the two necessary elements in a radical advance in marine engineering.
Neither of these was a new proposal;[3] several patents had been taken
out for the former at a very early date, both in America and in
England; and in 1838 the Wilberforce, a boat running between London
and Hull, was so fitted. Very high pressures, from almost the very
beginning, had been carried in the steamers on our Western waters; and
in 1811 Oliver Evans published, in Philadelphia, a pamphlet dealing
with the subject, in which he advocated pressures of at least 100 to
120 pounds per square inch, and patented a boiler which was the parent
of the long, cylindrical type which came into such general use in our
river navigation. The sea-going public resolutely resisted the change
to high pressures for nearly forty years, there being a very slow and
gradual advance from 1 and 2 pounds to the 8 and 9 carried by the Great
Britain and Britannia. In 1850 the Arctic carried 18 and in 1856 25 was
not uncommon. Some of the foremost early engineers favored cast-iron
boilers (see evidence before parliamentary committee, 1817); and the
boiler in general use in England up to 1850 was a great rectangular
box, usually with three furnaces and flues, all the faces of which were
planes.[4]
[Illustration: Longitudinal Section of the Warship Duilio.]
Though tubular boilers did not displace the flue boiler in British
practice to any great degree before 1850, many examples were in use in
America at that date, but chiefly in other than sea-going steamers.
Robert L. Stevens, of Hoboken, built as early as 1832 “the now standard
form of return tubular boilers for moderate pressures” (Professor R.
H. Thurston). But it worked its way into sea practice very slowly; and
the multitubular boiler, in any of its several forms, cannot be said to
have been fairly adopted in either American or British sea-going ships
before the date first mentioned, though employed in the Hudson River
and Long Island Sound steamers, in one of the former of which, the
Thomas Powell, built in 1850, a steam pressure of 50 pounds was used.
[Illustration: The Britannic.]
There had been this slow and gradual advance in ocean steam pressures,
with a consequent reduction in coal expenditure, when in 1856 came
a movement in the direction of economy by the introduction of the
compound engine, by Messrs. Randolph Elder & Co. (later John Elder
& Co.), which was soon to develop into a revolution in marine steam
enginery. The Pacific Steam Navigation Company has the credit of first
accepting this change in applying it to their ships, the Valparaiso
and Inca. The original pressure used was 25 pounds to the inch: the
cylinders were 50 and 90 inches in diameter, and the piston speed from
230 to 250 feet per minute. The idea of using steam expansively by this
means was of course not new, as it dates back to Hornblower (1781),
but with the low pressures which had been used at sea there was no
reason for its adoption afloat. Difficulties were experienced by the
Pacific company with their earlier engines, but the line adhered to
their change, and for nearly fourteen years were almost alone in their
practice.
These changes made the use of a cylindrical boiler necessary, as the
form best able to withstand the increased pressure. The old box-like
shape has disappeared; and if the shade of Oliver Evans is ever able to
visit us, it must be with an intense feeling of satisfaction to find
his ideas of eighty years since now accepted by all the world.
* * * * *
The date 1870 marks the advent of a new type of ship, in those of the
Oceanic Company, better known as the White Star line, built of iron
by Harland & Wolff, of Belfast—engined with compound engines, and of
extreme length as compared with their breadth. They established a new
form, style, and interior arrangement, which has largely been followed
by other lines, though the extreme disproportion of length and beam
is now disappearing. The Britannic and Germanic, the two largest of
the earlier of this line, are 468 feet in length and 45 feet 3 inches
in beam, carrying 220 cabin passengers and 1,100 in the steerage,
besides 150 crew. They develop 5,000 indicated horse-power, and make
their passage, with remarkable regularity, in about 8 days 10 hours to
Queenstown. The earlier ships of this line, when first built, had a
means of dropping their propeller-shaft so as to immerse more deeply
the screw; so many inconveniences, however, were associated with this
that it was given up. Their general arrangement was a most marked
advance upon that of their predecessors—an excellent move was placing
the saloon forward instead of in the stern, a change almost universally
followed.
In the same year with the Britannic came out the City of Berlin, of the
Inman line, for some years the largest steamer afloat (after the Great
Eastern), being 520 feet in length by 44 feet beam, of 5,000 indicated
power, and in every way a magnificent ship.
The Bothnia and Scythia were also built in 1874, by the Cunard company,
as representatives of the new type, but were smaller than the ships
of the same period built by the Inman and White Star lines. They were
of 6,080 tons displacement and 2,780 indicated horse-power, with a
speed of 13 knots. The pressure carried was 60 pounds. These ships had
by far the largest cargo-carrying capacity (3,000 tons measurement)
and passenger accommodation (340 first-cabin) of any yet built by the
company. With the addition of this great number of steamers, change
was not to be expected for some years; and it was not until 1879, when
the Guion company put afloat the Arizona, that a beginning was made of
the tremendous rivalry which has resulted in putting upon the seas,
not only the wonderful ships which are now running upon the Atlantic,
but in extending greatly the size and speed of those employed in other
service.
Several things had combined in the latter part of this decade to bring
about this advance. The great change between 1860 and 1872, from the
causes already noted, which had reduced coal consumption by one-half,
was followed by the introduction of corrugated flues and steel as
a material for both boilers and hull. With this came still higher
pressures, which were carried from 60 to 80 and 90 pounds. In August,
1881, a very interesting paper was read by Mr. F. C. Marshall, of
Newcastle, before the Institution of Mechanical Engineers, in which
he showed that a saving of 13.37 per cent. in fuel had been arrived
at since 1872. The general type of engine and boiler had remained the
same in these nine years, but the increased saving had been due chiefly
to increased pressures. It is curious that at the reading of both the
paper by Sir Frederick Bramwell, in 1872, and that of Mr. Marshall, in
1881, there should have been pretty generally expressed a feeling that
something like a finality had been reached. So little was this opinion
true that, though over thirteen per cent. saving had been effected
between these two dates, a percentage of gain more than double this was
to be recorded between the latter date and 1886. In these matters it
is dangerous to prophesy; it is safer to believe all things possible.
Certainly the wildest dreamer of 1872 did not look forward to crossing
the Atlantic at 20 knots as a not unusual speed.
[Illustration: The Etruria]
In 1874 triple-expansion engines had been designed for the Propontis
by Mr. A. C. Kirk, of Napier & Sons, of Glasgow, which, on account
of failure in the boilers which were used, did not give at first the
results hoped for. In 1881 the Messrs. Napier fitted the Aberdeen with
engines of the same kind, steam at 125 pounds pressure per square
inch being used. In the next two years the change proceeded slowly,
but by 1885 the engineering mind had so largely accepted it that
a very large proportion of the engines built in that year were on
this principle, and at the present it may be regarded as being fully
accepted as was the compound engine ten years since. The saving in
fuel is generally reckoned at from twenty to twenty-five per cent.,
or, to put it more graphically, in the words of Mr. Parker, Chief
Engineer Surveyor of Lloyds, in his interesting paper, read in July,
1886, before the Institution of Naval Architects: “Two large passenger
steamers, of over 4,500 gross tonnage, having engines of about 6,000
indicated horse-power, built of the same dimensions, from the same
lines, with similar propellers, are exactly alike in every respect,
except so far as their machinery is concerned. One vessel is fitted
with triple-expansion engines, working at a pressure of 145 pounds per
square inch; while the other vessel is fitted with ordinary compound
engines, working at a pressure of 90 pounds per square inch. Both
vessels are engaged in the same trade and steam at the same rate of
speed, viz., 12 knots an hour. The latter vessel in a round voyage of
84 days burns 1,200 tons more coal than the former.”
In the epoch 1879 to 1887 the following great ships had been placed
upon the Liverpool and New York lines, their best speeds to that date
being as shown:
Days. Hours. Minutes.
1. Etruria 6 5 31
2. Umbria (sister ship) slightly longer
3. Oregon 6 10 35
4. America 6 13 44
5. City of Rome 6 18 0
6. Alaska 6 18 37
7. Servia 6 23 55
8. Aurania 7 1 1
The time had thus been shortened much more than half since 1840, and
had been lessened forty per cent. since 1860.
In addition to the ships mentioned, there had been placed upon the
line from Bremen to New York (between 1879 and 1886) touching at
Southampton, England, eight new ships of the North German Lloyd,
which form 28 altogether, the most compact and uniform fleet upon
the Atlantic. The Trave, Saale, and Aller, were then marvels of
splendor and comfort, ranking in speed and power very little short of
the fastest of the Liverpool ships. They, as were the others of the
company’s eight “express” steamers, were built by the great firm of
John Elder & Co., of Glasgow, their machinery being designed by Mr.
Bryce-Douglas, to whose genius was also due that of the Etruria and
Umbria, the Oregon, Arizona, and Alaska. The engines of the Trave,
Saale, and Aller, however, were triple-expansion, as were the Gascogne,
Bourgogne, and Champagne (their equals in speed and equipment), of the
French Compagnie Transatlantique, which were built in France. All these
steamers are of steel, with cellular bottoms carefully subdivided, and
fitted with a luxury and comfort quite unknown thirty years ago.
[Illustration: Cross-section of the Oregon.]
[Illustration: Cross-section of the Servia.]
[Illustration: Triple-expansion Engine of the Aller, Trave, and Saale.]
It was difficult, if not almost impossible, to go beyond them without
a change to twin screws. If more than the Umbria’s power was to be
developed it was safer to use it through two shafts, and the depth of
water on the New York bar is a hindrance to the use of a much greater
diameter of screw. Mr. Griscom, of Philadelphia, was the bold manager
to take the first step by laying down the Inman Company’s ships in
1887, the first of which, the City of New York, was ready for trial in
thirteen months after the signing of the contract with Messrs. James &
George Thompson, of Clydebank: a wonderful performance. The Teutonic
and Majestic quickly after took shape in the yard of Messrs. Harland &
Wolff, of Belfast, the place of birth of all of the White Star fleet.
These two lines were thus the first to accept the changed conditions,
and the City of New York and City of Paris of the former, and the
Teutonic and Majestic of the latter, still mark the high-water mark of
achievement, both as regards performance as a machine and the comfort
and luxury of the passenger. The “Cities,” as they are familiarly
termed, are 560 feet in length, by 63 feet broad, displace 13,000 tons,
and indicate over 18,000 horse-power. The two White Stars are 582 feet
long, by 57 feet 6 inches broad, of 12,000 tons displacement, and of
nearly equal horse-power with their two great competitors. In less than
twenty years these lines had thus nearly doubled the size of their
ships, and more than tripled their power.
[Illustration: Longitudinal Section of the Champagne.]
It may be of interest to the American public to know that the City
of New York and City of Paris are but two of the largest fleet under
one management on the North Atlantic. Though under one control it is
under three flags—English, Belgian, and American—our own, thanks to
the wisdom of Congress, covering but a small contingent, though our
law-makers for several years have been besieged to allow them to become
American in nationality as well as ownership. It would certainly seem
that they were quite as worthy of it as some of our importations of
another kind, but we shall probably have to wait for a little more
breadth of thought and idea under the dome at Washington before this
change can be brought about.
The building of these four ships seems to have given an impetus to the
whole of the steamship world: the Hamburg-American lines started into
new life with the Columbia, Normannia, Augusta Victoria, and Fuerst
Bismarck, twin screws of 9,500 and 10,500 displacement, which have
averaged in their best runs from New York to Southampton 19.01, 18.91,
18.31, and 19.78 knots in the order named, the distance being about
3,075 knots.
The French Company has added the twin-screw Touraine of 11,675 tons
and 18-1/2 knots sustained speed to their already splendid fleet, and
the North German Lloyds have since 1887 built the Lahn, Spree, and
Havel, all single screws; and the two last of 7,000 tons with 13,000
horse-power and a speed of 18-1/2 knots. These latter ships would
probably have been twin screws had the docks of Bremerhaven afforded
sufficient width of entrance; but whether this be the case or not,
the probability is that in the future it will be the dock which will
yield and not the ship. There is no need to make comparison of these
ships in equipment. Luxury has been carried as far as the present human
invention and imagination can take it. Suites for families are arranged
with private sitting-rooms and private tables, so that, barring the
roll so uneasy to the unhappy landsman, one could scarce know the
change from the most luxurious apartment of the Brevoort.
Such are the ships of to-day, but displacement from their eminence
is already in discussion. The builders of the City of New York are
guaranteeing a vessel to cross the Atlantic in 5 days, or at a speed
of 23-1/2 knots, the probable elements of this projected vessel being
given by _Engineering_ as a length of 630 feet and a beam of 70, with
33,000 indicated horse-power. It is a long step, but one can hardly
doubt it will soon be taken.
But that this step will be greatly aided by any material change in
the marine steam engine in the very near future is not probable,
the difficulty is now not with the engine but with the boiler;
forced draught and the higher pressures call imperatively for a new
development in the steam producer; leaky tubes and joints and a
rapid deterioration through the effort to keep up the high pressures
necessary for the successful performance of the new type of engine are
the shortcomings which must be successfully combated before we can
make another great advance. Unfortunately there is another draw-back,
for which the remedy will be even more difficult, the suffering of the
firemen induced by the greater heat of the higher pressures. Let us
hope that genius will yet invent a mechanical stoker and that we may
not of necessity subject our fellow-beings to the 140° too frequently
found in our modern fire-rooms.
We may fitly place here a tabulation of the very wonderful achievements
of the ships first mentioned, based on official data in _Engineering_
of June 19 and July 10, 1891, and covering, in the case of the
Liverpool ships, the season of 1890, except for the City of Paris,
which is for 1889. (See table on p. 45.)
The coal consumption is also officially stated by the journal from
which the above is compiled as follows: The City of New York, 328 tons:
Teutonic, 316 tons: Etruria, 330 tons. This shows an actual expenditure
of about 1.6 lb. per hour in the case of the Teutonic: slightly greater
for the City of New York, and over 1.9 for the Etruria.
But in the month of August, 1891, both the Teutonic and Majestic won
still greater laurels, the latter crossing from Queenstown to New York
in 5 days 18 hours and 8 minutes; the former in 5 days 16 hours and 31
minutes, and averaging for the run of 2,778 miles 20.35 knots per hour,
the best day’s run being 517 knots.
_Fastest Passages of the more Important Steamers between New York and
English Ports during the Season of 1890._[5]
------------------+-------------------+---------+------+-------
Name |Dimensions: |Displace-|Piston|Boiler
|Length, Breadth, |ment |Stroke|Heating
|Depth | | |Surface
------------------+-------------------+---------+------+-------
New York and | | Tons. |Feet. |Sq. Ft.
Queenstown | | | |
------------------+-------------------+---------+------+-------
City of Paris |560 × 63 × 43 | 13,000 |5 |50,265
| | | |
------------------+-------------------+---------+------+-------
City of New York |560 × 63 × 43 | 13,000 |5 |50,040
| | | |
------------------+-------------------+---------+------+-------
Majestic |582×57-1/2×59-1/8 | 12,000 |5 |40,972
------------------+-------------------+---------+------+-------
Teutonic |582×57-1/2×59-1/8 | 12,000 |5 |40,972
------------------+-------------------+---------+------+-------
Etruria |501-1/2×57.2×38.2 | 10,500 |6 |38,817
------------------+-------------------+---------+------+-------
Umbria |501-1/2×57.2×38.2 | 10,500 |6 |38,817
------------------+-------------------+---------+------+-------
City of Rome |546 × 52 × 58-3/4 | 11,230 |6 |29,286
------------------+-------------------+---------+------+-------
New York and | | | |
Southampton | | |Inches|
------------------+-------------------+---------+------+-------
Columbia |480 × 56 × 38 | 9,500 |66 |34,916
------------------+-------------------+---------+------+-------
Normannia |520 × 57-1/4 × 38 | 10,500 |66 |46,490
------------------+-------------------+---------+------+-------
Augusta Victoria |480 × 56 × 36 | 9,500 |63 |36,000
------------------+-------------------+---------+------+-------
Lahn |448 × 49 × 36-1/2 | 7,700 |72 | ...
------------------+-------------------+---------+------+-------
------------------+------------+--------+------+--------+---------
Name | Grate Area | Steam |I.H.P.|Fastest |Direction
| |Pressure| | Trip |
------------------+------------+--------+------+--------+---------
New York and |Square Feet.|Lbs. | |D. H. M.|
Queenstown | | | | |
------------------+------------+--------+------+--------+---------
City of Paris |was 1,293 |150 |18,350|5 19 18 |Westward
|now 1,026 | | | |
------------------+------------+--------+------+--------+---------
City of New York |was 1,080 |150 |18,100|5 21 19 |Westward
|now 1,096 | | | |
------------------+------------+--------+------+--------+---------
Majestic | 1,154 |180 |18,000|5 21 20 |Westward
------------------+------------+--------+------+--------+---------
Teutonic | 1,154 |180 |18,000|5 19 5 |Westward
------------------+------------+--------+------+--------+---------
Etruria | 1,606 |110 |14,300|6 6 57 |Westward
------------------+------------+--------+------+--------+---------
Umbria | 1,606 |110 |14,300|6 3 29 |Westward
------------------+------------+--------+------+--------+---------
City of Rome | 1,398 | 90 |11,890|6 22 30 |Eastward
------------------+------------+--------+------+--------+---------
New York and | | | | |
Southampton | | | | |
------------------+------------+--------+------+--------+---------
Columbia | 1,226 |150 |13,680|6 15 0 |Eastward
------------------+------------+--------+------+--------+---------
Normannia | 1,452 |160 |16,352|6 17 2 |Westward
------------------+------------+--------+------+--------+---------
Augusta Victoria | 1,120 |150 |14,110|6 22 32 |Eastward
------------------+------------+--------+------+--------+---------
Lahn | ... |150 | 9,500|7 3 0 |Eastward
------------------+------------+--------+------+--------+---------
------------------+---------+--------+-------+-------+-------
Name | Month |Distance|Average|Average|Fastest
| | | Speed | for | Day’s
| | | | Eight | Run
| | | |Months |during
| | | | |Season
------------------+---------+--------+-------+-------+-------
New York and | | Knots | Knots | Knots | Knots
Queenstown | | | | |
------------------+---------+--------+-------+-------+-------
City of Paris |August | 2,788 | 20.01 | 19.02 | 515
| | | | |
------------------+---------+--------+-------+-------+-------
City of New York |October | 2,775 | 19.64 | 19.02 | 502
| | | | |
------------------+---------+--------+-------+-------+-------
Majestic |September| 2,780 | 19.64 | 19.00 | ...
------------------+---------+--------+-------+-------+-------
Teutonic |August | 2,806 | 20.18 | 18.84 | 512
------------------+---------+--------+-------+-------+-------
Etruria |July | 2,845 | 18.80 | 18.29 | 481
------------------+---------+--------+-------+-------+-------
Umbria |August | 2,835 | 19.20 | 18.15 | 498
------------------+---------+--------+-------+-------+-------
City of Rome |Aug.-Sep.| 2,787 | 16.73 | 16.18 | 424
------------------+---------+--------+-------+-------+-------
New York and | | | | |
Southampton | | | | |
------------------+---------+--------+-------+-------+-------
Columbia |October | 3,045 | 19.15 | 18.68 | 492
------------------+---------+--------+-------+-------+-------
Normannia |August | 3,045 | 18.91 | 18.41 | 486
------------------+---------+--------+-------+-------+-------
Augusta Victoria |September| 3,049 | 18.31 | 17.52 | 470
------------------+---------+--------+-------+-------+-------
Lahn |October | ... | ... | 17.29 | ...
------------------+---------+--------+-------+-------+-------
NOTE.—The nautical mile is one-sixtieth of a degree of the Equator,
and is usually reckoned 6,080 feet, the statute mile being 5,280;
twenty nautical miles are thus about twenty-three statute miles. The
shortest distance is the arc of the great circle of the Earth passing
through the two ports; any deviation from this by varying the course
on account of intervening land or ice increases the distance to be
run.
The crown is thus for the moment with the White Star, nor is it likely
to be torn away by anything short of the tremendous effort involved in
putting afloat a new, a bigger, and a more costly ship. Owners must, of
course, count the cost of such rivalry and must put against the gain
of say sixteen hours, in order to come to the desired five days and
twenty-three knots, the cost of the thousand or twelve hundred tons
more of coal which will have to be burned, the doubled number of engine
and fire-room force, the larger crew, the interest on the greater
investment. It is a large price to pay for a gain of so small a bit of
that we generally hold so cheap—but it will be paid.
* * * * *
It has been impossible, of course, in a single chapter to do more than
touch upon the vast changes, and their causes, which have had place
in this great factor of human progress. Higher pressures and greater
expansions: condensation of the exhaust steam, and its return to the
boiler without the new admixture of sea-water, and the consequent
necessity of frequent blowing off, which comparatively but a few
years ago was so common; a better form of screw; the extensive use of
steel in machinery, by which parts have been lightened, and by the
use of which higher boiler-pressures are made possible—these are the
main steps. But in addition to steel, high pressures, and the several
other elements named which have gone to make up this progress, there
was another cause in the work chiefly done by the late W. Froude, to
be specially noticed as being that which has done more than the work
of any other man to determine the most suitable forms for ships, and
to establish the principles governing resistance. The ship-designer
has, by this work, been put upon comparatively firm ground, instead of
having a mental footing as unstable, almost, as the element in which
his ships are destined to float.