomotive, and the steamboat.

The present system of fortifying the coast is founded on the principle of making the fortifications "strong in proportion to the value of the great objects to be secured.”*

This is the principle upon which every system of national defence must rest; and as to this principle itself there can be no difference of opinion. The ques tion is, in what shall the strength of a fortification consist? For a fortification that is strong against the most powerful weapons and modes of attack known to our age may be weak before those that the inventions and improvements of another age may call forth.

In the feudal times castles were built to enable those within to withstand the attack of spearsmen and archers. These old castles were strong in their day, but in ours they are impotent and of no avail.

The fortifications of 1816 were built to withstand the armaments which were mounted upon the ships of that day; and what were they?

In 1812 the Duke of Wellington, when preparing to besiege Badajos, wrote to Admiral Berkley, commanding the Lisbon station, to request the loan of twenty twenty-four pounders from the fleet. Admiral Berkley, in reply to the request for twenty-four pounders, stated that no ship under his command carried guns of so heavy a nature; but offered to supply twenty eighteen pounders, with carriages and ammunition complete. It would be difficult to find now-adays any ship in any fleet with guns so small as a twenty-four pounder.

Now it has been proven, or made probable, that it is practicable to put on board ships, carry to sea with safety, and manage with effect, long guns with a calibre for shot of one hundred and thirty-five pounds at least; and it would be as reasonable to expect a fortification which was built to resist shot of eighteen or twenty-four, or even of thirty-two or forty-two pounds, to withstand the concussion of shot of one hundred and thirty-five pounds weight as it would be to

See report of the board of army officers, 1840, on the millitary defences of the country—a paper that is drawn with great ability, and to which I shall occasionally refer. It is contained in Pub. Doc. No. 206, House of Reps., 1st session 26th Congress.

†Journal of Sieges in Spain and Portugal, vol. 1, p. 145.

expect a thirty-two pounder to strike harmlessly against a wall which was built only to resist a ten pound shot.

In 1816 our fortifications had to be provided with the means of withstanding sieges. Hence, they were required to be as strong in the rear as in the front, and to be equally invulnerable from every direction. But now steam and electricity render our seaboard fortifications invulnerable in the rear and protect them against sieges. Attempts to carry by storm may be made; but as for an enemy who sees and understands, as the leader of every army must see and understand, the powers of concentration which steam gives us as for such an enemy to think of setting down before one of our strongholds and proceeding regularly to invest it, by executing parallels, building fascines, digging trenches, throwing up enbankments, making approaches and the like, it is out of the question. Our railroads perfectly protect the entire coast line from Maine to Georgia from any such attempt. We may be blockaded by sea, and harassed from ships, but we cannot be beleagured on the land.

These are the changes which have rendered necessary a change in the whole system of national defence, and the chief stationary works of defence which we now want along the Atlantic seaboard, are those that will protect our cities and towns from the great guns of big ships.

We may admit, in imagination, now, a dashing enemy again into the Chesapeake; we may suppose him landed, with all his forces, and to be, without opposition, in the act of taking up his line of march again for this city.

Now, is it not obvious-supposing the country to be in a reasonable state of preparation at the commencement of war-supposing this much, is it not obvious, by sending telegraphic messages, and using the powers of steam for conveyance, the American general might sit down here, in Washington, and at daylight the next morning commence an attack upon that enemy, both in front and in rear, with almost any amount of force, consisting of regulars, volunteers, and militia, that can be named. Retreat, for such a foe, would be out of the question, and re-embarkation an impossibility.

Therefore, so far as the system of 1816 was intended to defend the country from invasion along the Atlantic seaboard, steam, railroads, and the telegraph have rendered it as effete as did the invention of fire-arms the defences which the military science of that age had erected against the shafts of the archer.

It is not going too far to say that, as for invasion, we might raze every fortification along the Atlantic coast without exposing the country to the danger of being overrun by an enemy in war. He might, in such a case, take possession of our seaports, destroy our dock yards and arsenals, and do an incalculable amount of mischief, but as for his venturing to leave the strongholds on the seabord, and attempting to penetrate, even for a few miles into the interior, would be out of the question.

He would be besieged from the moment of his landing; he might return to us our cities in ruins, our dock yards in ashes; but as for invading the country, and marching his armies over it from place to place, our steam machines forbid it. Hence I maintain, we now want fortifications only to do what railroads and steam never can, viz: as before said, to protect our seaport towns from the great guns of big ships.

Suppose the system of 1816 to have been completed; that the fortifications therein contemplated had all been built, provisioned, equipped, and garrisoned. Now, saving only those which protect the large cities from the guns of men-ofwar, suppose the alternative should be presented to our military men, whether they would undertake to defend the country from invasion, with such a complete system of fortifications, but without the assistance of railroads, steamers, and telegraph, or with the assistance of railroads, steamers, and telegraph, but without the aid of the fortifications.

I suppose, could such an alternative be submitted to every officer of the

army,

from the oldest down to the youngest, that there would be but one answer, and that would be, "down with the forts, and give us the railroad, the locomotive, the steamboat, and the telegraph."

I do not mean to advance the opinion that railroads, steam, and the telegraph, with the military powers of concentration which they give us, have rendered fortifications entirely useless. By no means: steam and electromagnetism on the land can do but little against the tremendous power of armed ships on the water; and if these can bring any one of our large cities within the reach of their guns, its destruction is inevitable, despite all that the powers of the locoour motive and the telegraph can do. It is chiefly to keep such ships from burning cities and havens, within reach of their broadsides, that we want forts and castles. Therefore seeing that, in 1816, when the present system of defending the coast was planned, railroads and the magnetic telegraph were unknown, they now ought to involve modifications of that system. In military operations they are powerful auxiliaries. They introduce new elements and new features into the arts of war; they bear upon the whole system of attack and defence. They, therefore, cannot fail to make necessary certain modifications in any system of coast defence which was planned without regard to them.

With this exposition of my views, I proceed to answer your first question, viz: "1. To what extent, if any, ought the present system of fortifications for the protection of our seaboard to be modified, in consequence of the application of steam to vessels-of-war, the invention or improvement of projectiles, or other changes that have taken place since it was adopted in the year 1816 ?"

Let us first consider the modification applicable to the Atlantic seaboard, and then those that are applicable to the Pacific.

The only fortifications that are wanted along our Atlantic seaboard, except those at Key West and the Tortugas, at Ship island, and at one or two more such places, are those which will protect our cities and towns from the broadsides of men-of-war.

The forts already completed, or well advanced towards completion, are believed to be sufficient for this. They should, however, be mounted with heavier ordnance, and pieces of the most effective calibre for throwing explosive shot and shells. In 1840, the House of Representatives, by resolution of April 9th, called upon the War Department for a report-among other things, "of a full and connected system of national defence.'

The subject was referred to a board of engineer officers, who presented their views in a masterly manner. I have before referred to this well-drawn paper, and shall have frequent occasion to refer to it again. That report sustains the system of 1816. The source whence it comes entitles it to far more weight than is attached to any of my opinions. Nevertheless, honestly differing with that board in some of its positions, I hope I may be permitted to express that difference of opinion without laying myself liable to the charge, from any quarter, of want of respect for the distinguished officers who composed that board.

That report, which is by far the most able paper that I have seen in favor of the system of 1816, does not contemplate any guns for our fortifications heavier than a forty-two pounder, or an eight-inch howitzer; of course I speak technically, and do not allude to mortars.

It may be considered as a fact pretty well established, that two or three explosive nine or ten-inch shells, well aimed and properly planted, are enough to tear out the side of the largest ship, and completely to disable, if not wholly to destroy her.

I quote from the experiments made with nine-inch explosive shot, in the harbor of Brest, upon the Pacificateur, an eighty-gun ship.*

Vide an account of experiments made in the French navy for the trial of shell guns, &c., by J. H. Paixhan s Lieutenant Colonel-translated from the French by Lieutenant John A. Dahlgren, U. S. N.

The piece to be fired was mounted on a small pontoon, and planted off upon the water to the distance of about six hundred and forty yards from the eightygun ship, which was to be the target.

The experiments were made in the presence of a number of the most eminent officers in the French navy.

The first shot sufficed to determine opinions; but, to complete the evidence, twelve shots were fired.

The following is a summary from the official report on the occasion:

"The first shot struck low, and, as soon as the explosion was heard the commission repaired on board. A thick smoke filled the between decks, where the bomb had burst. The fire engine was worked and the smoke lasted ten or twelve minutes; the bomb had made a breach of eight and a half inches in diameter in the ship's side, which there was twenty-nine inches thick; it had torn off two feet of the inner plank and then exploded; made a hole in the orlop deck of two to three feet square, kncoked away and shattered to atoms more than one hundred and sixty square feet of timber.

“The second gun traversed the quarter-deck, carrying with it two peices of plank, one of which was five and a quarter feet long, then striking the mainmast obliquely, it knocked off a splinter from three to four feet long and nine and a half inches thick, and bursting, tore away a mast band ten and a half feet in circumference, weighing one hundred and thirty pounds; this mass of iron was driven with such a force that one of its halves struck the opposite bulwark, seventeen feet distant, where it flattened and adhered. The splinters of the bomb shattered the bitts, cut some of the braces, and would have injured many men and articles of rigging if the ship had been equipped. The explosion also set fire to a coil of rope.

"The third bomb entered the side, between two ports, struck and tore off an oaken knee seven feet five inches long and six and a half to thirteen and threequarter inches thick, which, with its iron fastenings, weighed more than two hundred and six pounds; then bursting, its splinters knocked down forty of the wooden figures nailed around the guns to represent men. The explosion also shattered one of the beams supporting the deck above, starting several planks, one of which was ten and a half feet long, and another five and a quarter feet," &c.

"To abridge this detail, I will," says the reporter, "only refer to the two most remarkable shots of the remaining nine.

"Perceiving that the bombs always passed through the side of the vessel, the charge of the gun was diminished each time. With four and a half pounds of powder, and always at six hundred and forty yards, a bomb struck in the wood, between two ports, and burst, tearing away the frame and planking, and making a breach of several feet in height and width, so shattered that all present thought that the shot would have endangered the vessel had it taken effect near the water-line.

"Besides this, two pieces of the iron work, weighing sixteen pounds, were driven in board by the force of the explosion, and nineteen figures knocked down.

"Finally, the twelfth and last bomb, with the same small charge and at the same distance, struck the corner of a port, knocked away a heavy piece of iron work, and lodged on the other side of the ship against an iron knee five and a quarter inches in size and firmly supported; the blow made three fissures in the iron, two of which were four and a quarter inches thick; and the bbmo still unbroken buried itself further in the side, burst, and knocked down twenty figures."

As to the havoc made upon a ship by these projectiles, the French commis

sion was of opinion that it was "so terrible and so great that it is thought that one or two bombs of this kind bursting in a battery would make such confusion as to cause the surrender of the vessel, or at least conduce materially to it ;" and "to produce, by the power of the bomb and its splinters, such damage in the frame that if the explosion should take place near the water-line the vessel would probably sink. There is no doubt on this subject," it was added, "as may evidently be perceived from the result of bomb No.-, which, had it struck a few feet lower, would certainly have done irreparable mischief,”

That any ship "must unavoidably give over the attack on being struck with a few shells."

"That it would be very useful to mount these guns either on floating pontoons, gunboats with sweeps, or steamers; and it is thought that for the defence of roads and coasts, or for attacking ships in a calm, or on a lee shore, the success of the bomb cannon would be infallible."

Furthermore, that commission of distinguished men also expressed the unanimous opinion "that these shell guns would be of incalculable utility in coast batteries, gunboats, or launches, bombardment, floating batteries, steamers," &c. The subject was brought before the Academy of Science, and the opinion of the board were indorsed by that body after full deliberation.

Subsequently a second trial was made upon the same ship in the presence of another board of officers, with like results. This board, after a full discussion as to the effect of these shells, gave it as their opinion likewise, that "their power is so terrible that should one or two bombs of this kind burst in a battery, the vessel would be rendered untenable; that the explosion of a bomb in the frame of a ship would be productive of great mischief; and if this occur at the water-line, the vessel must founder, as may be inferred from the effect of bomb No. 8."

Respecting the use of this kind of ordnance in fortifications the commission were unanimously of the opinion that these guns are capable of prodigious effect in coast batteries, as no ship of any force could possibly withstand such a fire at 610 guns or 1,300 yards; that it will also be desirable to mount the new artillery on floating batteries, launches, gunboats, or steamers; and it is believed that the bomb cannon is well adapted to the defence of roads and coasts, the attack of ships in a calm, or on a lee shore," &c.

Moreover, the experiments which have been conducted by the Bureau of Ordnance and Hydrography of the United States navy, show that guns of this heavy calibre will carry further and truer, and penetrate deeper than 32-pounders; and, therefore, considering that the navies of the world are substituting these heavy guns, whenever they can, for the old 32-pounders, and considering that it is ships, and not sieges, that our fortifications are to be called upon to withstand, it appears to me it would be both prudent and judicious so to modify the plan of 1816 as to furnish our forts, as far as practicable, with heavy ordnance, all of the most effective and destructive kind.

Whether a ship's battery, throwing 10-inch solid shot, would not readily breach the walls of our strongest forts is worthy of inquiry. The concussion from such a broadside would be tremendous. It is true there are no ships at present that can throw such a broadside, yet it is thought practicable and desirable by navy officers to build such ships, and experiments have been made which leave no doubt that such ships will be built. Whether our ramparts on shore could withstand such ordnance is not for me to say. I therefore suggest the inquiry.

It is a curious fact that, as a general rule, the fire of large forts has always been proportionally less destructive than those mounting only a few guns, and having those in barbette, in open battery, either with or without breastworks.

This may be accounted for by the smoke; for wild firing applies not only to