Creating the Monitor


The efforts by the Confederates to construct an ironclad in Hampton Roads were well known to the Federal authorities. Throughout the summer of 1861, newspaper reporters as well as the general public visited the Gosport Yard to observe the work on the Virginia. Newspapers throughout the South carried regular updates on the progress of the conversion. Similar stories were also reported in Northern papers. As the work proceeded, it became evident to the North that if the Confederacy succeeded in launching an armored vessel, there was not a Union ship that could challenge her.

It was the need to offset this potential Confederate naval superiority that moved the United States Navy Department to appoint an Ironclad Board of naval officers to seek and evaluate plans for the construction of ironclad vessels for Federal service. On August 3, 1861, Union Secretary of the Navy Gideon Welles published an announcement calling on designers to submit plans for ironclad warships to the Navy Department. This was not the first time that the United States had toyed with the idea of building ironclad vessels. Since the late 1840s, the navy had considered plans for designing and testing ironclads. In 1842, Robert L. Stevens won a contract to construct a floating iron battery for the navy. However, the Stevens battery was never completed.

The first successful launching of ironclad vessels for United States service occurred during the summer of 1861, not under the direction of the navy, but rather the U.S. Army Quartermaster Corps. The War Department ordered the building of ironclad gunboats on the Mississippi under the direction of Samuel Pook and James Eads. These ironclad river steamers known as “Pook Turtles” or “Eads’ Gunboats” would be used throughout the war on the western rivers. Still, the command of the Union Navy remained conservative and cautious in approaching iron shipbuilding.

Following Welles’s call for plans, a number of designers presented proposals to the Ironclad Board for consideration. Among the designers who submitted proposals was Cornelius Bushnell. Bushnell controlled several railroads in Connecticut, and now ventured to enter the world of naval architecture. With the help of naval constructor Samuel Pook, Bushnell developed a plan for an ironclad steamer. Bushnell’s ship, to be called the Galena, was a conventional ship with armor constructed of iron bars laying over iron rails. To verify the seaworthiness of his ship, Bushnell sought out the advice of the renowned engineer John Ericsson. According to Bushnell, after Ericsson had confirmed that the Galena’s design was sound, Ericsson produced a model of an “impregnable iron battery” that he had proposed to French Emperor Napoleon III in 1854. The model showed a ship with an almost submerged hull and a single revolving turret fixed to the deck containing a single cannon. Though Napoleon had not accepted the plan, Ericsson emphasized to Bushnell that the battery’s design was viable and that the ship could be built very quickly.

Bushnell was so impressed with Ericsson’s model that he took it to Secretary Welles, who agreed that the design had “extraordinary and valuable features” and that it should be submitted to the Ironclad Board for consideration. Bushnell presented Ericsson’s model to the Board, but it was rejected as too outlandish for consideration. Bushnell then persuaded Ericsson himself to appear before the Board to defend the design.

Ericsson’s defense of his design was obviously successful. When the Ironclad Board submitted its final report to Secretary Welles, Ericsson’s was one of three designs recommended for approval. The contract offered to Ericsson was in the amount of $275,000, but it stipulated that the ship must be completed in one hundred days, and that it must prove successful in every way or payment would be withheld.


John Ericsson

John Ericsson was born in the province of Vermland, Sweden, on July 31, 1803. The son of a mining engineer, Ericsson showed an early interest in mechanics. By the age of ten, he had designed and constructed a miniature sawmill. At the age of 13, as a cadet in the Swedish navy, he was appointed supervisor of more than 600 men on a major ship canal project. At the age of 17 he entered the Swedish army, joining as an ensign in the 23rd. The 23rd Corps served in part as a specialized engineering unit for the army, and while assigned there, Ericsson had extensive opportunities to sharpen his mechanical and engineering skills. The army also introduced him to the use and design of artillery. While serving in the army, Ericsson became interested in steam engines and developed the theory for his caloric engine, which operated on the principle that air heated to very high temperature could be used to drive engines.

In 1826 Ericsson published a paper on his work to develop a caloric engine. That year he traveled to England to demonstrate his invention to the British Society of Civil Engineers. Sadly, the engine failed in the demonstration, and Ericsson, now penniless and with a tarnished reputation as an engineer, was stranded in England. Fortunately for Ericsson, present at the demonstration was an English engineer named John Braithwaite. Though Braithwaite had witnessed the failure of Ericsson’s engine, he was impressed with the young Swede’s determination and offered him a position as a partner in his firm. The partnership was to prove particularly fruitful. In the ten years that Braithwaite and Ericsson worked together they developed some 30 new inventions, including an evaporator, a depth finder, a series of improved engines, and a steam engine with a surface condenser.

Taking part in a contest to develop a train locomotive for the Liverpool and Manchester Railway, in 1829 Ericsson developed an improved steam locomotive. Named the Novelty, Ericsson’s steam locomotive weighed only two tons. During trials the Novelty covered a mile in 53 seconds, and exceeded 20 miles per hour while pulling three time its own weight. Despite the Novelty’s success, the railroad granted the contract to a competing firm.

Ericsson Propeller In 1826 Ericsson published a paper on his work to develop a caloric engine. That year he traveled to England to demonstrate his invention to the British Society of Civil Engineers. Sadly, the engine failed in the demonstration, and Ericsson, now penniless and with a tarnished reputation as an engineer, was stranded in England. Fortunately for Ericsson, present at the demonstration was an English engineer named John Braithwaite. Though Braithwaite had witnessed the failure of Ericsson’s engine, he was impressed with the young Swede’s determination and offered him a position as a partner in his firm. The partnership was to prove particularly fruitful. In the ten years that Braithwaite and Ericsson worked together they developed some 30 new inventions, including an evaporator, a depth finder, a series of improved engines, and a steam engine with a surface condenser.

Taking part in a contest to develop a train locomotive for the Liverpool and Manchester Railway, in 1829 Ericsson developed an improved steam locomotive. Named the Novelty, Ericsson’s steam locomotive weighed only two tons. During trials the Novelty covered a mile in 53 seconds, and exceeded 20 miles per hour while pulling three time its own weight. Despite the Novelty’s success, the railroad granted the contract to a competing firm.

Though the British navy rejected the idea of using screw propellers on warships, an American naval officer, Robert Stockton, was impressed with what he had seen Ericsson produce. Stockton persuaded Ericsson to immigrate to the United States. In 1839, with Stockton’s influence, Ericsson was awarded a contract to build a screw-propelled warship for the United States Navy. Launched in 1843, the USS Princeton was the first warship in naval history to be designed and built as a screw-powered ship.

Though the Princeton proved to be a successful design, she placed a black mark on Ericsson’s reputation. In 1844, while steaming on a demonstration cruise with a party of guests including President John Tyler, the secretaries of state and the navy, and two senators, one of the Princeton’s guns exploded, killing five people (including both secretaries) and wounding 17 others. Although the gun that exploded was not of Ericsson’s design, he was blamed for the disaster. A congressional investigation eventually cleared Ericsson of any responsibility for the accident aboard the Princeton, but the damage to his reputation had been done. Ericsson developed an animosity for the United States Navy that was to last for nearly 20 years.

After the explosion on the Princeton, Ericsson continued his work as an engineer and designer. In 1854, during the time when the French navy was experimenting with ironclad ships, Ericsson submitted to Napoleon III a design for a floating battery. Ericsson’s design called for a battery that was steam powered and completely armored with iron plate. The profile of the battery was radically new. The entire engine space and living areas of the crew were below the water line. Only a flat armored gun platform supporting a revolving gun turret could be seen above the water. “Ericsson’s Impregnable Battery and Revolving Cupola” was revolutionary in its design and construction. In fact, it was perhaps too radical, for Napoleon III did not contract for the construction of any of Ericsson’s batteries.

Navy Department – Bureau of Yards and Docks
September 16, 1861


The undersigned, constituting a board appointed by your order of the 8th ultimo, proceeded to the duty assigned to them, in accordance with the first section of an act of Congress, approved 3d of August 1861, directing the Secretary of the Navy “to appoint a board of three skillful naval officers to investigate the plans and specifications that may be submitted for the construction or completing of iron-clad steamships or steam batteries to be built; and there is hereby appropriated, out of any money in the treasury not otherwise appropriated, the sum of one million five hundred thousand dollars.”

Distrustful of our ability to discharge this duty, which the law requires should be performed by three skillful naval officers, we approach the subject with diffidence, having no experience and but scanty knowledge in this branch of naval architecture.

Application was made to the department for a naval constructor, to be placed under our orders, with whom we might consult; but it appears that they are all so employed on The construction of iron-clad steamships of war is now zealously claiming the attention of foreign naval powers. France led off; England followed, and is now somewhat extensively engaged in the system; and other powers seem to emulate their example, though on a smaller scale.

Opinions differ amongst naval and scientific men as to the policy of adopting iron armature for ships-of-war. For coast and harbor defense they are undoubtedly formidable adjuncts to fortifications on land. As cruising vessels, however, we are sceptical as to their advantages and ultimate adoption. But whilst other nations are endeavoring to perfect them, we must not remain idle.

The enormous load of iron, as so much additional weight to the vessel; the great breadth of beam necessary to give her stability; the short supply of coal she will be able to stow in bunkers; the greater power required to propel her and the largely increased cost of construction, are objections to this class of vessels as cruisers which we believe it is difficult successfully to overcome. For river and harbor service we consider iron-clad vessels of light draught, or floating batteries thus shielded as very important; and we feel at this moment the necessity of them on some or our rivers and inlets to enforce obedience to the laws. We, however, do not hesitate to express the opinion, notwithstanding all we have heard or seen written on the subject, that no ship or floating battery, however heavily she may be plated, can cope successfully with a properly constructed fortification of masonry. The one is fixed and immovable, and though constructed of a material which may be battered by shot, can be covered, if need be, by the same or much heavier armor than a floating vessel can bear, whilst the other is subject to disturbances by winds and waves, and to the powerful effects of tides and currents.

Armored ships or batteries may be employed advantageously to pass fortifications on land for ulterior objects of attack, or run a blockade, or to reduce temporary batteries on the shores of rivers and the approaches to our harbors.

From what we know of the comparative advantages and disadvantages of ships constructed of wood over those of iron, we are clearly of opinion that no iron-clad vessel of equal displacement can be made to obtain the same speed as one not thus encumbered, because her form would be better adapted to speed. Her form and dimensions, the unyielding nature of the shield, detract materially in a heavy sea from the life, buoyancy, and spring which a ship built of wood possesses.

Wooden ships may be said to be but coffins for their crews when brought in conflict with iron-clad vessels; but the speed of the former, we take for granted, being greater than that of the latter, they can readily choose their position, and keep out of harm’s way entirely.

Recent improvements in the form and preparation of projectiles, and their increased capacity for destruction, have elicited a large amount of ingenuity and skill to devise means for resisting them in their construction of ships-of-war. As yet we know of nothing superior to the large and heavy spherical shot in its destructive effects on vessels, whether plated or not.

Rifled guns have greater range, but the conical shot does not produce the crushing effect of spherical shot.

It is assumed that 4 inch plates are the heaviest armor a sea going vessel can safely carry. These plates should be of tough iron, and rolled in large long pieces. This thickness of armor, it is believed, will resist all projectiles now in general use at a distance of 500 yards, especially if the ship’s sides are angular.

Plates hammered in large masses are less fibrous and tough than when rolled. The question whether wooden backing, or any elastic substance behind the iron plating will tend to relieve at all the frame of the ships from the crushing effect of a heavy projectile, is not yet decided. Major Barnard says “to put an elastic material behind iron is to insure its destruction.” With all difference to such elastic substance (soft wood, perhaps, is best) might relieve the frame of the ship somewhat from the terrible shock of a heavy projectile, though the plate should be fractured.

With respect to a comparison between ships of iron and those of wood, without plating, high authorities in England differ as to which is best. The tops of ships built of iron, we are told, wear out three bottoms; whilst the bottoms of those built of wood will outwear three tops. In deciding upon the relative merits of iron and wooden-framed vessels, for each of which we have offers, the board is of opinion that it would be well to try a specimen of each as both have distinguished advocates. One strong objection to iron vessels which, so far as we know, has not yet been overcome, is the oxidation or rust in salt water, and their liability of becoming foul under water by the attachment of sea grass and animalcules to their bottoms. The best preventative we know of is a coating of pure zinc paint, which, so long as it lasts, is believed to be an antidote to this cause of evil.

After these brief remarks on the subject generally, we proceed to notice the plans and offers referred to us for construction of plated vessels and floating batteries.

It has long been suggested that the most ready mode of obtaining an iron-clad ship-of-war would be to contract with responsible parties in England for its complete construction; and we are assured that parties there are ready to engage in such an enterprise on terms more reasonable, perhaps, than such a vessels could be built in this country, having greater experience and facilities than we possess. Indeed, we are informed there are no mills and machinery in this country capable of rolling iron 4 inches thick, though plates might be hammered to that thickness in many of our workshops. As before observed, rolled iron is considered much the best, and the difficulty of rolling it increases rapidly with the increase of thickness. It has, however, occurred to us that a difficulty might arise with the British government, in case we should undertake to construct ships-of-war in that country, which might complicate their delivery; and moreover, we are of opinion that every people or nation who can maintain a navy should be capable of constructing it themselves.

Our immediate demands seem to require, first, so far as practicable, vessels invulnerable to shot, of light draught of water, to penetrate our shoal harbors, rivers and bayous. We, therefore, favor the construction of this class of vessels before going into a more perfect system of large iron-clad sea-going vessels of war. We are here met with the difficulty of encumbering small vessels with armor, which, from their size, they are unable to bear. We, nevertheless, recommend that contracts be made with responsible parties for the construction of one or more iron-clad vessels or batteries of as light a draught of water as practicable consistent with their weight of armor. Meanwhile, availing of the experience thus obtained, and the improvements which we believe are yet to be made by other naval powers in building iron-clad ships, we would advise the construction, in our own dock-yards, of one or more of these vessels upon a large and more perfect scale, when Congress shall see fit to authorize it. The amount now appropriated is not sufficient to build both classes of vessels to any great extent.

We have made a synopsis of the propositions and specifications submitted, which we annex, and now proceed to state, in brief, the results of our decisions upon the offers presented to us.

J. Ericsson, New York, page 19 – This plan of a floating battery is novel, but seems to be based upon a plan which will render the battery shot and shell proof. We are somewhat apprehensive that her properties for sea are not such as a sea-going vessel should possess. But she may be moved from one place to another on the coast in smooth weather. We recommend that an experiment be made with one battery of this description on the terms proposed, with a guarantee and forfeiture in case of failure in any of the properties and points of the vessel as proposed.

Price, $275,000; length of vessel, 172 feet; breadth of beam, 41 feet; depth of hold, 11 feet; time, 100 days; draught of water, 10 feet; displacement 1,255 tons; speed per hour, nine statute miles.

John W. Nystrom, Philadelphia, 1216 Chestnut Street, page 1 – The plan of (quadruple) guns is not known, and cannot be considered. The dimensions would not float the vessel without guards, which we are not satisfied would repel shot. We do not recommend this plan.

Price, about $175,000; length of vessel, 175 feet; breadth of beam, 27 feet; depth of hold, 13 feet; time, four months; draught of water, 10 feet; displacement, 875 tons; speed per hour, 12 knots.

William Perine, New York, 2777 post office box, presents three plans. The specifications and drawings are not full. The last proposal (No. 3, page 2) for the heavy plating is the only one we have considered; but there is neither drawing nor model, and the capacity of the vessel, we think, will not bear the armor and armament proposed.

Price, $621,000; length of vessel, 225 feet; breadth of beam, 45 feet; depth of hold, 15 feet; time, 9 months, draught of water, 13 feet; displacement, 2,454 tons; speed per hour, 10 knots.

John C. Ferre, Boston, page 9 – Description deficient. Not recommended. Sent a model, but neither price, time, nor dimensions stated.

E. S. Renwick, New York, 335 Broadway, presents drawings, specification, and model of an iron-clad vessel of large capacity and powerful engines, with great speed, capable of carrying a heavy battery, and stated to be shotproof and a good sea-boat. The form and manner of construction and proportions of this vessel are novel, and will attract the attention of scientific and practical men. She is of very light draught of water, and on the question whether she will prove to be a safe and convertible sea-boat we do not express a decided opinion. Vessels of somewhat similar form, in that part of vessel which is immersed, of light draught of water on our western lakes, have, we believe, proved entirely satisfactory in all weathers. To contract the effect of waves, when disturbed by the winds, by producing a jerk, or sudden rolling motion of flat, shoal vessels, it is proposed to carry a sufficient weight above the center of gravity to counterpoise the heavy weight below, which is done in this ship by the immense iron armor. If, after a full discussion and examination by experts on this plan, it should be decided that she is a safe vessel for sea service, we would recommend the construction upon it of one ship at one of our dock yards.

The estimate cost of this ship, $1,500,000, precludes action upon the plan until further appropriations shall be made by Congress for such objects.

Time not stated; length of vessel, 400 feet; breadth of beam 60 feet; depth of hold, 33 feet; draught of water, 16 feet; displacement, 6,520 tons; speed per hour, at least 18 miles.

Whitney & Rowland, Brooklyn, Greenpoint, page 13, propose an iron gunboat, armor of bars of iron and thin plate over it. No price stated. Dimensions of vessel, we think, will not bear the weight and possess stability. Time, 5 months. Not recommended.
Length of vessel, 140 feet; breadth of beam, 28 feet; depth of hold, 13 feet; draught of water, 8 feet.

Donald McKay, Boston, page 16 – Vessel, in general dimensions and armor, approved. The speed estimated slow. The cost precludes the consideration of construction by the board.

Price, k$1,000,000; length of vessel, 227 feet; breadth of beam, 50 feet; depth of hold, 26 feet; time, 9 to 10 months; draught of water, 13 feet; displacement, 1,215 tons; speed, not stated.

William H. Wood, Jersey City, N.J., page 14 – Dimensions will not float the guns high enough; not recommended.

Price, $225,000; length of vessel, 160 feet; breadth, 34 feet; depth of hold, 22 feet; time, 4 months; draught of water, 13 feet; displacement, 1,215 tons; speed, not stated.

Merrick and Sons, Philadelphia, pages 7 and 8. – Vessel of wood and iron combined. This proposition we consider the most practicable one for heavy armor. We recommend that a contract be made with that party, under the guarantee, with forfeiture in case of failure to comply with specifications; and that the contract require the plates to be 15 feet long and 36 inches wide, with a reservation of some modifications, which may occur as the work progresses, not to affect the cost.

Price, $225,000; length of vessel, 220 feet; breadth of beam, 60 feet; depth of hold 23 feet; time, 9 months; draught of water, 13 feet; displacement, 3,296 tons; speed per hour, 9 knots.

Benjamin Rathburn,_____________, page 20. We do not recommend the plan for adoption.

Price not stated; length of vessel not stated; breadth of beam, 80 feet; depth of hold, 74 feet; time not stated; draught of water, 25 feet; displacement, 15,000 tons; speed not stated. Specifications incomplete.

Henry R. Dunham, New York, page 11. – Vessel too costly for the appropriation; no drawings or specifications; not recommended.

Price, $1,200,000; length of vessel, 325 feet; breadth of beam 60 feet; depth of hold not stated; time, 15 to 18 months; draught of water, 16 feet; displacement not stated; speed per hour, 12 miles. 

C.S. Bushnell, & Co., New Haven, Conn., page 121, propose a vessel to be iron-clad, on the rail and plate principal, and to obtain high speed. The objection to this vessel is the fear that she will not float her armor and load sufficiently high, and have stability enough for a sea vessel. With a guarantee that she shall do these, we recommend on that basis a contract.

Price, $235,250; length of vessel, 180 feet; breadth of beam,_____feet; depth of hold, 12 2/3 feet; time, 4 months; draught of water, 10 feet; displacement,________tons; speed per hour, 12 knots.

John Westwood, Cincinnati, Ohio, page 17. – Vessel of wood, with iron armor; plan good enough, but the breath not enough to bear armor. No detailed specification; no price or time stated; only a general drawing. Not recommended.

Neafie & Levy, Philadelphia, page 5. – No plans or drawings, therefore not considered. Neither price nor time stated. Length of vessel, 200 feet; breadth of beam, 40 feet; depth of hold, 15 feet; draught of water, 13 feet; displacement, 1,748 tons; speed per hour, 10 knots. 
Wm. Norris, New York, 26 Cedar Street, page 6. – Iron boat without armor. Too small, and not received.

Price, $32,000; length of vessel, 83 feet; breadth of beam, 25 feet; depth of hold, 14 feet; time, 60 to 75 days; draught of water, 3 feet; displacement, 90 tons; speed not stated.

Wm. Kingsley, Washington, D.C., page 10. – proposes a rubber-clad vessel, which we cannot recommend. No price or dimension stated.

A. Beebe, New York, 82 Broadway, page 18. – Specification and sketch defective. Plan not approved.

Price, $50,000; length of vessel, 120 feet; breadth of beam, 55 feet; depth not stated; time, 100 days; draught of water, 6 feet; displacement, 1,000 tons; speed per hour, 8 knots.

These three propositions recommended, viz: Bushnell & Co., New Haven, Connecticut; Merrick & Sons, Philadelphia; and J. Ericsson, New York, will absorb $1,290,250 of the appropriation of $1,500,00, leaving $209,750 yet unexpended.

The board recommends that armor with heavy guns be placed on one of our river craft, or, if none will bear it, to construct a scow, which will answer to plate and shield the guns, for the river service on the Potomac, to be constructed or prepared by the government at the navy yard here for immediate use.

We would further recommend that the department ask of Congress, at its next session, an appropriation, for experimenting on iron plates of different kinds, of $10,000.

All of which is respectfully submitted. 
Hon. Gideon Welles,
Secretary of the Navy Ironsides

John Ericsson’s design for the USS Monitor

To meet the deadline set by the government, Ericsson subcontracted the construction and fabrication of his ironclad to eight foundries In a particularly ambitious plan, each subcontractor supplied various components of the ship at separate locations, then shipped the parts to a central location for assembly. Delamater Iron Works of New York City constructed the engines and boilers. Novelty Iron Works of New York City rolled the iron plates for the turret and oversaw its assembly, and Clute Brothers and Company of Schenectady produced the donkey engine to power the turret. Meanwhile, Holdane and Company of New York City, Albany Iron Works of Troy, and H. Abbot and Son of Baltimore rolled additional iron plate for the turret, as well as bars and rivets. Two iron port stoppers were furnished by the Niagara Steam Forge of Buffalo. As these parts were produced, they were shipped to Continental Iron Works in Greenpoint, New York, where the hull was laid and the final assembly was performed.

The most innovative feature of the Monitor and the one that became her distinguishing characteristic was her revolving turret. Though other designers had toyed with the idea of developing turrets for warships, Ericsson’s Monitor was the first warship to use the invention successfully. The turret rested amidships of the vessel and was furnished with a separate steam engine that propelled the turret in a complete rotation. It measured 20 feet in diameter and 9 feet in height, and its armored walls were made of eight layers of 1-inch armor plate. Two massive XI-inch Dahlgren smooth-bore guns, capable of firing solid shot weighing 180 pounds, were installed inside the turret. Though the Monitor would go into battle with only two guns, she had a distinct advantage even over an opponent with ten cannon. This was because the revolving turret would allow her to fire and aim her guns rapidly in any direction regardless of the direction in which the ironclad might be steaming. All other ships of her time were forced to aim their guns in part by steering the vessel into a position where the guns, mounted in broadside arrangement, could be brought to bear on the enemy.

A further innovation of Ericsson’s design was the Monitor’s extremely low profile: only 18 inches of the deck was visible above the water line. Essentially the only target an enemy had when firing on the Monitor was her heavily armored turret and the low iron pilot house on the forward section of the deck. Enemy gunners would be hard pressed in the heat of battle to score many hits on such a meager target. The assembly of Ericsson’s battery was in itself an amazing engineering feat. Eight foundries, working independently and perhaps with no clear idea of what the final product would look like, successfully produced a ship of revolutionary design. 

Ericsson was not only a genius of engineering, but a genius of organization and efficiency. When the ship was launched on January 30, 1861, Ericsson had missed his one hundred-day deadline by 18 days, but no one seemed to notice. The navy had its Monitor to check the South’s Virginia.

MONITOR, October 4, 1861

This Contract in two parts, made and entered into this Fourth day of October, Anno Domini One Thousand Eight hundred and Sixty-one, between J. Ericsson of the City of New York as principal, and John F. Winslow, John A. Griswold and C.S. Bushnell as sureties on the first part, and Gideon Welles, Secretary of the Navy for and in behalf of the United States on the second part, WITNESSETH:

That in consideration of the payments hereinafter provided for, the party of the first pat hereby contracts and agrees to construct an Iron Clad Shot-Proof Steam Battery of iron and wood combined on Ericsson’s plan; the lower vessel to be wholly of iron and the upper vessel of wood; the length to be one hundred and seventy-nine (179) feet, extreme breadth forty-one (41) feet, and depth five (5) feet or larger if the party of the first part shall think it necessary to carry the armament and stores required, the vessel to be constructed of the best materials and workmanship throughout, according to the plan and specifications hereunto annexed forming a part of this contract; and in addition to said specifications the party of the first part hereby agree to furnish Masts, Spars, Sails and Rigging of sufficient dimensions to drive the vessel at the rate of six knots per hour in a fair breeze of wind; and the party of the first part will also furnish in addition to the said specifications a Condenser for making fresh water for the boilers on the most approved plan.

And the party of the first part further contracts and engages that the said vessel shall have proper accommodations for her stores of all kinds including provisions for one hundred persons for ninety days, and shall carry 2500 gallons of water in tanks; that the vessel shall have a speed of eight sea miles or knots per hour under steam for twelve consecutive hours, and carry fuel for her engines for eight days consumption at that speed; the deck of the vessel when loaded to be eighteen inches above load line amidships; that she shall possess sufficient stability with her armament, stores and crew on board for safe sea-service in traversing the coast of the United States; that her crew shall be properly accommodated and that the apparatus for working the Battery shall prove successful and safe for the purpose intended, and that the vessel machinery and appointments in all their parts hall work to the entire satisfaction of the party of the second part.

And the party of the second part hereby agrees to pay for the vessel complete as aforesaid after trial and satisfactory test, the sum of Two hundred and seventy-five thousand dollars in coin or Treasury notes at the option of the party of the second part in the following manner, to wit: When the work shall have progressed to the amount of Fifty thousand dollars in the estimation of the Superintendent of the vessel on the part of the United States, that sum shall be paid to the party of the first part on certificate of said Superintendent, and thereafter similar payments according to the certificates of said Superintendent, deducting, reserving and retaining from each and every payment Twenty-five per centum, which reservation shall be retained until after the completion and satisfactory trial of the vessel, not to exceed ninety days after she shall be ready for sea.

And it is further agreed between the said parties that the said vessel shall be complete in all her parts and appointments for service, and any omission in these specifications shall be supplied to make her thus complete; and in case the said vessel shall fail in performance of speed for sea service as before stated, or in the security or successful working of the turret and guns with safety to the vessel and the men in the turret, or in her buoyancy to float and carry her battery as aforesaid, then and in that case the party of the first part hereby bind themselves, their heirs, executors, administrators and assigns by these presents to refund to the United States the amount of money advanced to them on said vessel within thirty days after such failure shall have been declared by the party of the second part, and the party of the first part acknowledge themselves indebted to the United States in liquidated damages to the full amount of money advanced as aforesaid. And it is further agreed that the vessel shall be held by the United States as collateral security until said amount of money advanced as aforesaid shall be refunded.

And the party of the first part does further engage and contract that no member of Congress, officer of the Navy , or any person holding any office or appointment under the Navy Department shall be admitted to any share or part of this contract or agreement, or to any benefit to arise thereupon. And it is hereby expressly provided, and this contract is upon this express condition that if any such member of Congress, officer of the Navy, or other person above named shall be admitted to any share or part of this contract, or to any benefit to arise under it, or in case of the party of the first part shall in any respect fail to perform this contract on their part, the same may be, at the option of the United States, declared null and void, without affecting their right to recover for defaults which may have occurred.

It is further agreed between the said parties that said vessel and equipment in all respects shall be completed and ready for sea in on hundred days from the date of this Indenture,

Secretary of the Navy.

Signed, sealed and delivered

In the presence of
W.L. BARNES, to the signatures J. Ericsson, John F. Winslow, John A. Griswold, C.S. Bushnell.
JOS. SMITH as to signature of G. Welles.     

  • The work on the Merrimac [Virginia] had progressed so far that no structure of large dimensions could possibly be completed in time to meet her.

  • The well-matured plan of erecting a citadel of considerable dimensions on the ample deck of the razeed [sic] Merrimac admitted of a battery of heavy ordnance so formidable that no vessel of the ordinary type, of small dimensions, could withstand its fire.

  • The battery designed by the naval constructor of the Confederate States, in addition to the advantage of ample room and numerous guns, presented a formidable front to an opponent’s fire by being inclined to such a degree that shot would be readily deflected. Again, the inclined sides, composed of heavy timbers well braced, were covered with two thicknesses of bar iron, ingeniously combined, well calculated to resist the spherical shot peculiar to the Dahlgren and Rodman system of naval ordnance adopted by the United States Navy.

  • The shallow waters on the coast of the Southern States called for very light draught; hence the upper circumference of the propeller of the battery would be exposed to the enemy’s fire unless thoroughly protected against shot of heavy caliber. A difficulty was thus presented which apparently could not be met by any device which would not seriously impair the efficiency of the propeller.

  • The limited width of the navigable parts of the Southern rivers and inlets presented an obstacle rendering man¦uvring [sic] impossible; hence it would not be practicable at all times to turn the battery so as to present a broadside to the points to be attacked.

  • The accurate knowledge possessed by the adversary of the distance between the forts on the river banks within range of his guns, would enable him to point the latter with such accuracy that unless every part of the sides of the battery could be made absolutely shot-proof, destruction would be certain. It may be observed that the accurate knowledge of range was an advantage in favor of the Southern forts which placed the attacking steam-batteries at great disadvantage.

  • The difficulty of manipulating the anchor within range of powerful fixed batteries presented difficulties which called for better protection to the crew of the batteries than any previously known.

John Ericsson
Century, December 1885

The Launching of the USS Monitor

New York – January 20, 1862


In accordance with your request, I now submit for your approbation a name for the floating battery at Greenpoint. The impregnable and aggressive character of this structure will admonish the leaders of the Southern Rebellion that the batteries on the banks of their rivers will no longer present barriers to the entrance of the Union forces. The iron-clad intruder will thus prove a severe monitor to those leaders. But there are other leaders who will also be startled and admonished by the booming of the guns from the impregnable iron turret. “Downing Street” will hardly view with indifference this last “Yankee Notion,” this monitor. To the Lords of the admiralty the new craft will be a monitor, suggesting doubts as to the propriety of completing those four steel clad ships at three and a half million apiece. On these and many similar grounds, I propose to name the new battery “Monitor.”

Your obedient servant,
J. Ericsson 
Gustavus V. Fox
Assistant Secretary of the Navy
Washington, D.C.

The first real object of interest which presented itself was the Monitor lying off Fortress Monroe. It reminded me of what I once heard a man say to his neighbor about his wife; said he, “Neighbor, you might worship your wife without breaking either of the ten commandments.” “How is that↓” asked the man; “Because she is not the likeness of anything in heaven above, or in the earth beneath, or in the waters under the earth.” So thought I of the Monitor.

There she sat upon the water a glorious impregnable battery, the wonder of the age, the terror of rebels, and the pride of the North. The Monitor is so novel in structure that a minute description will be necessary to convey an accurate idea of her character.

She has two hulls. The lower one is of iron, five-eighths of an inch thick. The bottom is flat, and six feet six inches in depth – sharp at both ends, the cut-water retreating at an angle of about thirty degrees. The sides, instead of having the ordinary bulge, incline at an angle of about fifty-one degrees. This hull is one hundred and twenty-four feet long, and thirty-four feet broad at the top. Resting on this is the upper hull, flat-bottomed, and both longer and wider than the lower hull, so that it projects over in every direction, like the guards of a steamboat. It is one hundred and seventy-four feet long, forty-one feet four inches wide, and five feet deep. These sides constitute the armor of the vessel. In the first place is an inner guard of iron, half an inch thick. To this is fastened a wall of white oak, placed endways, [sic] and thirty inches thick, to which are bolted six plates of iron, each an inch thick, thus making a solid wall of thirty-six and a half inches of wood and iron. This hull is fastened upon the lower hull, so that the latter is entirely submerged, and the upper one sinks down three feet into the water. Thus but two feet of hull are exposed to a shot. The under hull is so guarded by the projecting upper hull, that a ball, to strike it, would have to pass through twenty-five feet of water. The upper hull is also pointed at both ends.

The deck comes flush with the top of the hull, and is made bomb-proof. No railing or bulwark rises above the deck. The projecting ends serve as a protection to the propeller, rudder and anchor, which cannot be struck. Neither the anchor or chain is ever exposed. The anchor is peculiar, being very short, but heavy. It is hoisted into a place fitted for it, outside of the lower hull, but within the impenetrable shield of the upper one. On the deck are but two structures rising above the surface, the pilot-house and turret. The pilot-house is forward, made of plates of iron, the whole about ten inches in thickness, and shot-proof. Small slits and holes are cut through, to enable the pilot to see his course. The turret, which is apparently the main feature of the battery, is a round cylinder, twenty feet in interior diameter, and nine feet high. It is built entirely of iron plates, one inch in thickness, eight of them securely bolted together, one over another. Within this is a lining of one-inch iron, acting as a damper to deaden the effects of a concussion when struck by a ball – thus there is a shield of nine inches of iron.

The turret rests on a bed-plate, or ring, of composition, which is fastened to the deck. To help support the weight, which is about a hundred tons, a vertical shaft, ten inches in diameter, is attached and fastened to the bulk-head. The top is made shot-proof by huge iron beams, and perforated to allow of ventilation. It has two circular port-holes, both on one side of the turret.

Three feet above the deck, and just large enough for the muzzle of the gun to be run out. The turret is made to revolve, being turned by a special engine. The operator within, by a rod connected with the engine, is enabled to turn it at pleasure. It can be made to revolve at the rate of sixty revolutions a minute, and can be regulated to stop within half a degree of a given point. When the guns are drawn in to lad, the port-hole is stopped by a huge iron pendulum, which falls to its place, and makes that part as secure as any, and can be quickly hoisted to one side. The armanent [sic] consists of two eleven-inch Dahlgren guns. Various improvements in the gun-carriage enable the gunner to secure almost perfect aim.

The engine is not of great power, as the vessel was designed as a battery, and not for swift sailing. It being almost entirely under water, the ventilation is secured by blowers, drawing the air in forward, and discharging it aft. A separate engine moves the blowers and fans the fires. There is no chimney, so the draft must by entirely artificial. The smoke passes out of gratings in the deck. Many suppose the Monitor to be merely an iron-clad vessel, with a turret; but there are, in fact, between thirty and forty patentable [sic] inventions upon her, and the turret is by no means the most important one. Very properly, what these inventions are is not proclaimed to the public.