the summer of 1808 was again on the route to Albany; and, meantime,
two new steamboats--the Raritan and the Car of Neptune--had been built
by Fulton. In the year 1811 he built the Paragon. Both of the two
vessels last named were of nearly double the size of the Clermont. A
steam ferry-boat was built to ply between New York and Jersey City in
1812, and the next year two others, to connect the metropolis with
Brooklyn. These were "twin-boats," the two parallel hulls being
connected by a "bridge" or deck common to both. The Jersey ferry was
crossed in fifteen minutes, the distance being a mile and a half.
To-day, the time occupied at the same ferry is about ten minutes.
Fulton's ferry-boat carried, at one load, 8 carriages, and about 30
horses, and still had room for 300 or 400 foot-passengers. Fulton also
designed steam-vessels for use on the Western rivers, and, in 1815,
some of his boats were started as "packets" on the line between New
York and Providence, R. I.
Meantime, the War of 1812 was in progress, and Fulton designed a steam
vessel-of-war, which was then considered a wonderfully formidable
craft. His plans were submitted to a commission of experienced naval
officers, among whom were Commodores Decatur and Perry, Captain John
Paul Jones, Captain Evans, and others whose names are still familiar,
and were favorably commended. Fulton proposed to build a steam-vessel
capable of carrying a heavy battery, and of steaming four miles an
hour. The ship was to be fitted with furnaces for red-hot shot. Some
of her guns were to be discharged below the water-line. The estimated
cost was $320,000.
The construction of the vessel was authorized by Congress in March,
1814; the keel was laid June 20, 1814, and the vessel was launched
October 29th of the same year.
[Illustration: FIG. 82.--Launch of the "Fulton the First," 1804.]
The "Fulton the First," as she was called, was considered an enormous
vessel at that time. The hull was double, 156 feet long, 56 feet wide,
and 20 feet deep, measuring 2,475 tons. In the following May the ship
was ready for her engine, and in July was so far completed as to
steam, on a trial-trip, to the ocean at Sandy Hook and back--53
miles--in 8 hours and 20 minutes. In September of the same year, with
armament and stores on board, the same route was traversed again, the
vessel making 5-1/2 miles an hour. The vessel, as thus completed, had
a double hull, each about 20 feet longer than the Clermont, and
separated by a space 15 feet across. Her engine, having a
steam-cylinder 48 inches in diameter and of 5 feet stroke of piston,
was furnished with steam by a copper boiler 22 feet long, 12 feet
wide, and 8 feet high, and turned a wheel between the two hulls which
was 16 feet in diameter, and carried "floats" or "buckets" 14 feet
long, and with a dip of 4 feet. The engine was in one of the two
hulls, and the boiler in the other. The sides, at the gun-deck, were 4
feet 10 inches thick, and her spar-deck was surrounded by heavy
musket-proof bulwarks. The armament consisted of 30 32-pounders, which
were intended to discharge red-hot shot. There was one heavy mast for
each hull, fitted with large latteen sails. Each end of each hull was
fitted with a rudder. Large pumps were carried, which were intended to
throw heavy streams of water upon the decks of the enemy, with a view
to disabling the foe by wetting his ordnance and ammunition. A
submarine gun was to have been carried at each bow, to discharge shot
weighing 100 pounds, at a depth of 10 feet below the water-line.
This was the first application of the steam-engine to naval purposes,
and, for the time, it was an exceedingly creditable one. Fulton,
however, did not live to see the ship completed. He was engaged in a
contest with Livingston, who was then endeavoring to obtain permission
from the State of New Jersey to operate a line of steamboats in the
waters of the Hudson River and New York Bay, and, while returning from
attending a session of the Legislature at Trenton, in January, 1815,
was exposed to the weather on the bay at a time when he was ill
prepared to withstand it. He was taken ill, and died February 24th of
that year. His death was mourned as a national calamity.
From the above brief sketch of this distinguished man and his work, it
is seen that, although Robert Fulton is not entitled to distinction as
an inventor, he was one of the ablest, most persistent, and most
successful of those who have done so much for the world by the
introduction of the inventions of others. He was an intelligent
engineer and an enterprising business-man, whose skill, acuteness, and
energy have given the world the fruits of the inventive genius of all
who preceded him, and have thus justly earned for him a fame that can
never be lost.
Fulton had some active and enterprising rivals.
Oliver Evans had, in 1801 or 1802, sent one of his engines, of about
150 horse-power, to New Orleans, for the purpose of using it to propel
a vessel owned by Messrs. McKeever and Valcourt, which was there
awaiting it. The engine was actually set up in the boat, but at a low
stage of the river, and no trial could be made until the river should
again rise, some months later. Having no funds to carry them through
so long a period, Evans's agents were induced to remove the engine
again, and to set it up in a saw-mill, where it created great
astonishment by its extraordinary performance in sawing lumber.
Livingston and Roosevelt were also engaged in experiments quite as
early as Fulton, and perhaps earlier.
The prize gained by Fulton was, however, most closely contested by
Colonel JOHN STEVENS, of Hoboken, who has been already mentioned in
connection with the early history of railroads, and who had been since
1791 engaged in similar experiments. In 1789 he had petitioned the
Legislature of the State of New York for a grant similar to that
accorded to Livingston, and he then stated that his plans were
complete, and on paper.
[Illustration: FIG. 83.--Section of Steam-Boiler, 1804.]
In 1804, while Fulton was in Europe, Stevens had completed a
steamboat, 68 feet long and of 14 feet beam, which combined novelties
and merits of design in a manner that exhibited the best possible
evidence of remarkable inventive talent, as well as of the most
perfect appreciation of the nature of the problem which he had
proposed to himself to solve. Its boiler (Fig. 83) was of what is now
known as the water-tubular variety. It was quite similar to some now
known as sectional boilers, and contained 100 tubes 2 inches in
diameter and 18 inches long, each fastened at one end to a central
water-leg and steam-drum, and plugged at the other end. The flames
from the furnace passed around and among the tubes, the water being
inside them. The engine (Fig. 84) was a _direct-acting high-pressure_
condensing engine, having a 10-inch cylinder, 2 feet stroke of piston,
and drove a _screw_ having four blades, and of a form which, even
to-day, appears quite good. The whole is a most remarkable piece of
early engineering.
[Illustration: FIG. 84.--Engine, Boiler, and Screw-Propellers used by
Stevens, 1804.]
A model of this little steamer, built in 1804, is preserved in the
lecture-room of the Department of Mechanical Engineering at the
Stevens Institute of Technology; and the machinery itself, consisting
of the high-pressure "sectional" or "safety" tubular boiler, as it
would be called to-day, the high-pressure condensing engine, with
rotating valves, and twin screw-propellers, as just described, is
given a place of honor in the model-room, or museum, where it
contrasts singularly with the mechanism contributed to the collection
by manufacturers and inventors of our own time. The hub and blade of a
single screw, also used with the same machinery, is likewise to be
seen there.
[Illustration: FIG. 85.--Stevens's Screw Steamer, 1804.]
Stevens seems to have been the first to fully recognize the importance
of the principle involved in the construction of the sectional
steam-boiler. His eldest son, John Cox Stevens, was in Great Britain
in the year 1805, and, while there, patented another modification of
this type of boiler. In his specification, he details both the method
of construction and the principles which determine its form. He says
that he describes this invention as it was made known to him by his
father, and adds:
"From a series of experiments made in France, in 1790, by M. Belamour,
under the auspices of the Royal Academy of Sciences, it has been found
that, within a certain range the elasticity of steam is nearly doubled
by every addition of temperature equal to 30 deg. of Fahrenheit's
thermometer. These experiments were carried no higher than 280 deg., at
which temperature the elasticity of steam was found equal to about
four times the pressure of the atmosphere. By experiments which have
lately been made by myself, the elasticity of steam at the temperature
of boiling oil, which has been estimated at about 600 deg., was found to
equal 40 times the pressure of the atmosphere.
"To the discovery of this principle or law, which obtains when water
assumes a state of vapor, I certainly can lay no claim; but to the
application of it, upon certain principles, to the improvement of the
steam-engine, I do claim exclusive right.
"It is obvious that, to derive advantage from an application of this
principle, it is absolutely necessary that the vessel or vessels for
generating steam should have strength sufficient to withstand the
great pressure from an increase of elasticity in the steam; but this
pressure is increased or diminished in proportion to the capacity of
the containing vessel. The principle, then, of this invention consists
in forming a boiler by means of a system, or combination of a number
of small vessels, instead of using, as in the usual mode, one large
one; the relative strength of the materials of which these vessels
are composed increasing in proportion to the diminution of capacity.
It will readily occur that there are an infinite variety of possible
modes of effecting such combinations; but, from the nature of the
case, there are certain limits beyond which it becomes impracticable
to carry on improvement. In the boiler I am about to describe, I
apprehend that the improvement is carried to the utmost extent of
which the principle is capable. Suppose a plate of brass of one foot
square, in which a number of holes are perforated; into each of which
holes is fixed one end of a copper tube, of about an inch in diameter
and two feet long; and the other ends of these tubes inserted in like
manner into a similar piece of brass; the tubes, to insure their
tightness, to be cast in the plates; these plates are to be inclosed
at each end of the pipes by a strong cap of cast-iron or brass, so as
to leave a space of an inch or two between the plates or ends of the
pipes and the cast-iron cap at each end; the caps at each end are to
be fastened by screw-bolts passing through them into the plates; the
necessary supply of water is to be injected by means of a forcing-pump
into the cap at one end, and through a tube inserted into the cap at
the other end the steam is to be conveyed to the cylinder of the
steam-engine; the whole is then to be encircled in brickwork or
masonry in the usual manner, placed either horizontally or
perpendicularly, at option.
"I conceive that the boiler above described embraces the most eligible
mode of applying the principle before mentioned, and that it is
unnecessary to give descriptions of the variations in form and
construction that may be adopted, especially as these forms may be
diversified in many different modes."
Boilers of the character of those described in the specification given
above were used on the locomotive built by John Stevens in 1824-'25,
and one of them remains in the collections of the Stevens Institute of
Technology.
The use of such a boiler 70 years ago is even more remarkable than the
adoption of the screw-propeller, in such excellent proportions, 30
years before the labors of Smith and of Ericsson brought the screw
into general use; and we have, in this strikingly original
combination, as good evidence of the existence of unusual engineering
talent in this great engineer as we found of his political and
statesmanlike ability in his efforts to forward the introduction of
railways.
Colonel John Stevens designed a peculiar form of iron-clad in the year
1812, which has been since reproduced by no less distinguished and
successful an engineer than the late John Elder, of Glasgow, Scotland.
It consisted of a saucer-shaped hull, carrying a heavy battery, and
plated with iron of ample thickness to resist the shot fired from the
heaviest ordnance then known. This vessel was secured to a swivel, and
was anchored in the channel to be defended. A set of screw-propellers,
driven by steam-engines, and situated beneath the vessel, where they
were safe against injury by shot, were so arranged as to permit the
vessel to be rapidly revolved about its centre. As each gun was
brought into line of fire, it was discharged, and was then reloaded
before coming around again. This was probably the earliest embodiment
of the now well-established "Monitor" principle. It was probably the
first iron-clad ever designed. It has recently been again brought out
and introduced into the Russian navy, and is there called the
"Popoffka."
The first of Stevens's boats performed so well, that he immediately
built another one, using the same engine as before, but employing a
larger boiler, and propelling the vessel by _twin screws_, the latter
being another instance of his use of a device brought forward long
afterward as new, and frequently adopted. This boat was sufficiently
successful to prove the practicability of making steam-navigation a
commercial success; and Stevens, assisted by his sons, built a boat
which he named the "Ph[oe]nix," and made the first trial in 1807, but
just too late to anticipate Fulton. This boat was driven by
paddle-wheels.
[Illustration: FIG. 86.--Stevens's Twin-Screw Steamer, 1805.]
The Ph[oe]nix, being shut out of the waters of the State of New York
by the monopoly held by Fulton and Livingston, was used for a time
between New York and New Brunswick, and then, anticipating a better
pecuniary return, it was concluded to send her to Philadelphia, to ply
on the Delaware.
At that time no canal offered the opportunity to make an inland
passage; and in June, 1808, Robert L. Stevens, a son of John, started
with her to make the passage by sea. Although meeting a gale of wind,
he arrived at Philadelphia safely, having been the first to trust
himself on the open sea in a vessel relying entirely upon steam-power.
From this time forward the Stevenses, father and sons, continued to
construct steam-vessels; and, after the breaking down of the Fulton
monopoly by the courts, they built the most successful steamboats that
ran on the Hudson River.
After Fulton and Stevens had thus led the way, steam-navigation was
introduced very rapidly on both sides of the ocean; and on the
Mississippi the number of boats set afloat was soon large enough to
fulfill Evans's prediction that the navigation of that river would
ultimately be effected by steam-vessels.
The changes and improvements which, during the 20 years succeeding the
time of Fulton and of John Stevens, gradually led to the adoption of
the now recognized type of "American river-boat" and its steam-engine,
were principally made by that son of the senior Stevens, who has
already been mentioned--ROBERT L. STEVENS--and who became known later
as the designer and builder of the first well-planned iron-clad ever
constructed, the Stevens Battery. Much of his best work was done
during his father's lifetime.
[Illustration: Robert L. Stevens.]
He made many extended and most valuable, as well as interesting,
experiments on ship-propulsion, expending much time and large sums of
money upon them; and many years before they became generally
understood, he had arrived at a knowledge not only of the laws
governing the variation of resistance at excessive speeds, but he had
determined, and had introduced into his practice, those forms of least
resistance and those graceful water-lines which have only recently
distinguished the practice of other successful naval architects.
Referring to his invaluable services, President King, who seems to
have been the first to thoroughly appreciate the immense amount of
original invention and the surprising excellence of the engineering of
this family, in a lecture delivered in New York in 1851, gave, for the
first time, a connected and probably accurate description of their
work, upon which nearly all later accounts have been based.
Young Stevens began working in his father's machine-shop in 1804 or
1805, when a mere boy, and thus acquired at a very early age that
familiarity with practical details of work and of business which is
essential to perfect success. It was he who introduced the now common
"hollow water-line" in the Ph[oe]nix, and thus anticipated the claims
of the builders of the once famous "Baltimore clippers," and of the
inventors of the "wave-line" form of vessels. In the same vessel he
adopted a feathering paddle-wheel and the guard-beam now universally
seen in our river steamboats.
As usually constructed, this arrangement of float is as shown in Fig.
87. The rods, _F F_, connect the eccentrically-set collar, _G_,
carried on _H_, a pin mounted on the paddle-beam outside the wheel, or
an eccentric secured to the vessel, with the short arms, _D D_, by
which the paddles are turned upon the pins, _E E_. _A_ is the centre
of the paddle-wheel, and _C C_ are arms. Circular hoops, or bands,
connect all of the arms, each of which carries a float. They are all
thus tied together, forming a very firm and powerful combination to
resist external forces.
[Illustration: FIG. 87.--The Feathering Paddle-Wheel.]
The steamboat Philadelphia was built in the year 1813, and the young
naval architect took advantage of the opportunity to introduce several
new devices, including screw-bolts in place of tree-nails, and
diagonal knees of wood and of iron. Two years later he altered the
engines of this boat, and arranged them to work steam expansively. A
little later he commenced using anthracite coal, which had been
discovered in 1791 by Philip Ginter, and introduced at Wilkesbarre,
Pa., in the smith-shops, some years before the Revolution. It had been
used in a peculiar grate devised by Judge Fell, of that town, in 1808.
Oliver Evans also had used it in stoves even earlier than the latter
date, and at about the same time it had been used in the
blast-furnace[81] at Kingston. Stevens was the first of whom we have
record who was thoroughly successful in using, as a steam-coal, the
new and almost unmanageable fuel. He fitted up the boiler of the
steamboat Passaic for it in 1818, and adopted anthracite as a
steaming-coal. He used it in a cupola-furnace in the same year, and
its use then rapidly became general in the Eastern States.
[81] Bishop.
Stevens continued his work of improving the beam-engine for many
years. He designed the now universally-used "skeleton-beam," which is
one of the characteristic features of the American engine, and placed
the first example of this light and elegant, yet strong, construction
on the steamer Hoboken in the year 1822. He built the Trenton, which
was then considered an extraordinarily powerful, fast, and handsome
vessel, two years afterward, and placed the two boilers on the
guards--a custom which is still general on the river steamboats of the
Eastern States. In this vessel he also adopted the plan of making the
paddle-wheel floats in two parts, placing one above the other, and
securing the upper half on the forward and the lower half on the after
side of the arm, thus obtaining a smoother action of the wheel, and
less loss by oblique pressures.
In 1827 he built the North America (Fig. 88), one of his largest and
most successful steamers, a vessel fitted with a pair of engines each
44-1/2 inches in diameter of cylinder and 8 feet stroke of piston,
making 24 revolutions per minute, driving the boat 15 to 16 miles an
hour. Anticipating difficulty in keeping the long, light, shallow
vessel in shape when irregularly laden, and when steaming at the high
speed expected to be obtained when her powerful engine was exerting
its maximum effort, he adopted the expedient of stiffening the hull by
means of a truss of simple form. This proved thoroughly satisfactory,
and the "hog-frame," as it has since been inelegantly but universally
called, is still one of the peculiar features of every American
river-steamer of any considerable size. It was in the North America,
also, that he first introduced the artificial blast for forcing the
fires, which is still another detail of now usual practice.
[Illustration: FIG. 88.--The North America and Albany, 1827-'30.]
Stevens next turned his attention to the engine again, and adopted
spring bearings under the paddle-shaft of the New Philadelphia in
1828, and fitted the steam-cylinder with the "double-poppet" valve,
which is now universally used on beam-engines. This consists of two
disk-valves, connected by the valve-spindle. The disks are of unequal
sizes, the smaller passing through the seat of the larger. When
seated, the pressure of the steam is, in the steam-valve, taken on the
upper side of the larger and the lower side of the smaller disk, thus
producing a partial balancing of the valve, and rendering it easy to
work the heaviest engine by the hand-gear. The two valve-seats are
formed in the top and the bottom, respectively, of the steam-passage
leading to the cylinder; and when the valve is raised, the steam
enters at the top and the bottom at the same time, and the two
currents, uniting, flow together into the steam-cylinder. The same
form of valve is used as an exhaust-valve.
At about the same time he built the now standard form of return
tubular boilers for moderate pressures. In the figure, _S_ is the
steam and _W_ the water space, and _F_ the furnace. The direction of
the currents of smoke and gas are shown by the arrows.
[Illustration: FIG. 89.--Stevens's Return Tubular Boiler, 1832.]
Some years later (1840), Stevens commenced using steam-packed pistons
on the Trenton, in which steam was admitted by self-adjusting valves
behind the metallic packing-rings, setting them out more effectively
than did the steel springs then (and still) usually employed.
His pistons, thus fitted, worked well for many years. A set of the
small brass check-valves used in a piston of this kind, built by
Stevens, and preserved in the cabinets of the Stevens Institute of
Technology, are good evidence of the ingenuity and excellent
workmanship which distinguished the machinery constructed under the
direction of this great engineer.
[Illustration: FIG. 90.--Stevens's Valve-Motion.]
The now familiar "Stevens cut-off," a peculiar device for securing the
expansion of steam in the steam-cylinder, was the invention (1841) of
Robert L. Stevens and a nephew, who inherited the same constructive
talent which distinguished the first of these great men--Mr. Francis
B. Stevens. In this form of valve-gear, the steam and exhaust valves
are independently worked by separate eccentrics, the latter being set
in the usual manner, opening and closing the exhaust-passages just
before the crank passes its centre. The steam-eccentric is so placed
that the steam-valve is opened as usual, but closed when but about
one-half the stroke has been made. This result is accomplished by
giving the eccentric a greater throw than is required by the motion of
the valve, and permitting it to move through a portion of its path
without moving the valve. Thus, in Fig. 90, if _A B_ be the direction
of motion of the eccentric-rod, the valve would ordinarily open the
steam-port when the eccentric assumes the position _O C_, closing when
the eccentric has passed around to _O D_. With the Stevens valve-gear,
the valve is opened when the eccentric reaches _O E_, and closes when
it arrives at _O F_. The steam-valve of the opposite end of the
cylinder is open while the eccentric is moving from _O M_ to _O K_.
Between _K_ and _E_, and between _F_ and _M_, both valves are seated.
_H B_ is proportional to the lift of the valve, and _O H_ to the
motion of the valve-gear when out of contact with the valve-lifters.
While the crank is moving through an arc, _E F_, steam is entering the
cylinder; from _F_ to _M_ the steam is expanding. At _M_ the stroke is
completed, and the other steam-valve opens. The ratio (E M)/(E L) is
the ratio of expansion.
This form of cut-off motion is still a very usual one, and can be seen
in nearly all steamers in the United States not using the device of
Sickles. It was at about this time, also, that Stevens, having
succeeded his father in the business of introducing the steam-engine
in land-transportation, as well as on the water, adopted the use of
steam expansively on the locomotives of the Camden & Amboy Railroad,
which was controlled and built by capital furnished principally by the
Messrs. Stevens. He at the same time constructed eight-wheeled engines
for heavy work, and adopted anthracite coal as fuel. In the latter
change he was thoroughly successful, and the same improvement was made
with engines built for fast traffic in 1848.
The most remarkable of all the applications of steam-power proposed by
Robert L. Stevens was that known as the Stevens Steam Iron-Clad
Battery. As has already been stated, Colonel John Stevens had
proposed, as early as 1812, to build a circular or saucer-shaped
iron-clad, like those built 60 years later for the Russian Navy.
Nothing was done, however, although the son revived the idea in a
modified form 20 years afterward. In the years 1813-'14, the war with
England being then in progress, he invented, after numerous and
hazardous experiments, an _elongated shell_, to be fired from ordinary
smooth-bored cannon. Having perfected this invention, he sold the
secret to the United States, after making experiments to prove their
destructiveness so decisive as to leave no doubt of the efficacy of
such projectiles.
As early as 1837 he had perfected a plan of an iron-clad war-vessel,
and in August, 1841, his brothers, James C. and Edwin A. Stevens,
representing Robert L., addressed a letter to the Secretary of the
Navy, proposing to build an iron-clad vessel of high speed, with all
its machinery below the water-line, and having submerged
screw-propellers. The armament was to consist of the most powerful
rifled guns, loading at the breech, and provided with elongated shot
and shell. In the year 1842, having contracted to build for the United
States Government a large war-steamer on this plan, which should be
shot and shell proof, Robert L. Stevens built a steamboat at
Bordentown, for the sole purpose of experimenting on the forms and
curves of propeller-blades, as compared with side-wheels, and
continued his experiments for many months. After some delay, during
which Mr. Stevens and his brothers were engaged with their experiments
and in perfecting their plans, the keel of an iron-clad was laid down
in a dry-dock which had been constructed for the purpose at great
cost. This vessel was to have been 250 feet long, of 40 feet beam, and
28 feet deep. The machinery was designed to furnish 700 indicated
horse-power. The plating was proposed to be 4-1/2 inches thick--the
same thickness of armor as was adopted 10 years later by the French
for their comparatively rude constructions.
In 1854, such marked progress had been made in the construction of
ordnance that Mr. Stevens was no longer willing to proceed with the
original plans, fearing that, were the ship completed, it might prove
not invulnerable, and might throw some discredit upon its designer, as
well as upon the navy of which it was to form a part. The work, which
had, in those years of peace, progressed very slowly and
intermittently, was therefore stopped entirely, the vessel given up,
and in 1854 the keel of a ship of vastly greater size and power was
laid down. The new design was 415 feet long, of 45 feet beam, and of
something over 5,000 tons displacement. The thickness of armor
proposed was 6-3/4 inches--2-1/4 inches thicker than that of the
first French and British iron-clads--and the machinery was designed by
Mr. Stevens to be of 8,624 indicated horse-power, driving twin-screws,
and propelling the vessel 20 miles or more an hour. As with the
preceding design, the progress of construction was intermittent and
very slow. Government advanced funds, and then refused to continue the
work; successive administrations alternately encouraged and
discouraged the engineer; and he finally, cutting loose entirely from
all official connections, went on with the work at his own expense.
The remarkable genius of the elder Stevens was well reflected in the
character of his son, and is in no way better exemplified than by the
accuracy with which, in this great ship, those forms and proportions,
both of hull and machinery, were adopted which are now, twenty-five
years later, recognized as most correct under similar conditions. The
lines of the vessel are beautifully fair and fine, and are what J.
Scott Russell has called "wave-lines," or trochoidal lines, such as
Rankine has shown to be the best possible for easy propulsion. The
proportion of length to midship dimensions is such as to secure the
speed proposed with a minimum resistance, and to accord closely with
the proportions arrived at and adopted by common consent in present
transoceanic navigation by the best--not to say radical--builders.
The death of Robert L. Stevens occurred in April, 1856, when this
larger vessel had advanced so far toward completion that the hull and
machinery were practically finished, and it only remained to add the
armor-plating, and to decide upon the form of fighting-house and upon
the number and size of guns. The construction of the vessel, which had
proceeded slowly and intermittently during the years of peace, as
successive administrations had considered it necessary to continue the
payment of appropriations, or had stopped temporarily in the absence
of any apparent immediate necessity for continuance of the work, was
again interrupted by his death.
The name of Robert L. Stevens will be long remembered as that of one
of the greatest of American mechanics, the most intelligent of naval
architects, and as the first, and one of the greatest, of those to
whom we are indebted for the commencement of the mightiest of
revolutions in the methods and implements of modern naval warfare.
American mechanical genius and engineering skill have rarely been too
promptly recognized, and no excuse will be required for an attempt
(which it is hoped may yet be made) to place such splendid work as
that of the Messrs. Stevens in a light which shall reveal both its
variety and extent and its immense importance.
While Fulton was introducing the steamboat upon the waters of New York
Bay and the Hudson River, and while the Stevenses, father and sons,
were rapidly bringing out a fleet of steamers on the Delaware River
and Bay, other mechanics were preparing to contest the field with them
as opportunity offered, and as legislative acts authorizing monopoly
expired by limitation or were repealed.
About 1821, Robert L. Thurston, John Babcock, and Captain Stephen T.
Northam, of Newport, R. I., commenced building steamboats, beginning
with a small craft intended for use at Slade's Ferry, on an arm of
Narragansett Bay, near Fall River. They afterward built vessels to ply
on Long Island Sound. One of their earliest boats was the Babcock,
built at Newport in 1826. The engine was built by Thurston and
Babcock, at Portsmouth, R. I. They were assisted in their work by
Richard Sanford, and with funds by Northam. The engine was of 10 or 12
inches diameter of cylinder, and 3 or 4 feet stroke of piston. The
boiler was a form of "pipe-boiler," subsequently (1824) patented by
Babcock. The water used was injected into the hot boiler as fast as
required to furnish steam, no water being retained in the
steam-generator. This boat was succeeded, in 1827-'28, by a larger
vessel, the Rushlight, for which the engine was built by James P.
Allaire, at New York, while the boat was built at Newport. The boilers
of both vessels had tubes of cast-iron. The smaller of these boats was
of 80 tons burden; it steamed from Newport to Providence, 30 miles, in
3-1/2 hours, and to New York, a distance of 175 miles, in 25 hours,
using 1-3/4 cord of wood.[82] Thurston and Babcock subsequently
removed to Providence, where the latter soon died. Thurston continued
to build steam-engines at this place until nearly a half-century
later, dying in 1874.[83] The establishment founded by him, after
various changes, became the Providence Steam-Engine Works.
[82] _American Journal of Science_, March, 1827; _London Mechanics'
Magazine_, June 16, 1827.
[83] "New Universal Cyclopaedia," vol. iv., 1878.
James P. Allaire, of New York, the West Point Iron Foundery, at West
Point, on the Hudson River, and Daniel Copeland and his son, Charles
W. Copeland, on the Connecticut River, were also early builders of
engines for steam-vessels. Daniel Copeland was probably the first
(1850) to adopt a slide-valve working with a lap to secure the
expansion of steam. His steamboats were then usually stern-wheel
vessels, and were built to ply on several routes on the Connecticut
River and Long Island Sound. The son, Charles W. Copeland,
went to West Point, and while there designed some heavy marine
steam-machinery, and subsequently designed several steam
vessels-of-war for the United States Navy. He was the earliest
designer of iron steamers in the United States, building the Siamese
in 1838. This steamer was intended for use on Lake Pontchartrain and
the canal to New Orleans. It had two hulls, was 110 feet long, and
drew but 22 inches of water, loaded. The two horizontal non-condensing
engines turned a single paddle-wheel placed between the two hulls,
driving the boat 10 miles an hour. The hull was constructed of plates
of iron 10 feet long, formed on blocks after having been heated in a
furnace constructed especially for the purpose. The frames were of
T-iron, which was probably here used for the first time. The same
engineer, associated with Samuel Hart, a well-known naval constructor,
built, in 1841, for the United States Navy, the iron steamer Michigan,
a war-vessel intended for service on the great northern lakes. This
vessel is still in service, and in good order. The hull is 162-1/2
feet in length, 27 feet in breadth, and 12-1/2 feet in depth,
measuring 500 tons. The frames were made of T-iron, stiffened by
reverse bars of L-iron. The keel-plate was 5/8 inch thick, the bottom
plates 3/8, and the sides 3/16 inch. The deck-beams were of iron, and
the vessel, as a whole, was a good specimen of iron-ship building.
During the period from 1830 to 1840, a considerable number of the now
standard details of steam-engine and steamboat construction were
devised or introduced by Copeland. He was probably the first to use
(on the Fulton, 1840) an independent engine to drive the blowing-fans
where an artificial draught was required. He made a practice of
fitting his steamers with a "bilge-injection," by means of which the
vessel could be freed of water, through the condenser and air-pump,
when leaking seriously; the condensing-water is, in such a case, taken
from inside the vessel, instead of from the sea. This is probably an
American device. It was in use in the United States previously to
1835, as was the use of anthracite coal on steamers, which was
continued by Copeland in manufacturing and in air-furnaces, as well as
on steamboats. He also modified the form of Stevens's double-poppet
valve, giving it such shape that it was comparatively easy to grind it
tight and to keep it in order.
In 1825, James P. Allaire, of New York, built compound engines for the
Henry Eckford, and subsequently constructed similar engines for
several other steamers, one of which, the Sun, made the trip from New
York to Albany in 12 hours 18 minutes. He used steam at 100 pounds
pressure. Erastus W. Smith afterward introduced this form of engine on
the Great Lakes, and still later they were introduced into British
steamers. The machinery of the steamer Buckeye State was constructed
at the Allaire Works, New York, in 1850, from the designs of John
Baird and Erastus W. Smith, the latter being the designing and
constructing engineer. The steamer was placed on the route between
Buffalo, Cleveland, and Detroit, in 1851, and gave most satisfactory
results, consuming less than two-thirds the fuel required by a similar
vessel of the same line fitted with the single-cylinder engine. The
steam-cylinders of this engine were placed one within the other, the
low-pressure exterior cylinder being annular. They were 37 and 80
inches in diameter respectively, and the stroke was 11 feet. Both
pistons were connected to one cross-head, and the general arrangement
of the engine was similar to that of the common form of beam-engine.
The steam-pressure was from 70 to 75 pounds--about the maximum
pressure adopted a quarter of a century later on transatlantic lines.
This steamer was of high speed, as well as economical of fuel.
In the year 1830, there were 86 steamers on the Hudson River and in
Long Island Sound.
During the early part of the nineteenth century, the introduction of
the steamboat upon the waters of the great rivers of the interior of
the United States was one of the most notable details of its history.
Inaugurated by the unsuccessful experiment of Evans, the building of
steamboats on those waters, once commenced, never ceased; and a
generation after Fitch's burial on the shore of the Ohio, his last
wish--that he might lie "where the song of the boatman would enliven
the stillness of his resting-place, and the music of the steam-engine
soothe his spirit"--was fulfilled day by day unceasingly.
Nicholas J. Roosevelt was, as has been already stated, the first to
take a steamboat down the great rivers. His boat was built at
Pittsburgh in 1811, under an arrangement with Fulton and Livingston,
from Fulton's plans. It was called the "New Orleans," was of about 200
tons burden, and was propelled by a stern-wheel, assisted, when the
winds were favorable, by sails carried on two masts. The hull was 138
feet long, 30 feet beam, and the cost of the whole, including engines,
was about $40,000. The builder, with his family, an engineer, a pilot,
and six "deck-hands," left Pittsburgh in October, 1811, reaching
Louisville in 70 hours (steaming about 10 miles an hour), and New
Orleans in 14 days, steaming from Natchez.
The next steamers built on Western waters were probably the Comet and
the Vesuvius, both of which were in service some time. The Comet was
finally laid aside, and the engine used to drive a mill, and the
Vesuvius was destroyed by the explosion of her boilers. As early as
1813 there were two shops at Pittsburgh building steam-engines.
Steamboat-building now became an important and lucrative business in
the West; and it is stated that as early as 1840 there were a thousand
steamers on the Mississippi and its tributaries.
In the Washington, built at Wheeling, Va., in 1816, under the
direction of Captain Henry M. Shreve, the boilers, which had
previously been placed in the hold, were carried on the main-deck, and
a "hurricane-deck" was built over them. Shreve substituted two
horizontal direct-acting engines for the single upright engine used by
Fulton, drove them by high-pressure steam without condensation, and
attached them, one on each side the boat, to cranks placed at right
angles. He adopted a cam cut-off expanding the steam considerably, and
the flue-boiler of Evans. At that time the voyage from New Orleans to
Louisville occupied three weeks, and Shreve was made the subject of
many witticisms when he predicted that the time would ultimately be
shortened to ten days. It is now made in four days. The Washington was
seized at New Orleans, in 1817, by order of Livingston, who claimed
that his rights included the monopoly of the navigation of the
Mississippi and its tributaries. The courts decided adversely on this
claim, and the release of the Washington was the act which removed
every obstacle to the introduction of steam-navigation throughout the
United States.
The first steamer on the Great Lakes was the Ontario, built in 1816,
at Sackett's Harbor. Fifteen years later, Western steamboats had taken
the peculiar form which has since usually distinguished them.
The use of the steam-engine for ocean-navigation kept pace with its
introduction on inland waters. Begun by Robert L. Stevens in the
United States, in the year 1808, and by his contemporaries, Bell and
Dodd, in Great Britain, it steadily and rapidly advanced in
effectiveness and importance, and has now nearly driven the sailing
fleet from the ocean. Transatlantic steam-navigation began with the
voyage of the American steamer Savannah from Savannah, Ga., to St.
Petersburg, Russia, _via_ Great Britain and the North-European ports,
in the year 1819. Fulton, not long before his death, planned a vessel,
which it was proposed to place in service in the Baltic Sea; but
circumstances compelled a change of plan finally, and the steamer was
placed on a line between Newport, R. I., and the city of New York; and
the Savannah, several years later, made the voyage then proposed for
Fulton's ship. The Savannah measured 350 tons, and was constructed by
Crocker & Fickett, at Corlears Hook, N. Y. She was purchased by Mr.
Scarborough, of Savannah, who placed Captain Moses Rogers, previously
in command of the Clermont and of Stevens's boat, the Ph[oe]nix, in
charge. The ship was fitted with steam-machinery and paddle-wheels,
and sailed for Savannah April 27, 1819, making the voyage successfully
in seven days. From Savannah, the vessel sailed for Liverpool May
26th, and arrived at that port June 20th. During this trip the engines
were used 18 days, and the remainder of the voyage was made under
sail. From Liverpool the Savannah sailed, July 23d, for the Baltic,
touching at Copenhagen, Stockholm, St. Petersburg, and other ports. At
St. Petersburg, Lord Lyndock, who had been a passenger, was landed;
and, on taking leave of the commander of the steamer, the
distinguished guest presented him with a silver tea-kettle, suitably
inscribed with a legend referring to the importance of the event which
afforded him the opportunity. The Savannah left St. Petersburg in
November, passing New York December 9th, and reaching Savannah in 50
days from the date of departure, stopping four days at Copenhagen,
Denmark, and an equal length of time at Arundel, Norway. Several
severe gales were met in the Atlantic, but no serious injury was done
to the ship.
The Savannah was a full-rigged ship. The wheels were turned by an
inclined direct-acting low-pressure engine, having a steam-cylinder 40
inches in diameter and 6 feet stroke of piston. The paddle-wheels were
of wrought-iron, and were so attached that they could be detached and
hoisted on board when it was desired. After the return of the ship to
the United States, the machinery was removed and was sold to the
Allaire Works, of New York. The steam-cylinder was exhibited by the
purchasers at the "World's Fair" at New York thirty years later. The
vessel was employed, as a sailing-vessel, on a line between New York
and Savannah, and was finally lost in the year 1822. Under sail, with
a moderate breeze, this ship is said to have sailed about three knots,
and to have steamed five knots. Pine-wood was used as the fuel, which
fact accounts for the necessity of making the transatlantic voyage
partly under sail.
Renwick states that another vessel, ship-rigged and fitted with a
steam-engine, was built at New York in 1819, to ply between New York
and Charleston, and to New Orleans and Havana, and that it proved
perfectly successful as a steamer, having good speed, and proving an
excellent sea-boat. The enterprise was, however, pecuniarily a
failure, and the vessel was sold to the Brazilian Government after the
removal of the engine. In 1825 the steamer Enterprise made a voyage to
India, sailing and steaming as the weather and the supply of fuel
permitted. The voyage occupied 47 days.
Notwithstanding these successful passages across the ocean, and the
complete success of the steamboat in rivers and harbors, it was
asserted, as late as 1838, by many who were regarded as authority,
that the passage of the ocean by steamers was quite impracticable,
unless possibly they could steam from the coasts of Europe to
Newfoundland or to the Azores, and, replenishing their coal-bunkers,
resume their voyages to the larger American ports. The voyage was,
however, actually accomplished by two steamers in the year just
mentioned. These were the Sirius, a ship of 700 tons and of 250
horse-power, and the Great Western, of 1,340 tons and 450 horse-power.
The latter was built for this service, and was a large ship for that
time, measuring 236 feet in length. Her wheels were 28 feet in
diameter, and 10 feet in breadth of face. The Sirius sailed from Cork
April 4, 1838, and the Great Western from Bristol April 8th, both
arriving at New York on the same day--April 23d--the Sirius in the
morning, and the Great Western in the afternoon.
The Great Western carried out of Bristol 660 tons of coal. Seven
passengers chose to take advantage of the opportunity, and made the
voyage in one-half the time usually occupied by the sailing-packets of
that day. Throughout the voyage the wind and sea were nearly ahead,
and the two vessels pursued the same course, under very similar
conditions. Arriving at New York, they were received with the greatest
possible enthusiasm. They were saluted by the forts and the men-of-war
in the harbor; the merchant-vessels dipped their flags, and the
citizens assembled on the Battery, and, coming to meet them in boats
of all kinds and sizes, cheered heartily. The newspapers of the time
were filled with the story of the voyage and with descriptions of the
steamers themselves and of their machinery.
A few days later the two steamers started on their return to Great
Britain, the Sirius reaching Falmouth safely in 18 days, and the Great
Western making the voyage to Bristol in 15 days, the latter meeting
with head-winds and working, during a part of the time, against a
heavy gale and in a high sea, at the rate of but two knots an hour.
The Sirius was thought too small for this long and boisterous route,
and was withdrawn and replaced on the line between London and Cork,
where the ship had previously been employed. The Great Western
continued several years in the transatlantic trade.
Thus these two voyages inaugurated a transoceanic steam-service, which
has steadily grown in extent and in importance. The use of steam-power
for this work of extended ocean-transportation has never since been
interrupted. During the succeeding six years the Great Western made 70
passages across the Atlantic, occupying on the voyages to the westward
an average of 15-1/2 days, and eastward 13-1/2. The quickest passage
to New York was made in May, 1843, in 12 days and 18 hours, and the
fastest steaming was logged 12 months earlier, when the voyage from
New York was made in 12 days and 7 hours.
Meantime, several other steamers were built and placed in the
transatlantic trade. Among these were the Royal William, the British
Queen, the President, the Liverpool, and the Great Britain. The
latter, the finest of the fleet, was launched in 1843. This steamer
was 300 feet long, 50 feet beam, and of 1,000 horse-power. The hull
was of iron, and the whole ship was an example of the very best work
of that time. After several voyages, this vessel went ashore on the
coast of Ireland, and there remained several weeks, but was finally
got off, without having suffered serious injury--a remarkable
illustration of the stanchness of an iron hull when well built and of
good material. The vessel was repaired, and many years afterward was
still afloat, and engaged in the transportation of passengers and
merchandise to Australia.
The "Cunard Line" of transatlantic steamers was established in the
year 1840. The first of the line--the Britannia--sailed from Liverpool
for New York, July 4th of that year, and was followed, on regular
sailing-days, by the other three of the four ships with which the
company commenced business. These four vessels had an aggregate
tonnage of 4,600 tons, and their speed was less than eight knots.
To-day, the tonnage of a single vessel of the fleet exceeds that of
the four; the total tonnage has risen to many times that above given.
There are 50 steamers in the line, aggregating nearly 50,000
horse-power. The speed of the steamships of the present time is double
that of the vessels of that date, and passages are not infrequently
made in eight days.
The form of steam-engine in most general use at this time, on
transatlantic steamers, was that known as the "side-lever engine." It
was first given the standard form by Messrs. Maudsley & Co., of
London, about 1835, and was built by them for steamers supplied to the
British Government for general mail service.
The steam-vessels of the time are well represented in the accompanying
engraving (Fig. 91) of the steamship Atlantic--a vessel which was
shortly afterward (1851) built as the pioneer steamer of the American
"Collins Line." This steamship was one of several which formed the
earliest of American steamship-lines, and is one of the finest
examples of the type of paddle-steamers which was finally superseded
by the later screw-fleets. The "Collins Line" existed but a very few
years, and its failure was probably determined as much by the evident
and inevitable success of screw-propulsion as by the difficulty of
securing ample capital, complete organization, and efficient general
management. This steamer was built at New York--the hull by William
Brown, and the machinery by the Novelty Iron-Works. The length of the
hull was 276 feet, its breadth 45 feet, and the depth of hold 31-1/2
feet. The width over the paddle-boxes was 75 feet. The ship measured
2,860 tons. The form of the hull was then peculiar in the fineness of
its lines; the bow was sharp, and the stern fine and smooth, and the
general outline such as best adapted the ship for high speed. The main
saloon was about 70 feet long, and the dining-room was 60 feet in
length and 20 feet wide. The state-rooms were arranged on each side
the dining "saloon," and accommodated 150 passengers. These vessels
were beautifully fitted up, and with them was inaugurated that
wonderful system of passenger-transportation which has since always
been distinguished by those comforts and conveniences which the
American traveler has learned to consider his by right.
[Illustration: FIG. 91.--The Atlantic, 1851.]
The machinery of these ships was, for that time, remarkably powerful
and efficient. The engines were of the side-lever type, as
illustrated in Fig. 92, which represents the engine of the Pacific,
designed by Mr. Charles W. Copeland, and built by the Allaire Works.
[Illustration: FIG. 92.--The Side-Lever Engine, 1849.]
In this type of engine, as is seen, the piston-rod was attached to a
cross-head working vertically, from which, at each side, links, _B C_,
connected with the "side-lever," _D E F_. The latter vibrated about a
"main centre" at _E_, like the overhead beam of the more common form
of engine; from its other end, a "connecting-rod," _H_, led to the
"cross-tail," _W_, which was, in turn, connected to the crank-pin,
_I_. The condenser, _M_, and air-pump, _Q_, were constructed in the
same manner as those of other engines, their only peculiarities being
such as were incident to their location between the cylinder, _A_, and
the crank, _I J_. The paddle-wheels were of the common "radial" form,
covered in by paddle-boxes so strongly built that they were rarely
injured by the heaviest seas.
These vessels surpassed, for a time, all other sea-going steamers in
speed and comfort, and made their passages with great regularity. The
minimum length of voyage of the Baltic and Pacific, of this line, was
9 days 19 hours.
During the latter part of the period the history of which has been
here given, the marine steam-engine became subject to very marked
changes in type and in details, and a complete revolution was effected
in the method of propulsion. This change has finally resulted in the
universal adoption of a new propelling instrument, and in driving the
whole fleet of paddle-steamers from the ocean. The Great Britain was a
screw-steamer.
The screw-propeller, which, as has been stated, was probably first
proposed by Dr. Hooke in 1681, and by Dr. Bernouilli, of Groningen, at
about the middle of the eighteenth century, and by Watt in 1784, was,
at the end of the century, tried experimentally in the United States
by David Bushnell, an ingenious American, who was then conducting the
experiments with torpedoes which were the cause of the incident which
originated that celebrated song by Francis Hopkinson, the "Battle of
the Kegs," using the screw to propel one of his submarine boats, and
by John Fitch, and by Dallery in France.
Joseph Bramah, of Great Britain, May 9, 1785, patented a
screw-propeller identical in general arrangement with those used
to-day. His sketch exhibits a screw, apparently of very fair shape,
carried on an horizontal shaft, which passes out of the vessel through
a stuffing-box, the screw being wholly submerged. Bramah does not seem
to have put his plan in practice. It was patented again in England,
also, by Littleton in 1794, and by Shorter in 1800.
John Stevens, however, first gave the screw a practically useful
form, and used it successfully, in 1804 and 1805, on the single and
the twin screw boats which he built at that time. This propelling
instrument was also tried by Trevithick, who planned a vessel to be
propelled by a steam-engine driving a screw, at about this time, and
his scheme was laid before the Navy Board in the year 1812. His plans
included an iron hull. Francis Pettit Smith tried the screw also in
the year 1808, and subsequently.
Joseph Ressel, a Bohemian, proposed to use a screw in the propulsion
of balloons, about 1812, and in the year 1826 proposed its use for
marine propulsion. He is said to have built a screw-boat in the year
1829, at Trieste, which he named the Civetta. The little craft met
with an accident on the trial-trip, and nothing more was done.
The screw was finally brought into general use through the exertions
of John Ericsson, a skillful Swedish engineer, who was residing in
England in the year 1836, and of Mr. F. P. Smith, an English farmer.
Ericsson patented a peculiar form of screw-propeller, and designed a
steamer 40 feet in length, of 8 feet beam, and drawing 3 feet of
water. The screw was double, two shafts being placed the one within
the other, revolving in opposite directions, and carrying the one a
right-hand and the other a left-hand screw. These screws were 5-1/4
feet in diameter. On her trial-trip this little steamer attained a
speed of 10 miles an hour. Its power as a "tug" was found to be very
satisfactory; it towed a schooner of 140 tons burden at the rate of 7
miles, and the large American packet-ship Toronto was towed on the
Thames at a speed of 5 miles an hour.
Ericsson endeavored to interest the British Admiralty in his
improvements, and succeeded only so far as to induce the Lords of the
Admiralty to make an excursion with him on the river. No interest was
awakened in the new system, and nothing was done by the naval
authorities. A note to the inventor from Captain Beaufort--one of the
party--was received shortly afterward, in which it was stated that
the excursionists had not found the performance of the little vessel
to equal their hopes and expectations. All the interests of the then
existing engine-building establishments were opposed to the
innovation, and the proverbial conservatism of naval men and naval
administrations aided in procuring the rejection of Ericsson's plans.
Fortunately for the United States, it happened, at that time, that we
had in Great Britain both civil and naval representatives of greater
intelligence, or of greater boldness and enterprise. The consul at
Liverpool was Mr. Francis B. Ogden, of New Jersey, a gentleman who was
somewhat familiar with the steam-engine and with steam-navigation. He
had seen Ericsson's plans at an earlier period, and had at once seen
their probable value. He was sufficiently confident of success to
place capital at the disposal of the inventor. The little screw-boat
just described was built with funds of which he furnished a part, and
was named, in his honor, the Francis B. Ogden.
Captain Robert F. Stockton, an officer of the United States Navy, and
also a resident of New Jersey, was in London at the time, and made an
excursion with Ericsson on the Ogden. He was also at once convinced of
the value of the new method of application of steam-power to
ship-propulsion, and gave the engineer an order to build two iron
screw-steamboats for use in the United States. Ericsson was induced,
by Messrs. Ogden and Stockton, to take up his residence in the United
States.[84] The Stockton was sent over to the United States in April,
1839, under sail, and was sold to the Delaware & Raritan Canal
Company. Her name was changed, and, as the New Jersey, she remained in
service many years.
[84] This distinguished inventor is still a resident of New York
(1878).
The success of the boat built by Ericsson was so evident that,
although the naval authorities remained inactive, a private company
was formed, in 1839, to work the patents of F. P. Smith, and this
"Ship-Propeller Company" built an experimental craft called the
Archimedes, and its trial-trip was made October 14th of the same year.
The speed attained was 9.64 miles an hour. The result was in every
respect satisfactory, and the vessel, subsequently, made many voyages
from port to port, and finally circumnavigated the island of Great
Britain. The proprietors of the ship were not pecuniarily successful
in their venture, however, and the sale of the vessel left the company
a heavy loser. The Archimedes was 125 feet long, of 21 feet 10 inches
beam, and 10 feet draught, registering 232 tons. The engines were
rated at 80 horse-power. Smith's earlier experiments (1837) were made
with a little craft of 6 tons burden, driven by an engine having a
steam-cylinder 6 inches in diameter and 15 inches stroke of piston.
The funds needed were furnished by a London banker--Mr. Wright.
Bennett Woodcroft had also used the screw experimentally as early as
1832, on the Irwell, near Manchester, England, in a boat of 55 tons
burden. Twin-screws were used, right and left handed respectively;
they were each two feet in diameter, and were given an expanding
pitch. The boat attained a speed of four miles an hour.
Experiments made subsequently (1843) with this form of screw, and in
competition with the "true" screw of Smith, brought out very
distinctly the superiority of the former, and gave some knowledge of
the proper proportions for maximum efficiency. In later examples of
the Woodcroft screw, the blades were made detachable and adjustable--a
plan which is still a usual one, and which has proved to be, in some
respects, very convenient.
When Ericsson reached the United States, he was almost
immediately given an opportunity to build the Princeton--a large
screw-steamer--and at about the same time the English and French
Governments also had screw-steamers built from his plans, or from
those of his agent in England, the Count de Rosen. In these latter
ships--the Amphion and the Pomona--the first horizontal direct-acting
engines ever built were used, and they were fitted with double-acting
air-pumps, having canvas valves and other novel features. The great
advantages exhibited by these vessels over the paddle-steamers of the
time did for screw-propulsion what Stephenson's locomotive--the
Rocket--did for railroad locomotion ten years earlier.
Congress, in 1839, had authorized the construction of three
war-vessels, and the Secretary of the Navy ordered that two be at once
built in the succeeding year. Of these, one was the Princeton, the
screw-steamer of which the machinery was designed by Ericsson. The
length of this vessel was 164 feet, beam 30-1/2 feet, and depth 21-1/2
feet. The ship drew from 16-1/2 to 18 feet of water, displacing at
those draughts 950 and 1,050 tons. The hull had a broad, flat floor,
with sharp entrance and fine run, and the lines were considered at
that time remarkably fine.
The screw was of gun-bronze, six-bladed, and was 14 feet in diameter
and of 35 feet pitch; i. e., were there no slip, the screw working as
if in a solid nut, the ship would have been driven forward 35 feet at
each revolution.
The engines were two in number, and very peculiar in form; the
cylinder was, in fact, a _semi_-cylinder, and the place of the
piston-rod, as usually built, was taken by a vibrating shaft, or
"rock-shaft," which carried a piston of rectangular form, and which
vibrated like a door on its hinges as the steam was alternately let
into and exhausted from each side of it. The great rock-shaft carried,
at the outer end, an arm from which a connecting-rod led to the crank,
thus forming a "direct-acting engine."
The draught in the boilers was urged by blowers. Ericsson had adopted
this method of securing an artificial draught ten years before, in one
of his earlier vessels, the Corsair. The Princeton carried a XII-inch
wrought-iron gun. This gun exploded after a few trials, with terribly
disastrous results, causing the death of several distinguished men,
including members of the President's cabinet.
The Princeton proved very successful as a screw-steamer, attaining a
speed of 13 knots, and was then considered very remarkably fast.
Captain Stockton, who commanded the vessel, was most enthusiastic in
praise of her.
Immediately there began a revolution in both civil and naval
ship-building, which progressed with great rapidity. The Princeton was
the first of the screw-propelled navy which has now entirely displaced
the older type of steam-vessel. The introduction of the screw now took
place with great rapidity. Six steamers were fitted with Ericsson's
screw in 1841, 9 in 1842, and nearly 30 in the year 1843.
In Great Britain, France, Germany, and other European countries, the
revolution was also finally effected, and was equally complete. Nearly
all sea-going vessels built toward the close of the period here
considered were screw-steamers, fitted with direct-acting,
quick-working engines. It was, however, many years before the
experience of engineers in the designing and in the construction and
management of this new machinery enabled them to properly proportion
it for the various kinds of service to which they were called upon to
adapt it. Among other modifications of earlier practice introduced by
Ericsson was the surface-condenser with a circulating pump driven by a
small independent engine.
The screw was found to possess many advantages over the paddle-wheel
as an instrument for ship-propulsion. The cost of machinery was
greatly reduced by its use; the expense of maintenance in working
order was, however, somewhat increased. The latter disadvantage was,
nevertheless, much more than compensated by an immense increase in the
economy of ship-propulsion, which marked the substitution of the new
instrument and its impelling machinery.
When a ship is propelled by paddles, the motion of the vessel creates,
in consequence of the friction of the fluid against the sides and
bottom, a current of water which flows in the direction in which the
ship is moving, and forms a current following the ship for a time, and
finally losing all motion by contact with the surrounding mass of
water. All the power expended in the production of this great stream
is, in the case of the paddle-steamer, entirely lost. In
screw-steamers, however, the propelling instrument works in this
following current, and the tendency of its action is to bring the
agitated fluid to rest, taking up and thus restoring, usefully, a
large part of that energy which would otherwise have been lost. The
screw is also completely covered by the water, and acts with
comparative efficiency in consequence of its submersion. The rotation
of the screw is comparatively rapid and smooth, also, and this permits
the use of small, light, fast-running engines. The latter condition
leads to economy of weight and space, and consequently saves not only
the cost of transportation of the excess of weight of the larger kind
of engine, but, leaving so much more room for paying cargo, the gain
is found to be a double one. Still further, the quick-running engine
is, other things being equal, the most economical of steam; and thus
some expense is saved not only in the purchase of fuel, but in its
transportation, and some still additional gain is derived from the
increased amount of paying cargo which the vessel is thus enabled to
carry. The change here described was thus found to be productive of
enormous direct gain. Indirectly, also, some advantage was derived
from the greater convenience of a deck clear from machinery and the
great paddle-shaft, in the better storage of the lading, the greater
facility with which the masts and sails could be fitted and used; and
directly, again, in clear sides unencumbered by great paddle-boxes
which impeded the vessel by catching both sea and wind.
The screw was, for some years, generally regarded as simply auxiliary
in large vessels, assisting the sails. Ultimately the screw became
the essential feature, and vessels were lightly sparred and were given
smaller areas of sail, the latter becoming the auxiliary power.
In November of the year 1843, the screw-steamer Midas, Captain Poor, a
small schooner-rigged craft, left New York for China, on probably the
first voyage of such length ever undertaken by a steamer; and in the
following January the Edith, Captain Lewis, a bark-rigged
screw-vessel, sailed from the same port for India and China. The
Massachusetts, Captain Forbes, a screw-steamship of about 800 tons,
sailed for Liverpool September 15, 1845, the first voyage of an
American transatlantic passenger-steamer since the Savannah's pioneer
adventure a quarter of a century before. Two years later, American
enterprise had placed both screw and paddle steamers on the rivers of
China--principally through the exertions of Captain R. B. Forbes--and
steam-navigation was fairly established throughout the world.
On comparing the screw-steamer of the present time with the best
examples of steamers propelled by paddle-wheels, the superiority of
the former is so marked that it may cause some surprise that the
revolution just described should have progressed no more rapidly. The
reason of this slow progress, however, was probably that the
introduction of the rapidly-revolving screw, in place of the
slow-moving paddle-wheel, necessitated a complete revolution in the
design of their steam-engines; and the unavoidable change from the
heavy, long-stroked, low-speed engines previously in use, to the light
engines, with small cylinders and high piston-speed, called for by the
new system of propulsion, was one that necessarily occurred slowly,
and was accompanied by its share of those engineering blunders and
accidents that invariably take place during such periods of
transition. Engineers had first to learn to design such engines
as should be reliable under the then novel conditions of
screw-propulsion, and their experience could only be gained through
the occurrence of many mishaps and costly failures. The best
proportions of engines and screws, for a given ship, were determined
only by long experience, although great assistance was derived from
the extensive series of experiments made with the French steamer
Pelican. It also became necessary to train up a body of engine-drivers
who should be capable of managing these new engines; for they required
the exercise of a then unprecedented amount of care and skill.
Finally, with the accomplishment of these two requisites to success
must simultaneously occur the enlightenment of the public,
professional as well as non-professional, in regard to their
advantages. Thus it happens that it is only after a considerable time
that the screw attained its proper place as an instrument of
propulsion, and finally drove the paddle-wheel quite out of use,
except in shoal water.
Now our large screw-steamers are of higher speed than any
paddle-steamers on the ocean, and develop their power at far less
cost. This increased economy is due not only to the use of a more
efficient propelling instrument, and to changes already described, but
also, in a great degree, to the economy which has followed as a
consequence of other changes in the steam-engine driving it. The
earliest days of screw-propulsion witnessed the use of steam of from 5
to 15 pounds pressure, in a geared engine using jet-condensation, and
giving a horse-power at an expense of perhaps 7 to 10, or even more,
pounds of coal per hour. A little later came direct-acting engines
with jet-condensation and steam at 20 pounds pressure, costing about 5
or 6 pounds per horse-power per hour. The steam-pressure rose a little
higher with the use of greater expansion, and the economy of fuel was
further improved. The introduction of the surface-condenser, which
began to be generally adopted some ten years ago, brought down the
cost of power to from 3 to 4 pounds in the better class of engines. At
about the same time, this change to surface-condensation helping
greatly to overcome those troubles arising from boiler-incrustation
which had prevented the rise of steam-pressure above about 25 pounds
per square inch, and as, at the same time, it was learned by engineers
that the deposit of lime-scale in the marine boiler was determined by
temperature rather than by the degree of concentration, and that all
the lime entering the boiler was deposited at the pressure just
mentioned, a sudden advance took place. Careful design, good
workmanship, and skillful management, made the surface-condenser an
efficient apparatus; and, the dangers of incrustation being thus
lessened, the movement toward higher pressures recommenced, and
progressed so rapidly that now 75 pounds per square inch is very
usual, and more than 125 pounds has since been attained.
The close of this period was marked by the construction of the most
successful types of paddle-steamers, the complete success of
transoceanic steam-transportation, the introduction of the
screw-propeller and the peculiar engine appropriate to it, and,
finally, a general improvement, which had finally become marked both
in direction and in rapidity of movement, leading toward the use of
higher steam-pressure, greater expansion, lighter and more
rapidly-working machinery, and decidedly better design and
construction, and the use of better material. The result of these
changes was seen in economy of first cost and maintenance, and the
ability to attain greater speed, and to assure greater safety to
passengers and less risk to cargo.
The introduction of the changes just noted finally led to the last
great change in the form of the marine steam-engine, and a revolution
was inaugurated, which, however, only became complete in the
succeeding period. The non-success of Hornblower and of Wolff, and
others who had attempted to introduce the "compound" or
double-cylinder engine on land, had not convinced all engineers that
it might not yet be made a successful rival of the then standard type;
and the three or four steamers which were built for the Hudson River
at the end of the first quarter of the nineteenth century are said to
have been very successful vessels. Carrying 75 to 100 pounds of steam
in their boilers, the Swiftsure and her contemporaries were by that
circumstance well fitted to make that form of engine economically a
success. This form of engine was built occasionally during the
succeeding quarter of a century, but only became a recognized standard
type after the close of the epoch to the history of which this chapter
is devoted. That latest and greatest advance in the direction of
increased efficiency in the marine steam-engine was, however,
commenced very soon after Watt's death, and its completion was the
work of nearly a half-century.
[Illustration]