The contemporary descriptions of the Fulton _Steam Battery_ do not
agree. This was in part due to differences between the dimensions given
out by Fulton during the negotiations with the Federal Government, and
after the ship's construction was authorized. From the context of
various statements concerning the projected vessel, such as that of the
naval officers, the changes in the intended dimensions of the ship can
be seen. For example, the officers state the model and plan shown them
would produce a battery carrying 24 guns (24- and 32-pdrs.), and a letter
from Fulton to Jones,[9] shows she was to be 138 feet on deck and
55-foot beam. The final reported dimensions, given by the Supervisory
Committee,[10] are 156 feet length, 56 feet beam, and 20 feet depth.
In addition there are a few foreign accounts which give dimensions and
descriptions. The most complete was probably that of Jean Baptiste
Marestier, a French naval constructor who visited the United States soon
after the end of the War of 1812 and published a report on American
steamboats in 1824.[11] The _Steam Battery_ is barely mentioned though a
drawing of one of her boilers is given. Marestier made another report on
the American Navy, however. Extensive searches have been made for this
in Paris over the last 14 years, but this paper has not been found in
any of the French archives. References to the original text indicate
that the naval report dealt very extensively with the _Steam Battery_.
Some of his comments on the battery appeared in _Procès-verbaux des
Séances de l'Académie des Sciences_.[12] Marestier considered the powers
of the battery to have been overrated due to fanciful accounts of some
laymen writers. He was aware of the shortcomings of the double hull in a
steam vessel at the then-possible speeds, but he apparently thought two
engines, one in each hull and each with its boilers would be better than
Fulton's arrangement of boilers in one hull and engine in the other. He
noted that the paddle wheel turned 16-18 rpm and that steam pressure
sustained a column of mercury 25 to 35 centimeters. The safety valve was
set at 50 centimeters. Fuel consumption was 3-5/8 cords of pine wood per
hour.
In view of the access Marestier is known to have had to American naval
constructors, shipbuilders, and engineers, it is highly probable that he
not only obtained the building plan of the ship but also some of the
earlier project plans from the builders and from Fulton's
superintendent, Stoudinger. It is, therefore, a great misfortune that
his lengthy report on the _Battery_ cannot be produced.
A French naval officer who investigated the ship, M. Montgéry, also
wrote a description, published in "Notice sur la Vie et les Travaux de
Robert Fulton."[13]
[Illustration: Figure 5.--FLOATING BATTERY _Spanker_ built, in England
by William Barnard, at Deptford on the Thames, and launched June 14,
1794. Rigged as a bomb ketch, its length is 111 feet 7 inches in the
keel, extreme beam 42 feet 4 inches, depth of hold 8 feet. Upper deck
plan also shown.]
It should be noted in regard to what Montgéry wrote about the
_Battery_, that in 1821 it had been considered desirable to disarm the
ship. The engineer in charge, William Purcell, had reported that as
there were not proper scuppers, dirt and water had entered the hull and
had collected under the engine and boilers, causing damage to the hull,
and also that with guns removed, the _Battery_ would float too high for
the paddle wheel to propel the vessel; so it had been decided to remove
all machinery as well as the armament.
Montgéry's description, published in 1822, was taken from his report to
the Minister of Marine and Colonies. It noted the battery was made of
two hulls separated by a channel, or "race," 15-1/2 feet wide, running
the full length of the vessel. The two hulls were joined by a deck just
above the waterline, as well as by an upper deck, and also connected at
their keels by means of 12 oak beams each 1 foot square. The vessel was
152 feet long, 57 feet beam, and 20 feet deep. Sides were 4 feet 10
inches thick, and the ends of the hull were rounded and alike. There
were two rudders at each end, one on each hull, alongside the race. The
eight paddle blades, each 14-1/2 feet by 3 feet, turned in either
direction by stopping the engine piston at half-stroke and reversing the
flow of steam. Rigged with two lateen sails and two jibs, the ship
sailed either end first. The engine of 120 hp was in one hull and two
boilers were in the other. Other sources, Marestier, and Colden in
_Procès-verbaux des Séances de l'Académie des Sciences_,[14] gave
additional information (some of it incorrect): the engine was inclined,
with a 4-foot-diameter cylinder, 5-foot stroke, direct-connected to the
paddle wheel, which was turned at 18 rpm. The boilers were 8 × 22 feet
with the fireboxes in inside cylinders, each about 5 feet in diameter,
and extending about half the length of the boiler from the fire doors.
Two fire tubes, each about 3 feet in diameter, returned the gases from
the inside end of the fireboxes to the stacks at the firing end. Except
at the fire-door end, the firebox was completely surrounded by water.
The boiler pressure of about 6 psi was not maintained, varying somewhat
with each stroke of the engine.
Water level in the boilers was indicated by try cocks. The safety valve
was controlled by a counterbalanced lever. A jet of salt water was
injected into the exhaust trunk to form a vacuum by condensation. An air
pump transferred condensate and sea water into a tank from which it
passed overboard. Only about a tenth of this water was returned to the
boilers.
Montgéry stated also that only the lower or gun deck was to be armed. No
bulwarks were on the spar deck, only iron stanchions to which were
fastened a breastwork of wet cotton bales when the _Steam Battery_ was
in action.
The _Battery_ was designed to carry 30 guns (32-pdr.), with 3 guns in
each end and 12 on each side, but no guns in the wake of paddle wheel
and machinery. Hatches to give air to the stokehold were located
amidships. The _Battery_ was to have been supplemented at the ends of
each hull by a Columbiad "submarine gun" (100-pdr.), Fulton's invention,
but these were not fitted. Provision was to be made in the fireboxes for
heating shot, and a force pump with a cylinder 33 inches in diameter was
employed to throw a stream of cold water, about 60-80 gallons per
minute, for a distance of about two hundred feet. This could be done
only when the paddle wheel was not in operation. The paddle wheel was
housed, the top fitted with stairs to the spar deck. The gun deck, over
the race, was used in part for staterooms, of which the bulkheads were
permanent. Hammocks for the complement of 500 men were to be slung on
the rest of the gun deck. The ship drew 10 feet 4 inches, with the port
sills about 5-1/2 feet above the loadline. Burning wood, the vessel
could carry about 4 days' supply of fuel; burning coal, she carried 12
days' supply.
Montgéry said that the vessel would be vulnerable to bombshells and hot
shot, and that furthermore she could be boarded. The displacement of the
ship, at service draft, was 1,450 tons, a figure Montgéry obtained from
a copy of the original plan given him by Noah Brown.
[Illustration: Figure 6.--FRENCH SKETCH, in Rigsarkivet, Copenhagen, of
inboard profile and arrangement of Fulton's _Steam Battery_, showing
details of the Fulton engine, probably taken from one of his preliminary
designs.]
In 1935, Lieutenant Ralph R. Gurley, USN, attempted a reconstruction in
sketches of the vessel published in his article "The U.S.S. _Fulton_ the
First" in the _U.S. Naval Institute Proceedings_.[15] This
reconstruction was based on the Patent Office drawing prepared for
Fulton, and published by Stuart and Bennett, and the foregoing French
sources. The Patent Office drawing showed the engine was an inclined
cylinder and Lt. Gurley shows this in his sketch; in his text (p. 323)
he says, "The engine was an inclined, single-cylinder affair with a
4-foot base and a 5-foot stroke." Gurley's attempt to reconstruct the
_Steam Battery_ is the only one known to the author.