[
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The building of the “monitor.”
The introduction of
General Paixhans's brilliant invention, the shell-gun, in 1824, followed, in 1858, by the successful application of armor-plating to the steam-frigate
La Gloire, under Napoleon III., compelled an immediate change in naval construction which startled the maritime countries of
Europe, especially
England, whose boasted security behind her “wooden walls” was shown to be a complete delusion.
The English naval architects, however, did not overlook the fact that their French rivals, while producing a gun which rendered wooden navies almost useless, had also by their armor-plating provided an efficient protection against the destructive
Paixhans shell.
Accordingly, the
Admiralty without loss of time laid the keel of the
Warrior, an armored iron steam-frigate 380 feet long, 58 feet beam, 26 feet draught, and 9200 tons displacement.
The work being pushed with extraordinary vigor, this iron-clad ship was speedily launched and equipped, the admiration of the naval world.
Shortly after the adoption of armor-plating as an essential feature in the construction of vessels of war, the
Southern States seceded from the
Union, some of the most efficient of the
United States naval officers resigning their commissions.
Their loss was severely felt by the Navy Department at
Washington; nor was it long before the presence of great professional skill among the officers of the naval administration of the
Confederate States became manifest.
Indeed, the utility of the armor-plating adopted by
France and
England proved to be better understood at
Richmond than at
Washington.
While the
Secretary of the Navy,
Mr. Welles, and his advisers were discussing the question of armor, news reached
Washington that the partly burnt and scuttled steam-frigate
Merrimac, at the
Norfolk Navy Yard, had been raised and cut down to her berth-deck, and that a very substantial structure of timber, resembling a citadel with inclined sides, was being erected on that deck.
The Navy Department at
Washington early in August advertised for plans and offers for iron-clad steam-batteries to be built within a stipulated time.
My attention having been thus called to a subject which I had thoroughly considered during a series of years, I was fully prepared to present plans of an impregnable steam-battery of light draught, suitable to navigate the shallow rivers and harbors of the
Confederate States.
Availing myself of the services of a friend who chanced to be in
Washington at the time, proposals
[
731]
were at once submitted to a board of naval officers appointed by the
President; and the plans presented by my friend being rejected by the board, I immediately set out for
Washington and laid the matter personally before its members, all of whom proved to be well-informed and experienced naval experts.
Contrary to anticipation, the board permitted me to present a theoretical demonstration concerning the stability of the new structure, doubt of which was the principal consideration which had caused the rejection of the plan presented.
In less than an hour I succeeded in demonstrating to the entire satisfaction of the board appointed by
President Lincoln that the design was thoroughly practical, and based on sound theory.
The
Secretary of the Navy accordingly accepted my proposal to build an iron-clad steam-battery, and instructed me verbally to commence the construction forthwith.
Returning immediately to New York, I divided the work among three leading mechanical establishments, furnishing each with detailed drawings of every part of the structure; the understanding being that the most skillful men and the best tools should be employed; also that work should be continued during night-time when practicable.
The construction of nearly every part of the battery accordingly commenced simultaneously, all hands working with the utmost diligence, apparently confident that their exertions would result in something of great benefit to the national cause.
Fortunately no trouble or delay was met at any point; all progressed satisfactorily; every part sent on board from the workshops fitted exactly the place for which it was intended.
As a consequence of these favorable circumstances, the battery, with steam-machinery complete, was launched in one hundred days from the laying of the keel-plate.
It should be mentioned that at the moment of starting on the inclined ways toward its destined element, the novel fighting-machine was named
Monitor.
J Before entering on a description of this
fighting-machine I propose to answer the question frequently asked: What circumstances dictated its size and peculiar construction?
- 1.
The work on the Merrimac had progressed so far that no structure of large dimensions could possibly be completed in time to meet her.
- 2.
The well-matured plan of erecting a citadel of considerable dimensions on the ample deck of the razed Merrimac admitted of a battery of heavy ordnance so formidable that no vessel of the ordinary type, of small dimensions, could withstand its fire.
- 3. The battery designed by the naval authorities of the Confederate States, in addition to the advantage of ample room and numerous guns, presented a 1
[732]
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.
- 4.
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.
- 5. The limited width of the navigable parts of the Southern rivers and inlets presented an obstacle rendering manoeuvring 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.
- 6. 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.
- 7. 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.
Several minor points familiar to the naval artillerist and naval architect presented considerations which could not be neglected by the constructor of the new battery; but these must be omitted in our brief statement, while the foregoing, being of vital importance, have demanded special notice.
The plans on pages 732-3 represent a longitudinal section through the center line of the battery, which, for want of space on the page, has been divided into three sections, viz., the aft, central, and forward sections, which for ready reference will be called
aft,
central,
and forward.
Referring particularly to the upper and lower sections, it will be seen that the hull consists of an upper and lower body joined together in the horizontal plane not far below the water-line.
The length of the upper part of the hull is 172 feet, beam 41 feet; the length of the lower hull being 122 feet, beam
 |
|
1.
aft section.
Longitudinal plan through the center line of the original monitor. |
[
733]
 |
|
2.
central section, same plan. |
34 feet. The depth from the underside of deck to the keel-plate is 11 feet 2 inches, draught of water at load-line 10 feet.
Let us now examine separately the three sectional representations.
Forward Section. The anchor-well, a cylindrical perforation of the overhanging deck, near the bow, first claims our attention.
The object of this well being to protect the anchor when raised, it is lined with plate iron backed by heavy timbers, besides being protected by the armor-plating bolted to the outside of the overhang.
It should be noticed that this method proved so efficient that in no instance did the anchor-gear receive any injury during the several engagements with the Confederate batteries, although nearly all of the monitors of the
Passaic class were subjected to rapid fire at short range in upward of twenty actions.
It will be remembered that the unprotected anchor of the
Merrimac was shot away during the short battle with the
Congress and the
Cumberland.
Having described the method of protecting the anchors, the mechanism adopted for manipulating the same remains to be explained.
Referring to the illustration, it will be seen that a windlass is secured under the deck-beams near the anchor-well.
The men working the handles of this mechanism were stationed in the hold of the vessel, and hence were most effectually protected against the enemy's shot, besides being completely out of sight.
The Confederate artillerists were at first much surprised at witnessing the novel spectacle of vessels approaching their batteries, then stopping and remaining stationary for an indefinite time while firing, and then again departing, apparently without any intervention of anchor-gear.
Our examination of this gear and the anchor-well affords a favorable opportunity of explaining the cause of
Lieutenant Greene's alarm, mentioned
 |
|
3.
forward section, same plan. |
[
734]
in a statement recently published by a military journal, concerning a mysterious sound emanating from the said well during the passage of the
Monitor from New York to
Fort Monroe.
Lieutenant Greene says that the sound from the anchor-well “resembled the death-groans of twenty men, and was the most dismal, awful sound [he ] ever heard.”
Let us endeavor to trace to some physical cause this portentous sound.
The reader will find, on close examination, that the chain cable which suspends the anchor passes through an aperture ( “a hawse-pipe” ) on the after side of the well, and that this pipe is very near the water-line; hence the slightest vertical depression of the bow will occasion a flow of water into the vessel.
Obviously, any downward motion of the overhang will cause the air confined in the upper part of the well, when covered, to be blown through the hawse-pipe along with the admitted water, thereby producing a very discordant sound, repeated at every rise and fall of the bow during pitching.
Lieutenant Greene also states that, apart from the reported sound, the vessel was flooded by the water which entered through the hawse-pipe ; a statement suggesting that this flooding was the result of faulty construction, whereas it resulted from gross oversight on the part of the executive officer,--namely, in going to sea without stopping the opening round the chain-cable at the point where it passes through the side of the anchor-well.
The pilot-house is the next important object represented in the forward section of the illustration now under consideration.
This structure is situated 10 feet from the anchor-well, its internal dimensions being 3 feet 6 inches long, 2 feet 8 inches wide, 3 feet 10 inches high above the plating of the deck; the sides consisting of solid blocks of wrought iron, 12 inches deep and 9 inches thick, firmly held down at the corner by 3-inch bolts passing through the iron-plated deck and deck-beams.
The wheel, which by means of ordinary tiller-ropes operates the rudder, is placed within the pilot-house, its axle being supported by a bracket secured to the iron blocks as shown by the illustration.
An ordinary ladder resting on the bottom of the vessel leads to the grated floor of the pilot-house.
In order to afford the
commanding officer and the pilot a clear view of objects before and on the sides of the vessel, the first and second iron blocks from the top are kept apart by packing pieces at the corners; long and narrow sight-holes being thereby formed extending round the pilot-house, and giving a clear view which sweeps round the entire horizon, all but that part which is hidden by the turret, hardly twelve degrees on each side of the line of keel.
Regarding the adequacy of the elongated sight-hole formed between the iron blocks in the manner described, it should be borne in mind that an opening of five-eighths of an inch affords a vertical view 80 feet high at a distance of only 200 yards. More is not needed, a fact established during trials instituted by experts before the constructor delivered the vessel to the
Government.
Unfortunately the sight-holes were subsequently altered, the iron blocks being raised and the opening between them increased to such an extent that at sea, to quote
Lieutenant Greene's report, the water entered “with such force as to knock the helmsman completely round from the wheel.”
It may be shown that but for the injudicious increase
[
735]
of the sight-holes, the commander of the
Monitor would not have been temporarily blinded during the conflict at
Hampton Roads, although he placed his vessel in such an extraordinary position that, according to
Lieutenant Greene's report, “a shell from the enemy's gun, the muzzle not ten yards distant [from the side of the
Monitor], struck the forward side of the pilothouse.”
The size of the sight-hole, after the injudicious increase, may be inferred from the reported fact that the blast caused by the explosion of the
Confederate shell on striking the outside of the pilot-house had the power of “partly lifting the top.”
This “top,” it should be observed, consisted of an iron plate two inches thick, let down into an appropriate groove, but not bolted down — a circumstance which called forth
Lieutenant Greene's disapprobation.
The object of the constructor
 |
|
Plan of the berth-deck of the original monitor, drawn to scale. |
a, captain's cabin;
b, his
state-room; c. state-rooms of the officers: w, wardroom;
d, quarters of the crew, with store-rooms on the sides.
in leaving the top plate of the pilot-house loose, so as to be readily pushed up from below, was that of affording egress to the crew in case of accident.
Had the monitor
Tecumseh, commanded by
Captain T. A. M. Craven, when struck by a torpedo during the conflict in
Mobile Bay, August 5th, 1864, been provided with a similar loose plate over the main hatch, the fearful calamity of drowning officers and crew would have been prevented.
In referring to this untoward event, it should be observed that means had been provided in all the sea-going monitors to afford egress in case of injury to the hull: an opening in the turret-floor, when placed above a corresponding opening in the deck, formed a free passage to the turret, the top of which was provided with sliding hatches.
Apparently the officer in charge of the turret-gear of
Captain Craven's vessel was not at his post, as he ought to have been during action, or else he had not been taught the imperative duty of placing the turret in such a position that these openings would admit of a free passage from below.
2
Lieutenant Greene's report with reference to the position of the pilot-house calls for particular notice, his assertion being that he “could not fire ahead within several points of the bow.”
The distance between the center of the turret and the pilot-house being fifty-five feet, while the extreme breadth of the latter is only five feet, it will be found that by turning the turret through an angle of only
six degrees from the center line of the vessel, the shot will clear the pilot-house, a structure too substantial to suffer from
[
736]
the mere aerial current produced by the flight of the shot.
Considering that the
Monitor, as reported by
Lieutenant Greene, was a “quick-turning vessel,” the disadvantage of not being able to fire over the bow within
six degrees of the line of keel is insignificant.
Captain Coles claimed for his famous iron-clad turret-ship the advantage of an all-round fire, although the axis of his turret-guns had many times greater deviation from the line of keel than that of the
Monitor.
The statement published by
Lieutenant Greene, that the
chief engineer of the vessel immediately after the engagement in
Hampton Roads “suggested the clever plan of putting the pilot-house on top of the turret,” is incorrect and calls for notice.
The obvious device of placing the pilot-house in the center and above the turret was carefully considered before the
Monitor turret was constructed, but could not be carried out for these reasons:
1. The turret of the battery was too light to support a structure large enough to accommodate the
commanding officer, the pilot, and the steering-gear, under the severe condition of absolute impregnability against solid shot from guns of 10-inch caliber employed by the
Confederates.
2. A central stationary pilot-house connected with the turret involved so much complication and additional work (see description of turret and pilothouses further on), that had its adoption not been abandoned the
Monitor would not have been ready to proceed to
Hampton Roads until the beginning of April, 1862.
The damage to the national cause which might have resulted from that delay is beyond computation.
The next important part of the battery delineated on the forward section of the illustration, namely, the quarters of the officers and crew, will now be considered; but before entering on a description it should be mentioned that in a small turret-vessel built for fighting, only one-half of the crew need be accommodated at a time, as the other half should be in and on the turret, the latter being always covered with a water-proof awning.
Referring again to the forward and to part of the central section, it will be seen that the quarters
 |
|
Transverse section of the hull of the original monitor.
The diagram gives a front view of the boilers and furnaces; also a side elevation of the rotating cylindrical turret which proved impregnable against ten-inch solid shot fired with battering charges at very short range. |
[
737]
 |
|
View showing the effect of shot on the “monitor” turret.
From a photograph taken soon after the engagement. |
The ridges shown in the nearer port are significant of the haste with which the vessel was built.
An opening of this shape is usually made by cutting three circles one above another and intersecting, and then trimming the edges to an oval.
In this instance there was no time for the trimming process.
Originally the armament was to be 15-inch guns, but as these could not be had in time, the 11-inch Dahlgrens were substituted.--editors.
extend from the transverse bulkhead under the turret to within five feet of the pilot-house, a distance of fifty feet; the forward portion, twenty-four feet in length, being occupied by the officers' quarters and extending across the battery from side to side.
The height of the aft part of these quarters is 8 feet 6 inches under the deck-beams; while the height of the whole of the quarters of the crew is 8 feet 6 inches. A. mere glance at the illustrations showing a side elevation [p. 733] and top view of internal arrangement [p. 735] gives a correct idea of the nature of the accommodations prepared for the officers and crew of the vessel which
Lieutenant Greene regards as a “crude” structure, and of which he says: “Probably no ship was ever devised which was so uncomfortable for the crew.”
If this opinion were well founded, it would prove that submerged vessels like the monitors are unfit to live in.
Fortunately, the important question whether crews can live permanently below water-line has been set at rest by the report of the chief of the Bureau of Medicine and Surgery to the
Secretary of the Navy, 1864.
This minute and carefully considered report enabled the naval administration, organized by
President Lincoln, to prove the healthfulness of the monitors, by the following clear presentation of the subject: “The monitor class of vessels, it is well known, have but a few inches of their hulls above the water-line, and in a heavy sea are entirely submerged.
It has been doubted whether under such circumstances it would be possible long to preserve the health of the men on board, and consequently maintain the fighting material in a condition for effective service.
It is gratifying, therefore, to know that an examination of the sick-reports, covering a period of over thirty months, shows that, so far from being unhealthy, there was less sickness on board the monitors than on the same number of wooden ships with an equal number of men and in
[
738]
similar exposed positions.
The exemption from sickness upon the iron-clads in some instances is remarkable.
There were on board the
Saugus, from November 25th, 1864, to April 1st, 1865, a period of over four months, but four cases of sickness (excluding accidental injuries), and of these two were diseases with which the patients had suffered for years.
On the
Montauk, for a period of one hundred and sixty-five days prior to the 29th of May, 1865, there was but one case of disease on board.
Other vessels of the class exhibit equally remarkable results, and the conclusion is reached that no wooden vessels in any squadron throughout the world can show an equal immunity from disease.”
Apart from the ample size of the quarters on board the vessel, shown by the illustration, it should be mentioned that the system adopted for ventilating those quarters furnishes an abundant supply of fresh air by the following means.
Two centrifugal blowers, driven by separate
steam-engines, furnished seven thousand cubic feet of atmospheric air per minute by the process of suction through standing pipes on deck.
Part of the air thus drawn in supported the combustion of the boiler furnaces, the remainder entering the lower part of the hull, gradually expelling the heated and vitiated air within the vessel.
It has been imagined that the fresh air supplied by the blowers ought to have been conveyed to the quarters at the forward end of the vessel, by a system of conducting pipes.
The laws of static balance, however, render the adoption of such a method unnecessary, since agreeably to those laws the fresh cold air, unless it be stopped by closed doors in the bulkheads, will find its way to every part of the bottom of the hull, gradually rising and expelling the upper heated strata through the hatches, and lastly through the grated top of the turret.
Naval constructors who speculate on the cause of the extraordinary healthfulness of the monitors need not extend their researches beyond a thorough investigation of the system of ventilation just described.
Turret Department. The most important object delineated on the
central section of the illustration, namely, the rotating turret, will now be considered; but before describing this essential part of the monitor system, it will be well to observe that the general belief is quite erroneous that a revolving platform, open or covered, is a novel design.
So far from that being the case, this obvious device dates back to the first introduction of artillery.
About 1820 the writer was taught by an instructor in fortification and gunnery that under certain conditions a position assailable from all sides should be defended by placing the guns on a turntable.
Long before building the
Monitor I regarded the employment of a revolving structure to operate guns on board ships as a device familiar to all well-informed naval artillerists.
But although constructors of revolving circular gun-platforms for naval purposes, open or covered, have a right to
 |
|
Side elevation of a floating revolving circular tower, published by Abraham Bloodgood in 1807. |
[
739]
 |
|
Floating circular citadel, submitted to the French directory in 1798. |
employ this ancient device, it will be demonstrated further on that the turret of the monitors is a distinct mechanical combination differing from previous inventions.
The correctness of the assumption that revolving batteries for manipulating guns on board floating structures had been constructed nearly a century ago will be seen by the following reference to printed publications.
The
Nautical Chronicle for 1805 contains an account of a “movable turning impregnable battery, invented by
a Mr. Gillespie, a native of
Scotland, who completed the model of a movable impregnable castle or battery, impervious to shot or bombs, provided with a cannon and carriage calculated to take a sure aim at any object.”
It is further stated that “the invention proposed will be found equally serviceable in floating batteries.
Its machinery is adapted to turn the most ponderous mortars with the greatest ease, according to the position of the enemy.”
Again, the Transactions of the Society for the Promotion of Useful Arts in the
State of New York, 1807, contains an illustration representing a side elevation of a circular revolving floating battery constructed by
Abraham Bloodgood.
The guns of this battery, as the inventor points out, “would be more easily worked than is common, as they would not require any lateral movement.”
It is also stated, as a peculiar feature of this floating battery, that “its rotary motion would bring all its cannon to bear successively, as fast as they could be loaded, on objects in any direction” ; and that “its circular form would cause every shot that might strike it, not near the center, to glance.”
Thirty-five years after the publication of the illustration and description of the circular floating revolving tower of
Abraham Bloodgood,
Theodore R. Timby proposed to build a tower on land for coast defense, to be composed of iron, with several floors
[
740]
 |
|
Side elevation and transverse section (through the center line of its revolving semi-spherical turret) of an iron-clad steam-battery, plans of which were submitted by Captain Ericsson to Napoleon III.
in September, 1854. |
and tiers of guns, the tower to turn on a series of friction-rollers under its base.
The principal feature of
Timby's “invention” was that of arranging the guns radially within the tower, and firing each gun at the instant of its coming in line with the object aimed at during the rotary motion of the tower, precisely as invented by
Bloodgood.
About 1865 certain influential citizens presented drawings of
Timby's revolving tower to the authorities at
Washington, with a view of obtaining orders to build such towers for coast defense; but the plan was found to be not only very expensive, but radically defective in principle.
The slides of the gun-carriages being fixed permanently in a radial direction within the tower, the guns, of course, are directed to all points of the compass.
Hence, during an attack by a hostile fleet, with many ships abreast, only one assailant can be fired at, its companions being scot-free in the dead angle formed between the effective gun and the guns on either side.
In the meantime the numerous guns, distributed round the tower on the several floors, cannot be fired until their time comes during the revolution of the tower.
The enemy's fleet continuing its advance, of course, calls for a change of elevation of the pieces, which, considering the constant revolution of the tower and the different altitudes above the sea of the several tiers, presents perplexing difficulties.
Nothing further need be said to explain why the
Government did not accept the plans for
Timby's revolving towers.
The origin of rotating circular gun-platforms being disposed of, the consideration of the central section of the illustration will now be resumed.
It will be seen that the turret which protects the guns and gunners of the
Monitor consists simply of a short cylinder resting on the deck, covered with a grated iron roof provided with sliding hatches.
This cylinder is composed of eight thicknesses of wrought-iron plates, each one inch thick, firmly riveted together, the inside course, which extends below the rest, being accurately faced underneath.
A flat, broad ring of bronze is let into the deck, its upper
[
741]
face being very smooth in order to form a water-tight joint with the base of the turret without the employment of any elastic packing, a peculiar feature of the turrets of the monitors, as will be seen further on. Unfortunately, before the
Monitor left New York for
Hampton Roads, it was suggested at the
Navy Yard to insert a plaited hemp rope between the base of the turret and the bronze ring, for the purpose of making the joint perfectly water-tight.
As might have been supposed, the rough and uneven hemp rope did not form a perfect joint; hence during the passage a great leak was observed at intervals as the sea washed over the decks.
“The water came down under the turret like a waterfall,” says
Lieutenant Greene in his report.
It will be proper to observe in this place that the “foundering” of the
Monitor on its way to
Charleston was not caused by the “separation of the upper and lower part of the hull,” as was imagined by persons who possessed no knowledge of the method adopted by the builders in joining the upper and lower hulls.
Again, those who asserted that the plates had been torn asunder at the junction of the hulls did not consider that severe strain cannot take place in a structure nearly submerged.
The easy motion at sea, peculiar to the monitors, was pointed out by several of their commanders.
Lieutenant Greene in his report to the
Secretary of the Navy, dated on board the
Monitor, March 27th, 1862, says with reference to sea-going qualities:
During her passage from New York her roll was very easy and slow and not at all deep.
She pitched very little and with no strain whatever.
 |
|
Isaac Newton, first assistant-engineer of the “monitor.”
from a medallion portrait by Launt Thompson.
At the time of Mr. Newton's death (September 25, 1884) he had been for several years Chief Engineer of the Croton Aqueduct.
The plans which have been adopted for the new aqueduct were his, both in the general features and the details.-editors. |
Captain John Rodgers's report to the
Secretary of the Navy, dated on board of the monitor
Weehawken, January 22d, 1863, refers specially to the easy motion of his vessel:
On Tuesday night, when off Chincoteague shoals, we had a very heavy gale from the E. N. E. with a very heavy sea, made confused and dangerous by the proximity of the land.
The waves I measured after the sea abated; I found them twenty-three feet high.
They were certainly seven feet higher in the midst of the storm.
During the heaviest of the gale I stood upon the turret and admired the behavior of the vessel.
She rose and fell to the waves, and I concluded that the monitor form had great sea-going qualities.
If leaks were prevented no hurricane could injure her.
The true cause of the foundering of the
Monitor was minutely explained to the writer some time after the occurrence by the engineer, a very intelligent person, who operated the centrifugal pumping-engine of the vessel at the time.
According to his statement, oakum was packed under the base of the turret before going to sea, in order to make sure of a water-tight joint; but this expedient failed altogether, the sea gradually washing out the oakum in those places where it had been loosely packed, thereby permitting so large a
[
742]
 |
|
Transverse section of the “monitor” through the center of the turret. |
quantity of water to enter under the turret, fully sixty-three feet in circumference, that the centrifugal pumping-engine had not sufficient power to expel it. The hull consequently filled gradually and settled, until at the expiration of about four hours the
Monitor went to the bottom.
It will be asked, in view of the preceding explanation of the construction of the monitor turrets, namely, that the smooth base of the turret forms a water-tight joint with the ring on the deck, why was oakum packed under the turret before going to
Charleston?
The commander of the vessel,
Captain Bankhead, in his report of the foundering, adverts to the admission of water under the turret, but does not duly consider the serious character of the leak, sixty-three feet in length.
Captain Bankhead evidently had not carefully investigated the matter when he attributed the accident to an imaginary separation of the upper and lower hull.
3 It should be observed, in justice to this officer, that having commanded the
Monitor only during a brief period he possessed but an imperfect knowledge of his vessel, and probably knew nothing regarding the consequence of employing packing,--namely, that it might cause “water to come down under the turret like a waterfall,” as previously reported by the second officer in command.
It is proper to mention as a mitigating circumstance in favor of the second officer,
Lieutenant Greene, that previous to the battle in
Hampton Roads he had “never performed any but midshipman duty.”
The important question, therefore, must remain unanswered, whether in the hands of an older and more experienced executive officer the
Monitor, like the other vessels of her type, might not have reached
Charleston in safety.
Referring again to the central part of the illustration [p. 733] and the sectional representation of the turret [above], it will be found that the guns are
[
743]
placed across the vessel; consequently only the end of the breech and upper part of the port-hole are seen.
The object of the pendulum port-stoppers suspended under the roof is to afford protection to the turret crew while loading the guns.
Generally, however, the turret should be moved, and the port-holes thereby turned away from the enemy.
Much time was lost during the conflict with the
Merrimac by closing the port-stoppers in place of merely moving the turret, the latter operation being performed by a small steam-engine controlled by a single hand; while opening and closing the port-stoppers, as reported by
Lieutenant Greene, required the entire gun-crew.
The slow fire of the
Monitor during the action, complained of by critics, was no doubt occasioned by an injudicious manipulation of the port-stoppers.
There are occasions, however, when the turret should not be turned, in which case the port-stoppers are indispensable.
The method adopted for turning the turret will be readily understood.
The small steam-engine controlled by one man, before referred to, drives a double train of cog-wheels connected with the vertical axle of the turret, this axle being stepped in a bronze bearing secured to the central bulkhead of the vessel.
The mechanism thus described was carefully tested before the
Monitor left New York for
Hampton Roads, and was found to move very freely, the turret being turned and the guns accurately pointed by the sailing-master without aid. The trouble reported by
Lieutenant Greene regarding the manipulation of the turret was caused by inattention during the passage from New York, the working-gear having been permitted to rust for want of proper cleaning and oiling while exposed to the action of salt-water entering under the turret, from causes already explained, Having thus briefly described the turret and its mechanism, our investigation of the central part of the sectional view of the battery will be completed by a mere reference to the steam-boilers placed aft of the turret.
There are two of these boilers placed side by side, as shown in the cut on page 736. Two views being thus presented, the nature of the boilers will be understood without further explanation.
It should be mentioned, however, that they proved very economical and efficient.
Aft Section. The following brief reference to this section of the sectional illustration, showing the motive engine, propeller, and rudder, will complete our description:
1. The motive engine, the construction of which is somewhat peculiar, consists of only one steam-cylinder with pistons applied at opposite ends, a steam-tight partition being introduced in the middle.
The propeller-shaft has only one crank and one crank-pin, the difficulty of “passing the centers” being overcome by the expedient of placing the connecting-rods, actuated by the steam-pistons, at right angles to each other.
Much space is saved within the vessel by employing only one steam-cylinder, an advantage of such importance in the short hulls of the monitors that the entire fleet built during the war was provided with engines of the stated type.
2. The propeller, being of the ordinary four-bladed type, needs no description; but the mode of protecting it against shot demands full explanation.
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Referring to the illustration, it will be seen that the under side of the overhang near the stern is cut out in the middle, forming a cavity needed to give free sweep to the propeller-blades; the slope of the cavity on either side of the propeller being considerably inclined in order to favor a free passage of the water to and from the propeller-blades.
3. The extreme beam at the forward side of the propeller-well is 31 feet, while the diameter of the propeller is only 9 feet; it will therefore be seen that the deck and side armor projects 11 feet on each side, thus protecting most effectually the propelling instrument as well as the equipoise rudder applied aft of the same.
It will be readily admitted that no other vessel constructed here or elsewhere has such thorough protection to rudder and propeller as that just described.
The foregoing description of the hastily constructed steam-battery proves that, so far from being, as generally supposed, a rude specimen of naval construction, the
Monitor displayed careful planning, besides workmanship of superior quality.
Experts who examined the vessel and machinery after completion pronounced the entire structure a fine specimen of naval engineering.
The conflict in
Hampton Roads, and the immediate building of a fleet of sea-going monitors by the United States Government, attracted great attention in all maritime countries, especially in the north of
Europe.
Admiral Lessoffsky, of the
Russian navy, was at once ordered to be present during the completion and trial of our sea-going monitors.
The report of this talented officer to his government being favorable, the
Emperor immediately ordered a fleet of twelve vessels on the new system, to be constructed according to copies of the working-drawings from which the
American sea-going monitors had been built.
Sweden and
Norway also forthwith laid the keels of a fleet of seven vessels of the new type,
Turkey rapidly following the example of the northern
European nations.
It will be remembered that during the naval contest on the
Danube the
Russian batteries and torpedo-boats subjected the Turkish monitors to severe tests.
England, in due course, adopted our turret system, discarding the turn-table and cupola.
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Sinking of the “monitor,” December 29, 1862. |
