+------------------+----------------------------------------+---------+
| NAME OF SHIP. | Armament. | Cost. |
| | | |
+------------------+----------------------------------------+---------+
| _Armored._ | Main. Secondary. | Dollars.|
|Puritan | 4 of 10 inch} |2,300,970|
|Miantonomoh | 4 ” 10 ” } |1,637,110|
|Amphitrite | 4 ” 10 ” } |1,590,930|
|Monadnock | 4 ” 10 ” } |1,592,849|
|Terror | 4 ” 10 ” } |1,891,077|
| |{2 ” 6 ” } Not determined. | |
|Battle-ship |{2 ” 10 ” } |2,500,000|
| |{2 ” 12 ” } | |
| | } | |
|Cruiser |{4 ” 10 ” } |2,500,000|
| |{6 ” 6 ” } | |
| _Unarmored._ | | |
| |{4 ” 8 ” } 2 6-pdrs., 4 47 mm., | |
|Chicago |{8 ” 6 ” } 2 37 mm. |1,576,854|
| |{2 ” 5 ” } 2 1-pdrs., 2 short Gat. | |
| | | |
|Boston |{2 ” 8 ” } 2 6-pdrs., 2 3-pdrs., 2 |1,031,225|
| |{6 ” 6 ” } 1-pdrs. | |
| | | |
|Atlanta |{2 ” 8 ” } 2 47 mm., 2 37 mm., 2 |1,031,225|
| |{6 ” 6 ” } short Gatlings. | |
| | | |
|Dolphin | 1 ” 6 ” } 2 6-pdrs., 4 47 mm., 2 | 460,000|
| | } Gatlings. | |
| | | |
| | Auto-mobile torpedoes. | |
|Charleston |{2 ” 10 ” } 4 6-pdrs., 2 3-pdrs., |1,017,500|
| |{6 ” 6 ” } 1 1-pdr., *Amt | |
| | | |
|Baltimore |{4 ” 8 ” } 4 37 mm., 2 short |1,325,000|
| |{8 ” 6 ” } Gatlings, *Amt | |
| | | |
|Newark |12 ” 6 ” } *Amt |1,300,000|
| | | |
|Gun-boat No. 1 | 6 ” 6 ” } 2 6-pdrs., 2 3-pdrs., | 455,000|
| | } 1 1-pdr., *Amt | |
| | | |
|Gun-boat No. 2 | 4 ” 6 ” } 2 37 mm., 2 short | 247,000|
| | } Gatlings, *Amt | |
| | | |
|Dynamite cruiser |{3 ” 10½ ” } 2 3-pdrs., 1 1-pdr., | 350,000|
| |{ (Dynamite.) } 2 37 mm., 2 short Gat. | |
| | | |
|Cruiser No. 4 |12 ” 6 ” } Not yet determined. |1,500,000|
|Cruiser No. 5 |12 ” 6 ” } |1,500,000|
| | | |
|Gun-boat No. 3 | 6 ” 6 ” } Same as Gun-boat | 550,000|
|Gun-boat No. 4 | 6 ” 6 ” } No. 1. | 550,000|
| | | |
|Torpedo-boat | .... } 2 rapid-fire guns. | 100,000|
| | } 5 torpedoes. | |
| | | |
|Stiletto | .... } Not yet determined. | 25,000|
|Floating batteries| .... } |2,000,000|
+------------------+----------------------------------------+---------+
*Amt = Auto-mobile torpedoes.
Thanks to the force of public opinion, liberal appropriations
have been made for the navy. Leaving out of consideration the
double-turreted Monitors, the additions to the fleet have been the
cruisers _Charleston_ and _Baltimore_, the No. 1 and 2 gun-boats,
the cruiser _Newark_, the two armored vessels, the torpedo-boat,
the dynamite cruiser, the No. 4 and 5 cruisers, the No. 3 and 4
gun-boats of No. 1 type, and the floating batteries. The _Stiletto_,
if accepted, will be bought from the Herreshoff Company; all the
rest, except the battle-ship, are to be or have been constructed by
contract in private yards. Of the new ones the _Charleston_ and No. 5
cruiser will be built at San Francisco; gun-boat No. 2 at Baltimore;
the dynamite cruiser, gun-boat No. 1, the _Baltimore_, _Newark_, and
cruiser No. 4, at Philadelphia, and gun-boats Nos. 3 and 4 at New
York.
The steel partially protected cruiser _Charleston_ is, except in
details of internal accommodations, a duplicate of the _Naniwa-Kan_,
which was in turn a progressive development of the type-making
_Esmeralda_, inasmuch as she has greater speed, more powerful
armament, and superior protection to stability. The plans of the
_Charleston_ were bought abroad simply because they could not be
made here; and notwithstanding the twopenny-ha’penny criticisms this
action evoked, its wisdom has been justified. The _Charleston_ has
neither poop nor forecastle, and the unhampered ends give in action
perfect freedom of fire for two 10-inch guns, which are mounted in
low, thin-plated barbettes, situated on the ship’s middle line, at
a distance of sixty feet from the bow and stern respectively. These
pieces are without armor protection, except that offered against
machine-gun fire by a two-inch segmental shield. Between these
heavy guns a high waist stretches amidships, in which six 6-inch
breech-loaders are mounted on sponsons or in projecting turrets.
The secondary battery includes two 6-pounder rapid-fire guns, eight
machine guns, and four above-water torpedo-tubes. The 10-inch guns
must always be brought back to the fore-and-aft line for reloading,
and their ammunition is passed through steel tubes which extend below
the protective deck. The engines are double-compound, situated in
separate compartments, and in the _Naniwa-Kan_ the type developed
7650 horse-power and 18.9 knots.
In the twin-screw cruiser _Baltimore_ a longitudinal water-tight
bulkhead joins the double bottom, which runs under the engine and
boilers to a protective deck that extends the whole length of the
ship, and is three inches thick on the flat top and four inches
thick on the sloping sides. The machinery consists of a pair of
triple-expansion compound engines which are to develop 18 knots and
7500 horse-power with natural, and 19½ knots and 10,750 horse-power
with forced, draft. There are two separate engine-rooms and two
boiler-rooms, and the normal coal capacity of 600 tons will be
sufficient for 1800 knots. Additional space is provided for 300 tons
more, and with this total there ought to be an endurance of 8000
miles at 11 knots, and of 14,000 miles, or 75 days’ steaming, at 8
knots. No sails except storm-sails will be provided. The _Baltimore_
is to have a poop and forecastle, on which four 8-inch guns with
direct fore-and-aft fire will be mounted. On the main deck six 6-inch
guns will be carried in broadside, and the secondary battery and
torpedo-tubes are effective and well disposed.
The maximum price fixed at first by Congress for the _Newark_ was
less than any of the bids received, but at the last session the
appropriation was increased to $1,300,000, and the contract was
awarded in August of this year. The _Newark_ is a bark-rigged,
twin-screw cruiser of 4083 tons displacement. A double bottom extends
through 129 feet of her length, and a protective deck, which rises
fifteen inches above the water-line amidships, runs uninterruptedly
fore and aft. Four feet above this the berth-deck is built, the
intermediate space being greatly subdivided and utilized for stores.
Numerous water-tight frames are worked in the double bottom, and
wherever practicable the cellular construction is employed. The
engines are to develop 6000 horse-power with natural draft, and
8500 horse-power and a maximum speed of eighteen knots with forced
draft. This vessel has a poop and forecastle, and the guns are
carried on the upper deck. The main battery consists of twelve
6-inch centre-pivot guns, furnished with segmental shields, and
mounted on sponsons so as to obtain the greatest arc of fire; the
two guns nearest the bow and stern converge their fire at a point
400 feet distant from the ends of the ship, and those in broadside
can be concentrated within 100 feet of the ship. In addition to
the secondary battery given in the table, there are six above-water
torpedo-tubes.
The development of naval construction cannot be proved more
conclusively than by comparing the new cruisers with those which
were first laid down. In the _Atlanta_, for example, the builder
guaranteed that 664 tons of machinery would produce 3500 indicated
horse-power; but the _Charleston_ must, before acceptance, develop
7000 horse-power for 710 tons of machinery; that is to say, the
energy for weight has been doubled within four years.
The twin-screw gun-boat No. 1 is the prototype of a class that now
include three vessels, and a very promising nucleus it is for a
fleet to which the defence of the country’s coast must mainly be
intrusted. The ship is to be built of steel, with a three and a half
inch complete water-tight deck, so arched as to have a spring of
about three feet in its greatest width, and a crown that will nearly
reach the water-line level. There is no double bottom, but the number
of water-tight compartments is very great, and coffer-dams surround
the engine and fire-room hatches, and are carried to a height of
eighteen inches above the main deck. The complement numbers 150, and
the rig is that of a three-masted schooner, with a sail area of 4400
square feet. The machinery is estimated to indicate 2200 horse-power
with natural draft, and 3300 with forced draft, and consists of two
independent compound engines placed in separate compartments. The
speed is given as sixteen knots, but it is probable this rate will be
considerably exceeded. The main battery consists of six 6-inch guns,
the secondary of two 57-millimetre rapid-fire guns, two 37-millimetre
revolving cannons, and one short Gatling. Four of the 6-inch guns are
mounted on the poop and forecastle—two forward, two aft—and the
other pieces of this calibre are carried on sponsons amidships, so
as to have a large arc of fire about the beam. The elevated guns are
eighteen feet above the low-water line, the centre ones ten feet, and
all are mounted on central pivots and fitted with protective shields.
The torpedo armament is of great relative importance; of the eight
tubes supplied, the stem and stern ones are fixed and fitted with
under-water discharge, while the other six can be trained, and are
distributed four forward and two aft. In gun-boat No. 2 the machinery
is to develop 900 horse-power with natural, and 1350 with forced,
draft; the engines, boilers, and magazines are placed beneath a steel
deck three-eighths of an inch thick, which amidships is twenty-seven
inches below the water-line at the edge and eight inches above at the
crown. The armament consists of four 6-inch sponson-mounted guns, two
47-millimetre guns, two 37-millimetre revolving cannons, and one
short Gatling. She is barkentine rigged, with a plain sail area of
4480 square feet, and has a slightly ram-shaped, cast-steel stem. The
complement is 100.
The pneumatic-gun cruiser is to be armed with three of Zalinski’s
pneumatic dynamite guns of 10½-inch calibre, each of which is to
throw a shell containing 200 pounds of high explosives for a distance
of one mile, and to be capable of being discharged at least once in
two minutes. The guaranteed speed is twenty knots.
Under the law of August 3, 1881, authorizing the construction of
two new ships, it was provided that these should be “sea-going,
double-bottomed, armored vessels of about 6000 tons displacement,
designed for a speed of at least sixteen knots an hour, with engines
having all necessary appliances for working under forced draft, to
have a complete torpedo outfit, and be armed in the most effective
manner.” According to the circular issued by the Navy Department,
one of these was to be an armored cruiser, with a maximum draught
of twenty-two feet, and the other a battle-ship, with a draught
of twenty-three feet; both were to be built of steel, with double
bottoms, to have numerous water-tight compartments fitted with
powerful pumping apparatus, and to be supplied throughout with
perfect drainage and ventilation. A ram bow, twin screws, electric
search-lights, torpedo outfit, and a protected steel-armored deck
running the whole length of the ship and covering the boilers,
engines, and magazines, were essentials; while high power and economy
were so equally demanded that, to a maximum maintained speed of
seventeen knots when fully equipped, great coal endurance and small
fuel consumption were to be added. In each vessel a space sufficient
for two hundred and seventy people, for provisions for three months,
and for water for one month, was required. The cruiser was to have
two-thirds sail-power on two or three masts, each supplied with a
military top fitted to mount one or more machine guns. The armament
of this ship was to include ten steel breech-loading rifles—four of
10-inch and six of 6-inch calibre—and a secondary battery of four
6-pounders, four 3-pounders, and two 1-pounders, rapid-fire, and four
47-millimetre and four 37-millimetre revolving cannons, all of the
Hotchkiss pattern, together with four Gatling guns. There were to be
fitted six torpedo-tubes—one bow, one stern, and two on each side,
of which at least one on each side forward was to be under water.
The heavy guns were to load in not less than two positions, and were
to be protected by at least ten and a half inches of steel armor,
properly backed; the 6-inch guns were to be fitted with shields,
and all the guns were to be arranged so as to obtain the greatest
horizontal and vertical fire consistent with other conditions. Any
vertical armored protection at the water-line was to be at least
eleven inches thick in the heaviest part, and thicker, if practicable.
The armament of the line-of-battle ship was to consist of two 12-inch
and six 6-inch guns, and of a secondary battery which included four
6-inch, six 3-pounder, and two 1-pounder rapid-fire guns; of four
47-millimetre and four 37-millimetre revolving cannons, and of four
Gatlings. The torpedo outfit was similar to that of the cruiser.
The plans submitted were opened on April 1st of this year, and
notwithstanding the difficulties which the displacement imposed
upon the other requirements, no less than thirteen designs were
received from ten different competitors. The most important of
these were offered by the Thames Iron Ship Building Company and the
Barrow Ship Building Company, of Great Britain; by A. H. Grandjean,
Esq., of France; and by Chief Constructor Wilson, Naval Constructor
Pook, and Lieutenant Chambers, all of the United States navy. The
designs were submitted to a board, and this finally recommended the
Barrow plan as best suited for the armored battle-ship. So far as
the armored cruiser was concerned, the Board reported as follows:
“The marked differences in the essential features of the designs of
armored cruisers of the Barrow Ship Building Company, Lieutenant W.
I. Chambers, A. H. Grandjean, and the Thames Iron-Works and Ship
Building Company, prevent their classification in the order of merit.
Each exhibits features which strongly commend themselves, but the
Board does not consider it advisable for the government to build a
vessel upon any one of these plans.”
The battle-ship, though designed by one of the most distinguished
marine architects in England, has not in its present form received
the general approval of experts, for between it and the plan
submitted by the Bureau of Construction there seem to be differences
of merits which are strongly in favor of the latter. The dimensions
of the new ships are as follows:
BARROW SHIP.
Length between perpendiculars, 290 feet; on load water-line, 300
feet; extreme breadth, 64 feet 1 inch; mean draught, 22 feet 6
inches; displacement, 6300 tons.
NAVY DEPARTMENT SHIP.
Length between perpendiculars, 300 feet; on load water-line,
310 feet; extreme breadth, 58 feet; mean draught, 22 feet;
displacement, 6600 tons.
The striking differences between these two ships are found in their
relative stability and sea-going qualities. Mr. John, the designer
of the Barrow ship, in a paper on “Atlantic Steamers,” read before
the Institution of Naval Architects July 29, 1886, made the following
statements:
“This question of stability will have to be carefully watched and
studied within the next few years, because there is a tendency at
present towards a rapid increase in the proportion of beam to length;
and as the draught of water in these large ships is limited, we must
be careful that in seeking higher speeds with increased beam we do
not get too much stability, and so render the vessels heavy rollers
and very uncomfortable as passenger-ships. It is possible the future
may see vessels of greater beam than any yet afloat in the merchant
service; but if so, it is almost inevitable that they will have to be
made higher out of water in order to render them easy and comfortable
at sea, but even that has its limits. Perhaps it is well to give
an extreme case, and here I will make use of our old friend _The
Great Eastern_.... Now, for the purpose of trading it is quite clear
that _The Great Eastern_ cannot be loaded much deeper than other
ships, while her beam is half as great again; and the consequence
is, her stability, as compared with our modern passenger-ships, is
so excessive that she is bound to be a tremendous roller among the
heavy seas in the Atlantic. Her metacentric height, when loaded, was,
I believe, stated by the late Mr. Froude to be as much as 8.7 feet,
which is from three to four times as much as is thought sufficient
for ships in the present day, or consistent with their easy behavior
at sea.”
Thus Mr. John himself regards 2.9 feet to 2.2 feet as the proper
metacentric height for those steamers, and it is generally considered
by modern designers that from 2.5 to 3.2 feet is most suitable for
this class of armored ships, and is conducive to easiness of motion
in a sea-way. The value of this quality to a ship intended for
sea-fighting cannot be overestimated, for upon her steadiness as a
gun-platform the aim and efficiency of her guns greatly depend.
It will be noticed that this ship has exceptionally great beam,
that of most ships of her class and displacement, varying from 54
to 59 feet, and judging from the sketches which have appeared, her
water-line coefficient is about 0.72. From an approximate calculation
based on this assumption it is found that her metacentric height
will be about six feet. The water-line coefficient may possibly be
a little finer than 0.72, and thus reduce the metacentric height,
but if this ship is assumed to have a metacentric height of three
feet, her water-line coefficient would be 0.6288, which is an
_impossibility_, if her coefficient of fineness of displacement
be that given in the published dimensions. Such a water-line and
coefficient of fineness for 6300 tons displacement would produce
a perfect rectangle for a midship section. So that, unless her
dimensions are changed, she will surely be a heavy roller, and after
much sea duty she will suffer such severe strains as to require
frequent and costly repairs.
The battle-ship designed at the Navy Department has very different
qualities, if the dimensions already published be correct. To possess
a metacentric height of three feet she would require a water-line
coefficient of 0.753, and a midship-section coefficient of 0.89 to
0.90, which is a good proportion for such a vessel. Not only in
sea-going qualities does the American design seem to be superior,
but her battery is far more powerful and better disposed in every
way, while her speed and endurance are equally as great as the plan
recommended. Mr. John has adopted the _échelon_ arrangement of heavy
guns, a disposition which both the English and Italian governments
have, after long trial, discarded in their latest ships. When the
first sketches of a design are made, this arrangement of guns is
theoretically perfect, as it is supposed to give quite as much power
of fire ahead and astern as on each broadside; but when the design is
developed and practically tested, it is found that too much of the
ship’s efficiency in other respects is sacrificed, that the powerful
end fire is not attained, and that the broadside is greatly weakened,
owing to the obstructed arcs of fire.
Besides this, the guns, being placed at some distance from the
midship line, have less accurate fire in rolling, and the ship’s
propensities to roll are encouraged and are greater than would be the
case if the guns were placed on the midship line. It is also found
that the blast from the heavy guns is destructive to superstructures
and other fittings on the upper deck. The Italians, indeed, have
placed stout ventilating shafts on their _Italia_ and _Lepanto_ to
prevent the rearmost pair of heavy guns from being trained within
twenty degrees of the fore and aft line. This is done so that the
blast from these guns will not prostrate the gunners attending the
other pair, notwithstanding the fact that those men are under the
armor cover. The _Duilio’s_ forward smoke-pipe is placed entirely
on the port side of the fore and aft line, in order to permit of
one pair of turret guns firing ahead. The upper-deck, 6-inch,
central-pivot guns of the _Andrea Doria_ class are now to be placed
wholly within the superstructure, in order to be out of danger from
the blast of the heavy guns when the latter are fired near the
line of keel, and the same change would have to be made with the
upper-deck, 6-inch guns in the Barrow design.
Similar objections exist to the Bureau of Construction design for an
armored cruiser. This vessel, although possessing the bad features
inherent in the _échelon_ arrangement of heavy guns, does not have
the best ideas of the Barrow design, _i.e._, high freeboard, heavy
guns mounted high above the water-line, and commodious quarters for
officers and men. Both designs besides have the very objectionable
and old-fashioned features of requiring the turrets to be revolved
to fixed loading positions after being fired. The Bureau cruiser, it
may be said, is not saddled with too much metacentric height. She has
ten feet less beam, her centre of gravity is about one foot lower,
and unless her water-line coefficient is very full, she will have a
metacentric height rather less than what is regarded to be the best.
It is not surprising, however, that the Bureau plans are so different
in efficiency, for while the better plan, the battle-ship, is
original with the Navy Department, the armored cruiser is a copy
of, and no substantial improvement over, that of the Brazilian ship
_Riachuelo_ designed several years ago. This ship is considered one
of the best of her date, but great improvements in ship design have
been made within the past few years, and it is against the tendencies
of American inventive genius to take a step backward.
The general plans of cruisers No. 4 and 5 were published in the _New
York Herald_ of June 1st, together with the following data:
“They are to be twin-screw cruisers, 310 feet long on the water-line,
49 feet 1¾ inches extreme breadth, 18 feet 9 inches mean draught,
displacing 4083 tons. They are to have machinery of 10,500 indicated
horse-power under forced draft. The maximum speed is 19 knots, rig
that of a three-masted schooner, spreading 5400 square feet of sail.
They will have a double bottom extending through 129 feet of the
length. The framing in this portion is on the bracket system. Before
and abaft the double bottom, above the protective deck, Z-bars form
the transverse frames. The protective deck, which is nineteen inches
above the water-line amidships, is flat across the top, with sides
which slope down to a depth of four feet three inches below the
water-line. The horizontal portion is two inches thick, the slope
being three inches, reduced at both ends to one and a half inches. It
extends uninterruptedly forward and aft, and protects the machinery,
magazines, and steering-gear, the machinery being further defended by
the disposition of the coal-bunkers. The main hatches in this deck
are protected by armor-bars, and have coffer-dams extending to the
upper deck. The guns are carried on the gun, forecastle, and poop
decks.
“_Armament._—The main battery, which consists of twelve 6-inch
breech-loading rifles, all on centre-pivot mounts, with two-inch
segmental steel shields, is arranged on sponsons so as to obtain
the greatest possible arc of fire. The forecastle, the poop, and
the bridges have been as much as possible availed of to shelter
the guns. The two guns forward and the two guns aft converge their
fire a short distance from the ends of the ship, and the broadside
can be concentrated within 100 feet of the side. Four above-water
torpedo-tubes are provided on the berth-deck, and two direct ahead
under-water torpedoes in the bow. The secondary battery is composed
of four 47-millimetre revolvers, four 57-millimetre single-shots, two
37-millimetre revolvers, and one short Gatling. The coal capacity is
850 tons. The complement of men 300....
“To appreciate what is required to make nineteen knots an hour at
sea, we have only to remember that the _Umbria_ and _Etruria_ are
500 feet long, with more than 12,000 tons displacement and 14,500
indicated horse-power, ordinarily making 18½ and on special occasions
19 knots an hour. Now, to increase her speed to 20 knots an hour,
the _Umbria_ would require about 19,500 horse-power, which means
5000 extra horse-power for the extra knot. For a second extra knot
would be required about 6000 horse-power more, making about 25,000
horse-power necessary to develop a speed of 21 knots.”
Gun-boats Nos. 3 and 4 are to be copies of gun-boat No. 1. No designs
for the floating batteries and the torpedo-boat have been published.
The _Stiletto_ is one of the famous Herreshoff boats, and is now
being tested in consequence of a favorable report made by a board of
officers. On July 23, 1886, with a total displacement of twenty-eight
tons, she made an average of 22.12 knots as the mean of four runs
over the measured mile in a rough sea and fresh wind, and on July
30th she attained an average of 22.89 knots. These were excellent
results for a boat ninety feet in length, and promised that the
type, with certain modifications, was equal to greater demands. The
trial data of this year have not yet been published, though it is
unofficially reported that her performance was equally as creditable.
UNITED STATES NAVAL ARTILLERY.
From the time of the introduction of cast-iron cannons in 1558 until
a comparatively late period, development in naval artillery proceeded
at a very slow rate. The security that was attained by the adoption
of cast-iron was so great, as compared with the danger attending the
use of the more ancient artillery, that the new guns were regarded as
fully supplying all the demands of a suitable battery. The guns were
muzzle-loaders, making the manipulation simple, the previous rude
attempts at breech-loading being abandoned. The number of calibres
that were introduced was very numerous, partly to suit the weight of
the batteries to the ships, and partly to accommodate the fancy of
the time for placing in different parts of the ships guns varying
much in size and destructive effect. The general character of the
batteries and the multiplication of calibres can best be illustrated
by noting the armament of two typical ships of the seventeenth
century.
[Illustration: BRONZE BREECH-LOADING CANNON CAPTURED IN COREA, AGE
UNKNOWN.]
The _Royal Prince_, a British ship built in 1610, carried
fifty-five guns. Of these, two were _cannon-petronel_, or
24-pounders; six were _demi-cannon_, medium 32-pounders; twelve were
_culverins_, 18-pounders, which were nine feet long; eighteen were
_demi-culverins_, nine-pounders; thirteen were _rakers_, 5-pounders,
six feet long; and four were _port-pieces_, probably swivels.
These guns were disposed as follows: on the lower gun-deck, two
24-pounders, six medium 32-pounders, and twelve 18-pounders; on
the upper gun-deck the battery was entirely of 9-pounders; and the
forecastle and quarter-deck were armed with 5-pounders, and the brood
of smaller pieces which swelled the nominal armament.
The _Sovereign of the Seas_, built in 1637, in the reign of Charles
I., was unequalled by any ship afloat in her time. She mounted on
three gun-decks eighty-six guns. On the lower deck were thirty long
24-pounders and medium 32-pounders; on her middle deck, thirty
12-pounders and 9-pounders; on the upper gun-deck, “other lighter
ordnance;” and on her quarter-deck and forecastle, “numbers of
murdering pieces.”
In the obstinately contested actions between Blake and Van Tromp in
the Cromwellian time, the ships and batteries did not differ in any
great degree from those contemporaneous in construction with the
_Sovereign of the Seas_; and when we remember the inferior character
of the powder used in those days we can account for the duration of
some of the engagements between the English and Dutch ships which
were sometimes protracted through three days.
[Illustration: BRONZE BREECH-LOADER USED BY CORTEZ IN MEXICO.]
The brood of “murdering pieces” of small calibre and little energy
was, after many years, dispersed by the introduction of carronades—a
short cannon of large calibre, which was found to be a convenient
substitute for the 8-pounders and 9-pounders on upper decks, and for
the “lighter ordnance,” which was ineffective; but this change was
brought about slowly, as is seen by referring to the batteries of
some ships which fought at Trafalgar.
The Spanish seventy-fours in that action had fifty-eight long
24-pounders on the gun-decks; on the spar-deck, ten iron 36-pounder
carronades and four long 8-pounders; and on the poop, six iron
24-pounder carronades—total, seventy-eight guns.
[Illustration: BREECH-LOADER CAPTURED IN THE WAR WITH MEXICO.]
The _Victory_, the English flag-ship, mounted on her three gun-decks
ninety long 32, 24, and 12 pounders, and on the quarter-deck and
forecastle, ten long 12-pounders and two 68-pounder carronades.
The _Santissima Trinidada_ mounted on the lower gun-deck thirty long
36-pounders; on the second deck, thirty-two long 18-pounders; on
the third deck thirty-two long 12-pounders; and on the spar-deck,
thirty-two 8-pounders. In the British accounts she is said to have
had one hundred and forty guns, which number must have included
swivels mounted for the occasion.
At the end of the eighteenth century the 18-pounder was the preferred
gun for the main-deck batteries of frigates, guns of larger calibre
being found only on the lower decks of line-of-battle ships. The
18-pounder was the maximum calibre that was employed on board the
ships of the United Colonies of North America in the war of the
Revolution. The resources of the colonies did not admit of building
ships to contend with vessels fit to take their place in line of
battle, but such as were constructed were well adapted to resist the
small British cruisers, and to capture transports and store-ships.
The so-called frigates of that day were vessels varying from six
hundred to a thousand tons, and, according to their capacity, carried
12-pounders or 18-pounders in the main-deck batteries. There was
usually no spar-deck, but the forecastle and quarter-deck, which were
connected by gangways with gratings over the intermediate space,
were provided with an armament of light 6, 9, or 12 pounders. A few
carronades came into use during this war.
At the conclusion of this war the Colonial fleet disappeared, and it
was not until the time of the depredations on the growing commerce
of the United States by the Algerine corsairs that Congress felt
justified in incurring the expense of establishing a national marine.
The ships which were built under the law of 1794 were fully up to
the most advanced ideas of the time, and some of these ships carried
on their gun-decks a full battery of 24-pounders, thirty in number,
while the others were armed with 18-pounders on the gun-deck, with
spar-deck batteries of 9 and 12 pounders, the carronade not having
been yet definitely adopted for spar-deck batteries.
It is not until the war of 1812 that we find the carronade fully
established as the spar-deck armament of frigates. The _Constitution_
and the _Guerrière_ carried 32-pounder carronades of very similar
weight and power in the place of the long guns of smaller calibre on
the spar-deck. The original name of this piece of ordnance was the
“Smasher,” the leading purpose of the inventor, General Melville,
of the British artillery, being to fire 68-pounder shot with a low
charge, thus effecting a greater destruction in a ship’s timbers
by the increased splintering which this practice was known to
produce. Carronades of small calibre were subsequently cast, which
were adopted for spar-deck batteries of frigates and line-of-battle
ships, and, as they grew in favor, formed the entire battery of
sloops-of-war and smaller vessels until about 1840, when the
attention that had been given for some years to the subject of naval
ordnance began to assume tangible shape, and the effort was made to
proceed in this matter in accordance with an intelligent system.
[Illustration: BRONZE 12-POUNDER, “EL NEPTUNO,” 1781.]
The advantage of large calibre was firmly impressed upon those who
occupied themselves with the ordnance matters of the navy. As the
fleet was developed, the 24-pounder gave way to the 32-pounder, and
for the lower-deck battery of line-of-battle ships the 42-pounder
was introduced. Some 42-pounder carronades were also introduced as
spar-deck batteries for these larger ships. With the disappearance of
this class of ship the 42-pounder was abandoned, and the 32-pounder
was retained as the maximum calibre, different classes being assigned
to different sizes of ships. These classes were divided into the gun
proper, with 150 pounds of metal to one of shot; the double-fortified
gun, with 200 pounds of metal to one of shot; and the medium gun,
with 100 pounds of metal to one of shot. The carronade of the same
calibre, mounted on a slide, had a proportional weight of 65 pounds
of metal to one of shot.
[Illustration: U.S.N. CARRONADE, SLIDE, AND CARRIAGE.]
In the interval between 1840 and 1845 the double-fortified 32-pounder
was replaced by a gun of the same calibre of 57 hundred-weight,
called the long 32-pounder; and to suit the capacity of the different
classes of ships then in the service, there were introduced
the 32-pounders of 46 hundred-weight, 42 hundred-weight, and
27 hundred-weight, in addition to the regular medium gun of 32
hundred-weight. This period also marks the introduction of shell-guns
as part of the battery.
To this time no explosive projectiles had been used with cannons
properly so called; their use had been limited to mortars and
howitzers. The mortar was originally used for projecting huge balls
of stone at high angles. The first practical use made of them
for projecting bombs was in 1624, but the unwieldy weight of the
mortar and its bomb, the latter sometimes exceeding 300 pounds,
prevented their use in field operations. To provide for this, light
mortars were cast, which, being mounted on wheels, were denominated
howitzers. Frederick the Great of Prussia brought this form of
artillery to its highest development for field and siege use, and
the Continental powers of Europe adopted it to a large extent for
projecting bombs at high angles of fire. The mortar has never had
a place in regular naval armaments; it has been used afloat for
bombardment of cities and fortified positions, but never with a view
to contending with ships.
[Illustration: U.S.N. MEDIUM 32-POUNDER.]
The success attending the use of explosive projectiles at high
elevations did not lead at once to their application to horizontal
firing from cannons. An important link in the progress of the idea
resulted from the effort to avail of the advantage of ricochet firing
with bombs. In order to effect this, the angle of elevation had to
be reduced to enable the bomb to roll along the ground. The reduced
angle of elevation was still greater than that used for cannon, but
the success of the experiment led to the casting by the French of an
8-inch siege howitzer, which, in connection with the development in
the manufacture of fuses, made it practicable to apply the idea of
firing shells, like shot, horizontally, and the chief object in view
seems to have been to operate against ships.
The combining of the elements necessary for the achievement of this
important step in naval artillery is by common consent credited to
General Paixhan, of the French artillery, who, though not claiming
the invention of any of the numerous details involved in the system,
succeeded in so judiciously arranging the parts as to make the system
practicable by which the whole character of naval armaments was
revolutionized.
Following the progressive ideas of the age, shell-guns were
introduced in the United States navy. These were of 8-inch calibre,
and of weights of 63 hundred-weight and 55 hundred-weight. The
guns were shaped in accordance with the form adopted by General
Paixhan, and were easily distinguishable in the battery from the
ordinary shot-gun. From this circumstance they obtained the title of
Paixhan-guns, though there was nothing special in the gun itself to
merit an appellation. The whole system was Paixhan’s; the gun was
only a part of the system.
It required many years to bring the shell-gun into such general
application as to displace the solid-shot gun. They were assigned
tentatively to ships in commission, and in 1853, by a navy
regulation, the battery of a frigate was provided with only ten of
these guns, which were collected in one division on the gun-deck. The
first vessel in the United States navy whose battery was composed
exclusively of shell-guns was the sloop-of-war _Portsmouth_, in 1856.
This vessel carried a battery of sixteen 8-inch shell-guns of 63
hundred-weight. These were among the first of a new pattern of gun
for which the navy is indebted to the skill and study of the late
Rear-admiral Dahlgren.
The determination of the best form for cannons was a question which
had occupied the minds of artillerists for some years. In the older
guns the thickness of metal was badly distributed; it was too
uniformly extended along the entire length, not arranged in such
proportions as to accord with the differing strains along the bore.
Colonel Bumford, of the United States Ordnance, had been among the
first to consider this subject, and for many years the results of
his experiments had guided construction to a great degree. General
Paixhan made a further step in advance by reducing very much the
thickness of metal along the chase of his guns, but it remained for
Rear-admiral Dahlgren to produce the perfection of form in the gun
so widely known bearing his name. In this gun the thickness of metal
is proportioned to the effort of the gases in the bore, and all
projections and angular changes of form are suppressed, giving to
all parts a curved and rounded surface. The suppression of angular
formations on the exterior of a casting has a remarkable effect
on the arrangement of the crystals while cooling. These arrange
themselves normal to the cooling waves, which, if entering from
directions not radial with the cylindrical casting, produce confusion
in their arrangement, establishing planes of weakness where the waves
meet, which, in case of overstrain on the piece, assist rupture and
determine the course of the fracture.
With the introduction of the Dahlgren shell-gun the transition of
the artillery of the United States navy may be said to have been
completed. The shell-gun of 9-inch and 11-inch calibres followed the
8-inch, and ships were armed with such as were appropriate to their
capacity as rapidly as the new guns could be manufactured. When fully
equipped, the armament of the United States navy was superior to that
of any other navy in the world.
The substitution of shells for solid shot marks an important epoch in
naval artillery. The probable effect of a shot could be predetermined
and provided for; that of a shell was unknown. In order to produce
serious injury with a shot, it was necessary to perforate the side
of an enemy. This was not indispensable with a shell; with the
latter, perforation might be dispensed with, as penetration to such
a depth as would give efficacy to the explosion might prove more
destructive to the hull than would absolute perforation. With the
shot, damage was done to life and material in detail; with the shell,
if successfully applied, destruction was threatened to the entire
fabric, with all it contained. Naval artillery entered a new phase;
the rough appliances of the past would no longer answer all demands.
The founder could not alone equip the battery; the laboratory was
called into use, and pressed to provide from its devices. The “new
arm” depended upon the successful working of the fuse of the shell,
without which it was but a hollow substitute for a solid shot, and
this detail demanded the utmost care in preparation. It was the
perfecting of this device which, more than aught else, delayed the
general adoption of the new artillery for so long a time after its
advantages had been recognized.
[Illustration: U.S.N. 9-INCH DAHLGREN (9-INCH SMOOTH-BORE).]
The fuses that were used to explode the ancient bombs were long
wooden plugs, bored cylindrically, and filled with powder condensed
by tamping it to a hard consistency. The fuse case projected from the
bomb, and to avoid being bent by the shock of discharge, was placed
carefully in the axis of fire. Before the discharge of the mortar
the fuse was lighted by a match. In applying the fuse to shell-guns
fired horizontally, the problem was so to arrange it as to ignite
it by the flame of discharge, and so to support it in the wall of
the shell as to prevent any dislocation of the fuse composition, the
cracking of which would permit the penetration of the flame into
the mass. This was successfully accomplished, and the United States
navy fuse was justly famous, one feature of it being a simple but
most effective device called a “water-cap,” which guarded against
the injurious introduction of sand or water when the shell was fired
_en ricochet_. The introduction of a safety-plug in the bottom of
the fuse case, which required the shock of discharge to displace it
in order to open a way of communication between the fuse and the
bursting charge in the shell, and the absence of all accidents in
manipulation, inspired such confidence that the new arm advanced to
favor, and both officers and men were proud to be identified with it.
Previous to the introduction of shells there had been in use
incendiary projectiles, not explosive, but intended to set fire to an
enemy’s vessel. Hot shot were applied to this purpose, but the use
of these was chiefly confined to shore batteries, where a suitable
heating furnace could be conveniently provided. The projectile for
this purpose chiefly used from ships was the carcass, which was a
shot in which several radial cylindrical holes were formed which
were filled with powder tamped to a hard consistency; these columns
of composition were ignited by the flame of discharge, and continued
to burn until consumed. The flame issuing from these holes served to
ignite consumable material in their vicinity. The chief danger from
a carcass was from lodgment in the side of a ship; if it landed on
deck it could be removed and thrown overboard, as there was no danger
from explosion; the addition of the bursting charge in the cavity
of a shell produced a projectile which was far in advance both for
generating a flame and for preventing interference with its mission.
The probable destructive effect of shells exploding in the sides
or on the open decks of ships was thoroughly recognized, and
experiments at targets sufficiently proved it; but circumstances on
a proving-ground and in action are so dissimilar that the experience
of a naval engagement was looked forward to with much interest, in
order to satisfy as to the effect of the new projectile in all the
varying conditions of a sea-fight. Referring to the history of the
past thirty years, which marks the period of the general introduction
of shell-guns, it is remarkable how few engagements between ships
have taken place; but on every occasion of the use of shells, when
unarmored vessels were engaged, the effect has been most decided
and complete. Three instances only can be referred to of purely
sea-fights, _viz._, the engagement between the Russian and Turkish
fleets at Sinope in 1853, during the Crimean war, the engagement
between the United States steamer _Hatteras_ and the Confederate
cruiser _Alabama_ during the war of the rebellion, and the fight
between the _Kearsarge_ and the _Alabama_ during the same war. In
the affair at Sinope the Russian ships used shells; the Turkish had
only solid shot. The result was the total destruction of the Turkish
force. Not one ship escaped; all were burned or sunk. The fight
between the _Alabama_ and the _Hatteras_ resulted in the sinking
of the _Hatteras_; and the contest between the _Alabama_ and the
_Kearsarge_ ended the career of the _Alabama_. And it may be noticed
that but for the failure to explode of a shell that was embedded in
the stern-post of the _Kearsarge_, that vessel might have accompanied
her antagonist to the bottom of the sea.
The gallant attempt of Rear-admiral Lyons with the British wooden
fleet before the forts of Sebastopol is an instance which proved the
uselessness of subjecting unarmored vessels to the steady fire of
fortified positions using shells from their batteries.
One other instance of a sea-fight can be cited in the engagement in
1879 between two Chilian armored vessels and the lightly armored
Peruvian turreted vessel _Huascar_. The _Huascar_ was terribly
over-matched during this fight, but at its conclusion her boilers and
engines were intact, and indentations on her sides showed that her
light armor had deflected a number of projectiles; but the effect of
the shells that had burst on board of her was apparent in the great
destruction of life.
The very decisive engagement which took place at Lissa in 1866,
between the Austrian and Italian fleets, should not be omitted in
alluding to sea-fights of a late period; but this action can hardly
be quoted as one in which the element of shell-fire can be recognized
as the exclusive cause of destruction, for the remarkable impetuosity
and dash of the attack and the desperate use of the ram produced a
crisis which obviated the necessity for continuous bombardment with
cannon.
The necessity of providing a defence against shells was recognized
both by England and France during the Crimean war, and a protection
of armor was supplied to some floating batteries built at that time
which were intended to operate before fortified positions; and at the
conclusion of the war the English built the _Warrior_ and the French
built _La Gloire_. These were the first specimens of iron-clad ships
of war. They were capable of resisting successfully the entrance
of shells from guns of the period. It is thus seen that almost
coincident with the general adoption of horizontal shell-firing,
naval construction entered a new phase, and a new problem was
submitted to the naval artillerist.
Against an iron-faced target the solid shot might be partially
effective, but the impact of the spherical shell was harmless, and
the explosive effect of the bursting charge enclosed in it would be
superficial. This was amply demonstrated in actual practice during
our war experience, notably at Mobile Bar, in the engagement with the
Confederate iron-clad _Tennessee_, the roughly constructed armor of
which vessel resisted a storm of our heaviest shells.
[Illustration: HORIZONTAL SECTION OF MILLWALL SHIELD.]
The impotency of the spherical shell against armor being recognized
by foreign governments, they proceeded to develop the rifled
cannon, which with its elongated projectile offered the means
of effecting the object of the time—to perforate armor with an
explosive projectile. Our authorities, however, persevered in their
faith in the smooth-bore, and held that the _racking_ effect of a
spherical projectile of sufficiently large calibre was superior to
that produced by the perforation of a rifle projectile of inferior
diameter. The 15-inch and 20-inch smooth-bore cannons were cast in
accordance with this idea, and the racking side of the question was
so obstinately held that the British government imported in 1867 from
the United States a 15-inch gun for the purpose of determining by
their own experiments what foundation there was for the advantages
that were claimed for it. The gun was bought of Charles Alger & Co.,
of Boston; it weighed nineteen tons, and threw a cast-iron spherical
solid shot of about four hundred and fifty pounds. It was mounted
at Shoeburyness, and was fired in competition with English rifled
cannons of 9-inch and 10-inch calibres. The result of the experiments
went to show that against a target with a power of resistance
inferior to the energy of the projectile the effect of the large
sphere at short range is more disastrous than that of the elongated
rifle projectile of the same weight; but that against a target able
to resist the total energy of both the injury done by the rifle
projectile is by far the greater. The comparative effect is well
shown on a target called the “Millwall Shield,” consisting of a plate
nine inches in thickness, backed by Hughes’s hollow stringers—an
arrangement of target which to the time of the experiment had proved
invincible. The 15-inch smooth-bore spherical shot rebounded from the
target six feet, leaving a 3-inch indentation on the plate, while the
9-inch rifle projectile, weighing two hundred and fifty pounds, made
complete penetration of the plate, passing two or three inches into
the backing, and the 10-inch rifle projectile, weighing four hundred
pounds, penetrated to the rear of the backing itself.
It should be mentioned in this connection that the United States
government adopted during the war of the rebellion a rifled cannon
proposed by Captain Parrott of the West Point Foundery, New York, of
which many were introduced into both the navy and army, and did good
service as long as the charges of powder were limited in weight; but
when these guns were called upon for work requiring great endurance,
they proved untrustworthy and dangerous to those who served them.
At the naval bombardment of Fort Fisher several of them burst,
causing loss of life on board the vessels of which they formed the
armament. They were constructed of cast-iron, having a coiled hoop
of wrought-iron shrunk around the breech. They have ceased to form a
part of our naval armament.
During the years of inaction in the United States that have
intervened since these experiments, the smooth-bore partisans have
had time to reflect and to learn lessons of practical usefulness from
observing what has been transpiring abroad. Opportunities have been
afforded to note the progress made in armor and artillery, and though
the smooth-bore shell is still operative against unarmored vessels,
the advantages of the rifled gun under all the circumstances of navy
experiences have been admitted, and in the transition through which
our naval artillery is now passing we are not embarrassed by the
presentation of views antagonistic to the principles on which it has
been determined our new artillery is to be constructed. The system
at the basis of our present acts is founded on a comprehensive view
of the whole subject, and is intended to provide our ships with a
surplus of offensive power over what their capacity for defence might
seem to call for.
Our navy will possess a certain number of armored vessels for coast
defence, and armored sea-cruisers are certain to be included in
the list, but the more numerous class will be unarmored, and the
first problem to be solved is that of providing for these a suitable
armament.
[Illustration: A KRUPP GUN ON A NAVAL CARRIAGE.]
The work to be done by an unarmored cruiser must be done from a
distance when risking an engagement with an armored enemy. The
superiority of armament must compensate for deficiency in defensive
power which precludes close quarters. To make these ships effective
they must be armed with guns capable of doing an extraordinary amount
of work, and yet the size of the vessels will not admit of their
carrying guns of immense weight. In order to get this amount of
work out of a comparatively light gun, we must secure great initial
velocity for the projectile. This can only be done by burning a large
charge of powder, which involves a long bore in which to burn it,
while care is necessary to secure a large margin of strength in the
material of which the gun is constructed. These essential demands
required a radical change in the form and material of our present
armament; they also forced a change in the method of construction.
[Illustration: ALFRED KRUPP.]
The superior fitness for cannons of steel over cast-iron was
recognized many years ago, but the difficulty of casting steel
in large masses prevented the introduction of steel guns, and
the generally acceptable treatment of cast-iron made it answer
satisfactorily the demands for gun-metal not subjected to unusual
strains. Mr. Frederick Krupp, of Essen, in Germany, was the first
steel manufacturer who succeeded in casting steel in large masses,
and he produced a number of steel guns cast from crucibles in solid
ingots, which were bored, turned, and fashioned as in the case of
cast-iron smooth-bore guns. These guns held a position in advance
of other manufactures on the score of strength of material. But the
introduction of the rifle system, the call for higher velocities, the
increased charges of powder, with the consequent increase of strain,
enhanced by the friction attending the passage of the projectile
forced along the bore, had the effect of calling attention to the
weakness that was inherent in the method of construction of cannons.
It is well known that an explosive force operating in the interior
of a hollow cylinder of any thickness is not felt equally throughout
the wall of metal; the parts near the seat of explosion are called
upon to do much more work in restraining the force generated than are
the parts more remote. It has been determined that the strain brought
upon the portions of the wall is in inverse proportion to the squares
of their distances from the seat of effort. Thus, in a gun cast
solid, if we take a point two inches from the bore, and another four
inches from the bore, the strain felt at those points respectively
will be inversely in the proportion of four to sixteen, or, in other
words, the metal at two inches from the bore will be strained four
times as much as that at the distance of four inches. From this it
can be seen that the metal near the seat of effort may be strained
beyond its tensile strength, while that more distant is only in
partial sympathy with it. Rupture thus originates at the interior
portion, and the rest of the wall yields in detail. No additional
strength of material can change this relationship between the parts;
they result from a law, and show that this method of construction
for a cannon is untrustworthy where the strains approach the tensile
strength of the material.
The means of providing against this successive rupture of
over-strained parts is found in the “built-up gun,” in which an
interior tube is surrounded by encircling hoops of metal, which are
shrunk on at sufficient tension to compress the portions which they
enclose. This is the principle of “initial tension,” which is the
basis of the modern construction of cannons. By adopting this method,
an ingot to form a tube to burn the required amount of powder can be
cast of a light weight in comparison with what would be needed for
a complete gun, and the strength and number of reinforcing rings to
be shrunk around it can be readily determined, proportioned to the
known strain that will be brought upon the bore of the piece. The
late developments in the manufacture of steel by the open-hearth
process remove all difficulty to procuring the necessary metal in
masses suitable for all parts of the heaviest guns.
[Illustration: BREECH-LOADING RIFLE-TUBE READY FOR RECEIVING JACKET.]
The built-up steel gun is the one now adopted in Europe by the
leading powers, and it is the gun with which the United States navy
will be armed; but, before its final adoption, efforts were made to
convert old smooth-bore cast-iron guns into rifles, and to construct
new guns partially of steel and partly of wrought-iron. As some of
these methods of conversion offered an economical means of acquiring
rifled cannons, our naval authorities were led into the error of
countenancing the effort to a moderate degree.
[Illustration: BREECH-LOADING RIFLE-JACKET, ROUGH-BORED AND TURNED.]
The system that was adopted was that originally suggested by Mr.
P. M. Parsons in England, which was afterwards patented by Major
Palliser, R.A., and bears his name. It consisted in enlarging the
bore of a cast-iron gun, and inserting a tube of wrought-iron formed
of a bar arranged in the form of a coil when heated. The tube was
expanded by firing charges of powder, and afterwards rifled. The guns
are muzzle-loaders, and are not increased in length beyond that of
the cast-iron gun which forms the casing for the tube. The length is
thus limited in order to preserve the preponderance of the piece,
and because of the want of longitudinal strength in the coil, which
cannot be depended on beyond a few tons’ strain; the arrangement of
metal in a coil provides very well for circumferential or tangential
strains, but in the Palliser conversion the longitudinal strength
depends on the cast-iron casing. The idea of the coiled wrought-iron
tube originated with Professor Treadwell, of Harvard University, in
1841. He utilized it by enclosing a tube of cast-iron or steel in
the same manner as it is applied in the wrought-iron Armstrong and
Woolwich guns.
[Illustration: PUTTING THE JACKET ON A 6-INCH BREECH-LOADING
RIFLE-TUBE.]
The administration of our naval ordnance has abandoned conversions,
and has concentrated its efforts on the production of an armament
of built-up steel guns. The system of construction that has been
adopted originated in England, but was for many years ignored by
the government authorities. It involved the use of steel in all its
parts, and this was charged as an objection, as confidence in this
metal was not established in the minds of the English artillerists.
That government committed itself entirely to the wrought-iron gun
proposed by Mr. (now Lord) Armstrong, whose system was a reproduction
of that successfully experimented on by Professor Treadwell, and the
entire force of the government works at Woolwich and of the Armstrong
works at Elswick-on-the-Tyne was occupied with the production of this
style of ordnance. The English steel gun invented by Captain Blakely
and Mr. J. Vavasseur was ignored in England, but its merit could not
be suppressed, and its superiority has forced a tardy recognition by
that government.
This gun came prominently into notice for a short time at the
breaking out of the war of the rebellion: some guns were imported
for the service of the Southern States. At the exhibition in London
in 1862 a Blakely 8.5-inch gun was one of the features of attraction
in the department of ordnance. The principle of the construction
was shown in this gun, consisting in shrinking a long jacket of
steel around an enclosed steel tube, the jacket extending to the
trunnions. Mr. Vavasseur was the manager of the London Ordnance
Works, and was associated with Captain Blakely in the manufacture of
his earlier guns, but the entire business soon fell into the hands
of Mr. Vavasseur, whose name alone is associated with the succeeding
developments of the gun.
In 1862 the guns manufactured by Mr. Krupp were solid forgings. He
advanced but slowly towards the construction of built-up cannons, and
it was not until the failure of some of his solid-cast guns that he
entered on the built-up system. His first steps were to strengthen
the rear portion of new guns by shrinking on hoops, and to increase
the strength of old guns he turned down the breech and shrunk on
hoops. He confined this system of strengthening to the rear of the
trunnions until he was reminded of the necessity of strength along
the chase of the gun by the blowing off of the chase of some 11-inch
guns of his manufacture. His system was then modified so as to
involve reinforcing the tube of the larger calibred guns along its
whole length with hoops, and his later and largest productions are
provided with a long jacket reinforcing the entire breech portion of
the tube—a virtual adoption of the great element of strength which
has always formed the essential feature in the Vavasseur gun which is
now adopted in the United States navy.
In the building up of the steel gun for the navy advantage is so
taken of the elastic characteristic of the metal that all parts tend
to mutual support. The gun proper consists of a steel tube and a
steel jacket shrunk around it, reaching from the breech to and beyond
the location of the trunnion-band. Outside the jacket and along the
chase of the gun there are shrunk on such hoops as the known strain
on the tube may make necessary for its support. The tube is formed
from a casting which is forged, rough-bored, and turned, and then
tempered in oil, by which its elasticity and tensile strength are
much increased. It is then turned on the exterior, and adjusted to
the jacket, the proper difference being allowed for shrinkage. The
jacket, previously turned and tempered, is then heated, and rapidly
lowered to its place. The front hoops over the chase are then put
on, and the gun is put into a lathe and turned to receive the
trunnion-band and rear and front hoops. The gun is then fine-bored
and rifled.
[Illustration: BREECH-LOADING RIFLE AFTER RECEIVING JACKET.]
Each part, as successively placed in position, is expected to
compress the parts enclosed through the initial tension due to
contraction in cooling. This tension is the greater the farther the
part is removed from the tube; thus the jacket is shrunk on at a less
tension than are the encircling hoops. By this means full use is
made of the elastic capacity of the tube which contributes the first
resistance to the expanding influence of the charge. The tension of
the jacket prevents the tube being forced up to its elastic limit,
and it in turn experiences the effect of the tension of the other
encircling parts which contribute to the general support; thus no
part is strained beyond its elastic limit, and on the cessation
of the pressure all resume their normal form and dimensions. A
comparison of this method of common and mutual support of parts with
that given by the wall of a gun cast solid will serve to demonstrate
the superior strength of the construction. In order to achieve this
intimate working of all the parts it is necessary that the metal
of which they are respectively composed must be possessed of the same
essential characteristics; in a word, the gun must be homogeneous.
It was the absence of this feature in the Armstrong gun which has
caused its abolition. This gun was built up, and the parts were
expected to contribute mutual support, but the want of homogeneity
between the steel tube and the encircling hoops of wrought-iron made
it impossible for them to work in accord, in consequence of the
different elastic properties of the two metals, which, after frequent
discharges, resulted in a separation of surfaces between the tube and
hoops, when the tube cracked from want of support.
[Illustration: A KRUPP HAMMER.]
[Illustration: TRANSPORTING CANNON AT BREMERHAVEN.]
In the construction of the guns for the United States navy, as in
the new steel guns now being manufactured in England, the theory
of the built-up system is practically conformed to; more so than by
Krupp or the French artillerists, who use a thicker tube than is
considered judicious at Woolwich or at the Washington navy-yard. Any
increase of thickness of the tube beyond what is necessary to receive
the initial pressure of the charge is open to the objections made to
the gun with a solid wall, the proportion of the strain communicated
to the hoops is reduced, and rupture may ensue from overstraining
the tube. The thicker the tube, the less appreciable must be the
compression induced by the tension of the encircling hoops.
[Illustration: BREECH-LOADING RIFLE AFTER RECEIVING JACKET AND CHASE
HOOPS.]
[Illustration: BREECH-LOADING RIFLE WITH JACKET, CHASE HOOPS, AND
JACKET HOOPS IN PLACE.]
The gun is a breech-loader. The system adopted for closing the
breech is an American invention (see note, p. 257), but having
been employed in France from the earliest experimental period, it
is known as the French _fermeture_. A screw is cut in the rear end
of the jacket to the rear of the tube, and a corresponding screw
is cut upon a breech-plug. The screw threads are stripped at three
equidistant places, the screw and plane surfaces alternating, thus
forming what is called an “interrupted” or “slotted” screw. The screw
portions of the breech-plug enter freely along the plane longitudinal
surfaces cut in the tube, and being then turned one-sixth of its
circumference, the screw of the plug locks in that of the tube, and
the breech is closed.
[Illustration: U.S.N. 6-INCH BREECH-LOADING RIFLE.]
The success of this system of breech mechanism was not so pronounced
on its introduction as it is to-day. The plug forms the base of the
breech of the gun, and all the effort of the gases to blow out the
breech is exerted at this point. The impact upon the end of the plug
is very severe, and has a tendency to _upset_ the metal, thereby
increasing the diameter of the plug, which would prevent its removal
after the discharge of the piece. With quick-burning powder, as was
generally in use for cannons at the inception of the breech-loading
experiments, this result ensued if the charges of powder were carried
above a certain limit, and the consequent restriction that was
put upon velocities was a serious obstacle to the adoption of the
system; but the progress that has been made of late years in the
science of gunpowder manufacture has relieved the subject from this
embarrassment, powder being now provided which communicates very high
velocities while developing pressures so moderate and regular as to
be entirely under the control of the artillerist.
The original guns, four in number, constructed with breech mechanism
on the French _fermeture_ principle for the British government during
the Crimean war are now in the “Graveyard” at Woolwich Arsenal.
The projectiles for the new armament are of two kinds; both, however,
are shells. That for ordinary use against unarmored vessels is
styled the common shell, and is of cast-iron. The length bears a
uniform proportion to the gun, being in all cases three and a half
calibres. The armor-piercing shell is made of forged steel, and is
three calibres in length. The following table gives the particulars,
approximately, of the common shell:
+------------------------------+------------------+--------+---------+
| GUN. | Length. | Weight.| Bursting|
| | | | Charge. |
+------------------------------+--------+---------+--------+---------+
| | Inches.| Calibre.| Pounds.| Pounds. |
| 5 inch breech-loading rifle | 17.97 | 3.59 | 60 | 2 |
| 6-inch breech-loading rifle | 20.90 | 3.48 | 100 | 4 |
| 8-inch breech-loading rifle | 28.10 | 3.51 | 250 | 12 |
| 10 inch breech-loading rifle | 35.00 | 3.50 | 500 | 22 |
| 12 inch breech-loading rifle | 42.00 | 3.50 | 850 | 38 |
| 16-inch breech-loading rifle | 56.00 | 3.50 | 2000 | 90 |
+------------------------------+--------+---------+--------+---------+
The armor-piercing shell of the same weight is reduced in length,
and its walls are thicker; the bursting charge is consequently much
reduced. The following are the particulars, approximately determined:
+------------------------------+------------------+--------+---------+
| GUN. | Length. | Weight.| Bursting|
| | | | Charge. |
+------------------------------+--------+---------+--------+---------+
| | Inches.| Calibre.| Pounds.| Pounds. |
| 5-inch breech-loading rifle | 15.07 | 3.01 | 60 | 1 |
| 6-inch breech-loading rifle | 17.91 | 2.98 | 100 | 1.50 |
| 8-inch breech-loading rifle | 24.25 | 3.03 | 250 | 3.50 |
| 10-inch breech-loading rifle | 30.00 | 3.00 | 500 | 7 |
| 12-inch breech-loading rifle | 36.00 | 3.00 | 850 | 14 |
| 16-inch breech-loading rifle | 48.00 | 3.00 | 2000 | 30 |
+------------------------------+--------+---------+--------+---------+
The rifle motion is communicated by one rotating ring of copper,
which is placed at the distance of 1.5 inch from the base of the
projectile.
[Illustration: CARTRIDGE CASE AND GRAINS OF POWDER, U.S.N.]
The uniform windage for all calibres is .04 inch; thus, taking the
6-inch gun as an example, the diameter of the bore across the lands
is 6 inches, the diameter of the shell is 5.96 inches, the depth of
the grooves is .05 inch; thus the diameter of the bore across the
grooves is 6.10 inches. In order to permit the rotating ring to fill
the grooves, it must have a diameter of 6.14 inches; this causes a
_squeeze_ of .05 inch between the lands and the rotating ring.
There is no subject in the development of the new naval artillery
more important than the powder. That used with the old artillery is
entirely unsuited to the new conditions that obtain in the modern
high-power guns. A brown powder, introduced first in Germany, has
exhibited decided advantages over all others, and the efforts to
reproduce it have been thoroughly successful at the Du Pont Mills.
It is generally known as “cocoa” powder. Its peculiarity exists in
the method of preparing the charcoal; this affects the color, and
results in a brown instead of a black powder. With this powder,
experiments with the 6-inch gun give a muzzle velocity of over 2000
feet per second with a projectile of 100 pounds, using charges of 50
pounds, and this result is obtained with less than 15 tons pressure
per square inch in the powder chamber. The grain is prismatic, with
a central perforation, and as regards its rate of burning, is under
complete control in the manufacture; the form provides an increasing
surface for the flame during the period of combustion, thus
relieving the gun from abnormal pressures at the moment of ignition,
but continuing the extreme pressure farther along the bore. The
progressive nature of the combustion is very apparent when comparing
an unburned grain with others partially consumed, blown out from the
gun.
[Illustration: COMMON SHELLS, U.S.N.]
The gun-carriage, which is a separate study in itself, is carried to
a high pitch of perfection, and presents many features being adopted
abroad. The importance of a suitable carriage can be appreciated by
inspecting the following table, which exhibits the _energy_ that must
be controlled by it:
Part 1 of 2
+------------------------------------+---------+-----------+---------+
| | | | |
| | Weight | Weight | Muzzle |
| GUN. | of | of |Velocity.|
| | Charge. |Projectile.| |
+------------------------------------+---------+-----------+---------+
| | Pounds. | Pounds. | Feet. |
| 5-inch steel breech-loading rifle | 30 | 60 | 1915 |
| 6-inch steel breech-loading rifle | 50 | 100 | 1915 |
| 8-inch steel breech-loading-rifle | 125 | 250 | 2050 |
| 10-inch steel breech-loading rifle | 250 | 500 | 2100 |
| 12-inch steel breech-loading rifle | 425 | 850 | 2100 |
| 14-inch steel breech-loading rifle | 675 | 1350 | 2100 |
| 16-inch steel breech-loading rifle | 1000 | 2000 | 2100 |
+------------------------------------+---------+-----------+---------+
Part 2 of 2
+---------+----------+-------------+----------+----------+-----------+
| | | Penetration | Muzzle | | |
| | Muzzle | in | Energy | Weight | Weight of |
| GUN. | Energy. |Wrought-iron.| per Ton | of Gun. | Carriage. |
| | | | of Gun. | | |
+---------+----------+-------------+----------+----------+-----------+
| | Ft.-Tons.| Inches. | Ft.-Tons.| Pounds. | Pounds. |
| 5-inch | 1,525 | 10.7 | 552 | 6,187 | 4,200 |
| 6-inch | 2,542 | 13.2 | 521 | 11,000 | 6,400 |
| 8-inch | 7,285 | 18.2 | 560 | 28,000 | 14,000 |
| 10-inch | 15,285 | 23.7 | 588 | 58,240 | 32,482 |
| 12-inch | 25,985 | 27.6 | 591 | 44 tons | .... |
| 14-inch | 41,270 | 32.2 | 550 | 75 tons | .... |
| 16-inch | 61,114 | 36.8 | 571 | 107 tons | .... |
+---------+----------+-------------+----------+----------+-----------+
This _energy_, total energy, expresses the work that the gun can
perform. It is expressed in foot-tons, and signifies that the energy
developed is sufficient to raise the weight in tons to a height of
one foot. Thus the projectile from the small 5-inch gun, weighing
sixty pounds, fired with a charge of thirty pounds of powder, leaves
the gun with an energy capable of lifting 1525 tons to the height of
one foot! Comparing this with the energy developed by the 100-ton
hammer at the forge of Le Creuzot in France, the energy of which is
1640 foot-tons, we have a most striking illustration of the power of
gunpowder, and the testimony in the table as to the energy developed
per ton of gun more forcibly exhibits the perfection of a manufacture
which, with so little weight of gun, can develop such gigantic power.
[Illustration: UNBURNED AND PARTIALLY CONSUMED GRAINS OF U.S.N.
POWDER]
It is this power, united with a moderate weight of gun, which
will enable our unarmored cruisers to hold their own with vessels
moderately armored. The power of the battery is greater than is
required to contend with unarmored ships, there is a great surplus
of power of offence, and the effort is very properly made to sustain
this at the highest practicable point. The table shows that the
5-inch gun can perforate 10.7 inches of wrought-iron at the muzzle;
but the results given in tables are based on deliberate firing made
on a practice-ground, with the position of the target normal to the
line of fire. Such conditions cannot obtain during an action at
sea, for, besides the modified effect caused by increased distance
of target, it must be borne in mind that the side of an enemy’s
ship will be presented at varying angles, which introduces the
element of deflection, than which no cause is more detrimental to
penetration. Though the table states a fact, the practical effect of
the projectile will be far less than is stated, hence the wisdom of
providing a large surplus of power to compensate for the resistance
to its operation.
[Illustration: SECTION OF U.S.N. 6-INCH BUILT-UP STEEL BREECH-LOADING
RIFLE.]
It will readily be conceded that the artillerist has a very
responsible duty to perform in so designing his gun that the parts
shall lock and interlock to guard against chance of dislocation in
the structure. A study of the illustration of the 6-inch built-up gun
as constructed at the Washington navy-yard will show the system there
adopted.
[Illustration: BROADSIDE CARRIAGE FOR 6-INCH BREECH-LOADING RIFLE.]
In the list of guns each calibre is represented by one gun. We have
not, as of old, several guns of the same calibre differing in weight;
multiplicity of classes will be avoided; but this will apply only
to the main battery, for history is singularly repeating itself at
this time in the restoration of the “murdering pieces” which have
been cited as forming part of naval armaments in the seventeenth
century. The needfulness of machine guns for operating against men on
open decks, for effecting entrance through port-holes, for repelling
attacks in boats, and for resisting the approach of torpedo-boats,
is so widely recognized that no vessel of war is considered properly
equipped without a secondary battery of these “murdering pieces.”
They are mounted on the rail, on platforms projecting from the sides
and in the tops. The types adopted in the United States navy are the
Hotchkiss revolving cannon and rapid-firing single-shot guns, and the
smaller calibre machine guns of Gatling. The heavier pieces, throwing
shells of six pounds weight, are very effective against vessels of
ordinary scantling.
In contemplating the present condition of our new naval armament
we have the consolation of knowing that, so far as concerns the
study of the subject generally and in detail, the designs, and the
initial manufacture, all has been done that could have been done
with the resources available. What has been achieved has been
without the facilities that are provided in modern gun-factories;
but notwithstanding all the drawbacks, it is probably safe to assert
that no guns in the world to-day are superior to those that have
been fabricated at the Washington navy-yard of steel on the new
adopted pattern. The work at this ordnance yard is carried on without
ostentation; there is no flourish of trumpets accompanying its
operations; it is not advertised, and the people do not yet know how
much they owe to the ordnance officers of the navy for the initiation
of this new industry, which enables us to assert our ability to
advance in this manufacture through the incontrovertible proof of
work accomplished. The results are meagre in quantity, and at the
present rate of manufacture it will require many years to equip our
fleet with modern artillery; this should be remedied, as there is now
no doubt as to the success of the productions of this establishment.
The plant should be enlarged on a liberal and well-matured plan, and
the work should be encouraged by generous appropriations.
[Illustration: RAPID-FIRING SINGLE-SHOT HOTCHKISS GUN.]
It may not be generally known that the steel forgings required for
the few 8-inch and the two 10-inch guns now in hand were imported
from abroad, for the reason that they could not be furnished
of domestic manufacture, from the want of casting and forging
facilities in the United States for work of such magnitude. This
was a deficiency in our resources that required prompt attention to
secure us a position of independence in this important matter. The
method of achieving the object was carefully studied out by a mixed
board of army and navy officers, and presented in a document known
as the “Gun Foundery Board Report,” and the subject received the
attention of committees from both Houses of Congress. All of these
reports virtually agreed as to the method, but there was a useless
delay in action; large expenditures of money were required, and
there was hesitancy in assuming the responsibility of recommending
it. The object was of national importance, however, and public
opinion demanded its accomplishment. The officers of the navy have
proved their ability to carry on the work successfully; and if the
opportunity be given they will establish the artillery of the United
States navy in a position of which the country may again be proud.
NOTES.
GUNS.
The United States no longer depend upon foreigners for guns or
armor, inasmuch as the circular issued in August, 1886, by the Navy
Department inviting all domestic steel manufacturers to state the
terms upon which they were willing to produce the steel plates and
forgings required for ships and ordnance, has met with a prompt
response. About 4500 tons were needed for armor, in plates varying
from 20 feet by 8 feet by 12 inches thick, to 11.6 feet by 4.3 feet
by 6 inches thick; and of the 1310 tons of steel forgings, 328 tons
were intended for the 6-inch guns, 70 tons for the 8-inch, and 912
tons for the calibres between 10 and 12 inches, both inclusive. The
rough-bored and turned forgings required by the contract were to
weigh 3¼ tons for the 6-inch calibres, 5 tons for the 8-inch, 9½
tons for the 10-inch, 9¾ tons for the 10½-inch, and 12½ tons for
the 12-inch. From the time of closing the contract twenty-eight
6-inch forgings were to be delivered in one year, and the remainder
within eighteen months. All the 8-inch were to be ready within two
years, and the 10-inch and larger calibres within two years and a
half. The proposals opened on the 22d of last March showed that for
the gun-forgings the Cambria Iron Company had bid $851,513, the
Midvale Steel Company $1,397,240, and the Bethlehem Iron Company
$902,230; and that for the armor-plates the Bethlehem Company had
bid $3,610,707, and the Cleveland Rolling-mill Company $4,021,561.
Subsequently the Navy Department awarded the contract to the
Bethlehem Company, which agreed to furnish all the required steel at
a total cost of $4,512,938.29.
The tests are so rigorous that a high quality of steel is sure
to be produced. The specifications require the forgings to be of
open-hearth steel of domestic manufacture, from the best quality of
raw material, uniform in quality throughout the mass of each forging
and throughout the whole order for forgings of the same calibre,
and free from slag, seams, cracks, cavities, flaws, blow-holes,
unsoundness, foreign substances, and all other defects affecting
their resistance and value. While it is prescribed that the ingots
shall be cast solid, latitude is given to the method of production;
but no matter what method may be employed, the part to be delivered
for test and acceptance must be equal in quality and in all other
respects to a gun ingot cast solid in the usual way, from which at
least 30 per cent. of the weight of the ingot has been discarded from
the upper end and 5 per cent. from the lower end.
For breech-pieces each ingot must be reduced in diameter by forging
at least 40 per cent.; in case tubes are forged upon a mandrel from
bored ingots, the walls must be reduced in thickness by forging at
least 50 per cent. Forgings are to be annealed, oil tempered under
such conditions as will assure their resistance and again annealed,
and no piece will be accepted unless the last process has been an
annealing one. The forging must be left with a uniformly fine grain.
All these excellent results are the direct outcomes of the report
made in 1884 by the Ordnance Board. 1st. That the army and navy
should each have its own gun-factory; 2d. That the parts should be
shipped by the steel-makers ready for finishing and assembling in
guns; 3d. That the government should not undertake the production of
steel of its own accord; 4th. That the Watervliet Arsenal, West Troy,
N. Y., should be the site of the army gun-factory; and 5th. That the
Washington navy-yard should be the site of the navy gun-factory. No
action was taken upon the recommendation to establish gun-factories;
but at the first session of the Forty-ninth Congress an appropriation
of $1,000,000 was made for the armament of the navy, of which sum so
much as the Secretary determined might be employed for the creation
of a plant. Under this permission the gun-factory at the Washington
navy-yard is now being established.
The construction of the breech-loading steel guns for the new
cruisers has been energetically pushed. Slight modifications in
the original designs were made necessary by the adoption of slower
burning powder, which carried the pressure still farther forward
in the bore, and, in the case of some foreign guns, caused their
destruction. Though our guns have not suffered from any such
accident, it has been deemed a wise precaution to give the 8-inch
guns of the _Atlanta_ two additional chase hoops, and to hoop all
other pieces of this calibre to the muzzle.
From a memorandum kindly furnished by Lieutenant Bradbury, United
States navy, it is learned that the number and calibre of the new
guns now finished, under construction, or projected, are as follows:
+------------------------+--------------------------------------------+
| NAME OF SHIP. | Calibre. |
+------------------------+--------+--------+--------+--------+--------+
| | 5-inch.| 6-inch.| 8-inch.|10-inch.|12-inch.|
| Dolphin | None. | 1 | None. | None. | None. |
| Atlanta[53] | ” | 6 | 2 | ” | ” |
| Boston[53] | ” | 6 | 2 | ” | ” |
| Chicago[54] | 2 | 8 | 4 | ” | ” |
| Gun-boat No. 1[54] | None. | 6 | None. | ” | ” |
| Gun-boat No. 2 | ” | 4 | ” | ” | ” |
| Newark | ” | 12 | ” | ” | ” |
| Baltimore | ” | 6 | 2 | ” | ” |
| Charleston | ” | 6 | None. | 2 | ” |
| Miantonomoh | ” | None. | ” | 4 | ” |
| Terror | ” | ” | ” | 4 | ” |
| Amphitrite | ” | ” | ” | 4 | ” |
| Monadnock | ” | ” | ” | 4 | ” |
| Puritan | ” | ” | ” | 4 | ” |
| Armored cruiser | ” | 6 | ” | 4 | ” |
| Armored battle-ship[55]| ” | 6 | ” | None. | 2 |
| 2 Gun-boats | ” | 12 | ” | ” | None. |
| 2 Cruisers | ” | 24[56]| ” | ” | ” |
| Floating batteries | ” | None. | ” | ” | 8[56]|
+------------------------+--------+--------+--------+--------+--------+
This gives a total of two 5-inch, one hundred and three 6-inch, ten
8-inch, twenty-six 10-inch, and ten 12-inch. In his last report,
Captain Sicard, Chief of Ordnance, states that “for the new ships
approaching completion we have eighteen 6-inch, three 8-inch, and two
5-inch guns finished, and three 6-inch and five 8-inch well advanced,
together with all the carriages for the _Atlanta_ and _Boston_, and
all for the _Chicago_, except the 8-inch.... With brown powder the
following are the best results obtained in the 6-inch and 8-inch guns.
+-----------+--------------------+---------------+-----------+
| GUN. | Powder. | Muzzle | Pressure. |
| | | Velocity. | |
+-----------+--------------------+---------------+-----------+
| | | Foot seconds. | Tons. |
| 6-inch | American Brown. | 2,105 | 15.6 |
| 8-inch | Westphalian Brown. | 2,013 | 15.5 |
+-----------+--------------------+---------------+-----------+
“It will be observed,” he adds, “that the muzzle velocities are as
high, while the chamber pressures are considerably below those which
the guns were calculated to support in service.”
During the preliminary trials afloat of the _Atlanta’s_ battery in
July, a few minor faults were unfairly given an importance by the
newspapers which led the country to believe that the ship and her
armament were useless. Unfriendly critics vented their spite and
aired their ignorance in condemnations which included all who had
had anything to do, even in the remotest degree, with the design
and construction of vessel and gun. Indeed, so bitter and persistent
were they that for a time it seemed almost hopeless to expect any
further good could come out of the Nazareth of public opinion. It was
not a question of politics, for the journalists of every political
faith ran amuck riotously upon the subject; nor was it a matter
of morals, where, through intelligent discussion, better things
could be attained, for with brilliant misinformation and dogmatic
dulness each scribe stuck his pin-feathered goose-quill into the
navy’s midriff—it being such an easy, such a safe thing to do—and
then thanked Heaven he was a virtuous citizen. Finally, a board was
appointed to inspect the ship and battery, and after a thorough
examination it made the following report:
“In obedience to the Department’s order of the 22d instant, the Board
convened on board the _Atlanta_, Newport, Rhode Island, on the 25th
instant (July, 1887), and made a careful examination of the ship,
guns, carriages, and fittings, and of the damage sustained during the
recent target practice, as reported by the board of officers ordered
by the commanding officer of the _Atlanta_. The Board proceeded to
sea on the morning of the 25th instant, but were prevented from
firing the guns by a heavy fog which prevailed throughout the day.
The ship was again taken to sea on the morning of the 27th instant,
and the guns were fired. No deficiencies were noted in the guns
themselves other than a slight sticking of the breech-plug in 6-inch
breech-loading rifle No. 5 (this disappeared during the firing), some
difficulty in the management of the lock of 6-inch breech-loading
rifle No. 4, caused by slight upsetting of the firing-pin, and the
bending of the extractor in 6-pounder rapid-fire No. 5.
“The recoil and counter-recoil of the 8 and 6 inch guns were easy and
satisfactory, except at the second fire of the 8-inch breech-loading
rifle No. 1, when the gun remained in. (This was readily run out with
a tackle.) The action of the carriage of 8-inch breech-loading rifle
No. 1 at the first fire was due to want of strength in the clips and
clip circles, and at the second fire to want of sufficient bearing
and securing of the deck socket. It is believed that had the deck
socket held, the carriage would not have been disabled by the giving
way of the clips. The training gear, steam and hand, was uninjured;
the gun was readily trained when run out to place. The action of the
after 6-inch shifting gun No. 4 was satisfactory, notwithstanding
that the front clips had a play of half an inch. The action of the
broadside carriages of 6-inch guns Nos. 5 and 18 was satisfactory,
except the breaking of clips, the starting of the copper rivets in
the clip circles, and the wood screws in the training circles.
“It is believed from the action of the carriage of 6-inch
breech-loading rifle No. 5, when the clips were removed, that the
carriages can be safety used without clips. The clips, however, give
additional security and steadiness to the carriage, and assist the
pivot and socket in bearing the shock of the discharge. The firing of
the 6-pounder rapid-fire guns developed a weakness in one leg of the
cage mount of No. 4, due to imperfect workmanship, and showed also
the necessity of locking nuts on the bolts that secure the mounts
to the ports. The tower mounts of the 3-pounder rapid-fire guns are
unsatisfactory. They cannot be moved with facility; the line of
sight of the gun is obstructed at ranges beyond 1600 yards, and the
guns cannot be safely used as now fitted. For this reason 3-pounder
rapid-fire No. 3 was not fired. The tripod mounts of the 1-pounder
rapid-fire guns need stronger holding-down arrangements. The tower
mounts of the 47-millimetre revolving cannon are like those of the
3-pounder rapid-fire guns, and have the same defects. The mounts of
the 37-millimetre in the tops are satisfactory.
“Careful observation of the effect of the firing upon the hull of the
vessel failed to develop any damage other than the breaking of the
cast-steel port-sills and the starting of some light wood-work. The
shock of discharge was slight on the berth-deck, and observers there
were unable to observe which 6-inch gun had been fired. The deck,
hull, and fittings, with the exception of the port-sills, hinges to
superstructure doors and vegetable lockers, and some of the light
wood-work, have every appearance of strength and ability to endure
the strain of continuous firing of the guns. The blast of the forward
8-inch gun, when fired abaft the starboard beam, will not permit the
crews of the starboard 3-pounder rapid fire and 1-pounder rapid fire
to remain at their guns. When the after 8-inch gun is fired forward
of the port beam, the crews of the after 47-millimetre revolving
cannon and of the port after 1-pounder rapid fire cannot remain at
their guns. When the forward 6-inch shifting gun is fired on the port
bow or directly ahead, the crew of forward 8-inch gun cannot remain
at their places. When the after 6-inch shifting gun is fired on the
starboard quarter or directly aft, the crew of the after 8-inch
gun cannot remain at their gun. The inability to fire parts of the
secondary battery under certain conditions is due to the great arc of
fire given to the 8-inch guns. This can hardly be called a defect. It
is thought that a screen can be placed between the 8 and 6 inch guns
which will enable them to be worked together forward or aft.
“The pivot socket of the 8-inch carriage should have a broader
bearing surface, and should be rigidly bolted to the steel deck and
to the framework of the ship in such manner as to distribute the
strain over a larger area. The clips and clip circles of the 8-inch
and 6-inch carriage should be made of steel. The clips should have
larger bearing surfaces, and should be shaped to fit the circle. The
circle should have double flanges, and be bolted (not riveted) on
each flange to the steel deck. There should be no appreciable play
between the clips and the circles. All bolts used in the battery
fittings should have the nuts locked.
“The clip rail of the tower mount should be altered to fit the mount.
This change will make the compressors effective, and allow the guns
to be used with safety. The port-sills should be replaced by heavier
sills, made of the best quality of malleable cast-steel. The plan of
testing the hull, guns, and fittings of the _Atlanta_ arranged by the
Board contemplated a more extended use of the main battery, but the
weakness developed in the port-sills and in the sockets of the 8-inch
carriages rendered further firing inadvisable.”
Whatever conclusion may be drawn from this report, there is one fact
which may serve as an important corollary. In the latest drills
of the ships on the North Atlantic station, the _Atlanta_ won the
champion pennant for the best gunnery practice, and this with guns
and carriages which were said to be completely disabled.