heavy freight service. All the engines thus far built on this plan had
been six-wheeled, some with the rear driving-axle back of the
fire-box, and others with it in front. The next step, following
logically after the adoption of the eight-wheeled "C" engine, was to
increase the size of the freight machine, and distribute the weight on
eight wheels all connected, the two rear pairs being rigid in the
frame, and the two front pairs combined into the flexible-beam truck.
This was first done in 1846, when seventeen engines on this plan were
constructed on one order for the Philadelphia and Reading Railroad
Company. Fifteen of these were of twenty tons weight, with cylinders
fifteen and a half by twenty, and wheels forty-six inches in diameter;
and two of twenty-five tons weight, with cylinders seventeen and a
quarter by eighteen, and drivers forty-two inches in diameter. These
engines were the first ones on which Mr. Baldwin placed sand-boxes,
and they were also the first built by him with roofs. On all previous
engines the footboard had only been inclosed by a railing. On these
engines for the Reading Railroad, four iron posts were carried up, and
a wooden roof supported by them. The engine-men added curtains at the
sides and front, and Mr. Baldwin on subsequent engines added sides,
with sash and glass. The cab proper, however, was of New England
origin, where the severity of the climate demanded it, and where it
had been used previous to this period.
[Illustration: Fig. 9.--BALDWIN ENGINE FOR RACK-RAIL, 1847.]
Forty-two engines were completed in 1846, and thirty-nine in 1847. The
only novelty to be noted among them was the engine "M. G. Bright,"
built for operating the inclined plane on the Madison and Indianapolis
Railroad. The rise of this incline was one in seventeen, from the bank
of the Ohio River at Madison. The engine had eight wheels, forty-two
inches in diameter, connected, and worked in the usual manner by
outside inclined cylinders, fifteen and one-half inches diameter by
twenty inches stroke. A second pair of cylinders, seventeen inches in
diameter with eighteen inches stroke of piston, was placed vertically
over the boiler, midway between the furnace and smoke-arch. The
connecting-rods worked by these cylinders connected with cranks on a
shaft under the boiler. This shaft carried a single cog-wheel at its
centre, and this cog-wheel engaged with another of about twice its
diameter on a second shaft adjacent to it and in the same plane. The
cog-wheel on this latter shaft worked in a rack-rail placed in the
centre of the track. The shaft itself had its bearings in the lower
ends of two vertical rods, one on each side of the boiler, and these
rods were united over the boiler by a horizontal bar which was
connected by means of a bent lever and connecting-rod to the piston
worked by a small horizontal cylinder placed on top of the boiler. By
means of this cylinder, the yoke carrying the shaft and cog-wheel
could be depressed and held down so as to engage the cogs with the
rack-rail, or raised out of the way when only the ordinary drivers
were required. This device was designed by Mr. Andrew Cathcart, Master
Mechanic of the Madison and Indianapolis Railroad. A similar machine,
the "John Brough," for the same plane, was built by Mr. Baldwin in
1850. The incline was worked with a rack-rail and these engines until
it was finally abandoned and a line with easy gradients substituted.
The use of iron tubes in freight engines grew in favor, and in
October, 1847, Mr. Baldwin noted that he was fitting his flues with
copper ends, "for riveting to the boiler."
The subject of burning coal continued to engage much attention, but
the use of anthracite had not as yet been generally successful. In
October, 1847, the Baltimore and Ohio Railroad Company advertised
for proposals for four engines to burn Cumberland coal, and the
order was taken and filled by Mr. Baldwin with four of his
eight-wheels-connected machines.
The year 1848 showed a falling off in business, and only twenty engines
were turned out. In the following year, however, there was a rapid
recovery, and the production of the works increased to thirty, followed
by thirty-seven in 1850, and fifty in 1851. These engines, with a few
exceptions, were confined to three patterns, the eight-wheeled
four-coupled engine, from twelve to nineteen tons in weight, for
passengers and freight, and the six- and eight-wheels-connected engine,
for freight exclusively, the six-wheeled machine weighing from twelve to
seventeen tons, and the eight-wheeled, from eighteen to twenty-seven
tons. The drivers of these six- and eight-wheels-connected machines were
made generally forty-two, with occasional variations up to forty-eight,
inches in diameter.
[Illustration: Fig. 10.--BALDWIN FAST PASSENGER ENGINE, 1848.]
The exceptions referred to in the practice of these years were the
fast passenger engines built by Mr. Baldwin during this period. Early
in 1848, the Vermont Central Railroad was approaching completion, and
Governor Paine, the President of the Company, conceived the idea that
the passenger service on the road required locomotives capable of
running at very high velocities. Henry R. Campbell, Esq., was a
contractor in building the line, and was authorized by Governor Paine
to come to Philadelphia and offer Mr. Baldwin ten thousand dollars for
a locomotive which could run with a passenger train at a speed of
sixty miles per hour. Mr. Baldwin at once undertook to meet these
conditions. The work was begun early in 1848, and in March of that
year Mr. Baldwin filed a caveat for his design. The engine was
completed in 1849, and was named the "Governor Paine." It had one pair
of driving-wheels six and a half feet in diameter, placed back of the
fire-box. Another pair of wheels, but smaller and unconnected, was
placed directly in front of the fire-box, and a four-wheeled truck
carried the front of the engine. The cylinders were seventeen and a
quarter inches diameter and twenty inches stroke, and were placed
horizontally between the frames and the boiler, at about the middle of
the waist. The connecting-rods took hold of "half-cranks" inside of
the driving-wheels. The object of placing the cylinders at the middle
of the boiler was to lessen or obviate the lateral motion of the
engine, produced when the cylinders were attached to the smoke-arch.
The bearings on the two rear axles were so contrived that, by means of
a lever, a part of the weight of the engine usually carried on the
wheels in front of the fire-box could be transferred to the
driving-axle. The "Governor Paine" was used for several years on the
Vermont Central Railroad, and then rebuilt into a four-coupled
machine. During its career, it was stated by the officers of the road
that it could be started from a state of rest and run a mile in
forty-three seconds. Three engines on the same plan, but with
cylinders fourteen by twenty, and six-feet driving-wheels, the
"Mifflin," "Blair," and "Indiana," were also built for the
Pennsylvania Railroad Company, in 1849. They weighed each about
forty-seven thousand pounds, distributed as follows: eighteen thousand
on drivers, fourteen thousand on the pair of wheels in front of the
fire-box, and fifteen thousand on the truck. By applying the lever,
the weight on the drivers could be increased to about twenty-four
thousand pounds, the weight on the wheels in front of the fire-box
being correspondingly reduced. A speed of four miles in three minutes
is recorded for them, and upon one occasion President Taylor was taken
in a special train over the road by one of these machines at a speed
of sixty miles an hour. One other engine of this pattern, the
"Susquehanna," was built for the Hudson River Railroad Company, in
1850. Its cylinders were fifteen inches diameter by twenty inches
stroke, and drivers six feet in diameter. All these engines, however,
were short-lived, and died young, of insufficient adhesion.
Eight engines with four drivers connected and half-crank-axles, were
built for the New York and Erie Railroad Company in 1849, with
seventeen by twenty inch cylinders; one-half of the number with
six-feet and the rest with five-feet drivers. These machines were
among the last on which the half-crank-axle was used. Thereafter,
outside-connected engines were constructed almost exclusively.
In May, 1848, Mr. Baldwin filed a caveat for a four-cylinder
locomotive, but never carried the design into execution. The first
instance of the use of steel axles in the practice of the
establishment occurred during the same year,--a set being placed as an
experiment under an engine constructed for the Pennsylvania Railroad
Company. In 1850, the old form of dome boiler, which had characterized
the Baldwin engine since 1834, was abandoned, and the wagon-top form
substituted.
The business in 1851 had reached the full capacity of the shop, and
the next year marked the completion of about an equal number of
engines (forty-nine). Contracts for work extended a year ahead, and,
to meet the demand, the facilities in the various departments were
increased, and resulted in the construction of sixty engines in 1853,
and sixty-two in 1854.
At the beginning of the latter year, Mr. Matthew Baird, who had been
connected with the works since 1836 as one of its foremen, entered
into partnership with Mr. Baldwin, and the style of the firm was made
M. W. Baldwin & Co.
The only novelty in the general plan of engines during this period was
the addition of the ten-wheeled engine to the patterns of the
establishment. The success of Mr. Baldwin's engines with all six or
eight wheels connected, and the two front pairs combined by the
parallel beams into a flexible truck, had been so marked that it was
natural that he should oppose any other plan for freight service. The
ten-wheeled engine, with six drivers connected, had, however, now
become a competitor. This plan of engine was first patented by
Septimus Norris, of Philadelphia, in 1846, and the original design was
apparently to produce an engine which should have equal tractive power
with the Baldwin six-wheels-connected machine. This the Norris patent
sought to accomplish by proposing an engine with six drivers
connected, and so disposed as to carry substantially the whole weight,
the forward drivers being in advance of the centre of gravity of the
engine, and the truck only serving as a guide, the front of the engine
being connected with it by a pivot-pin, but without a bearing on the
centre-plate. Mr. Norris's first engine on this plan was tried in
April, 1847, and was found not to pass curves so readily as was
expected. As the truck carried little or no weight, it would not keep
the track. The New York and Erie Railroad Company, of which John
Brandt was then Master Mechanic, shortly afterwards adopted the
ten-wheeled engine, modified in plan so as to carry a part of the
weight on the truck. Mr. Baldwin filled an order for this company, in
1850, of four eight-wheels-connected engines, and in making the
contract he agreed to substitute a truck for the front pair of wheels
if desired after trial. This, however, he was not called upon to do.
In February, 1852, Mr. J. Edgar Thomson, President of the Pennsylvania
Railroad Company, invited proposals for a number of freight
locomotives of fifty-six thousand pounds weight each. They were to be
adapted to burn bituminous coal, and to have six wheels connected and
a truck in front, which might be either of two or four wheels. Mr.
Baldwin secured the contract, and built twelve engines of the
prescribed dimensions, viz., cylinders eighteen by twenty-two; drivers
forty-four inches diameter, with chilled tires. Several of these
engines were constructed with a single pair of truck-wheels in front
of the drivers, but back of the cylinders. It was found, however,
after the engines were put in service, that the two truck-wheels
carried eighteen thousand or nineteen thousand pounds, and this was
objected to by the company as too great a weight to be carried on a
single pair of wheels. On the rest of the engines of the order,
therefore, a four-wheeled truck in front was employed.
The ten wheeled engine thereafter assumed a place in the Baldwin
classification. In 1855-56, two of twenty-seven tons weight, nineteen
by twenty-two cylinders, forty-eight inches drivers, were built for
the Portage Railroad, and three for the Pennsylvania Railroad. In
1855, '56, and '57, fourteen, of the same dimensions, were built for
the Cleveland and Pittsburg Railroad; four for the Pittsburg, Fort
Wayne and Chicago Railroad; and one for the Marietta and Cincinnati
Railroad. In 1858 and '59, one was constructed for the South Carolina
Railroad, of the same size, and six lighter ten-wheelers, with
cylinders fifteen and a half by twenty-two, and four-feet drivers, and
two with cylinders sixteen by twenty-two, and four-feet drivers, were
sent out to railroads in Cuba.
It was some years--not until after 1860, however--before this pattern
of engine wholly superseded in Mr. Baldwin's practice the old plan of
freight engine on six or eight wheels, all connected.
On three locomotives--the "Clinton," "Athens," and "Sparta"--completed
for the Central Railroad of Georgia in July, 1852, the driving-boxes
were made with a slot or cavity in the line of the vertical bearing on
the journal. The object was to produce a more uniform distribution of
the wear over the entire surface of the bearing. This was the first
instance in which this device, which has since come into general use,
was employed in the Works, and the boxes were so made by direction of
Mr. Charles Whiting, then Master Mechanic of the Central Railroad of
Georgia. He subsequently informed Mr. Baldwin that this method of
fitting up driving-boxes had been in use on the road for several years
previous to his connection with the company. As this device was
subsequently made the subject of a patent by Mr. David Matthew, these
facts may not be without interest.
In 1853, Mr. Charles Ellet, Chief Engineer of the Virginia Central
Railroad, laid a temporary track across the Blue Ridge, at Rock Fish
Gap, for use during the construction of a tunnel through the mountain.
This track was twelve thousand five hundred feet in length on the
eastern slope, ascending in that distance six hundred and ten feet, or
at the average rate of one in twenty and a half feet. The maximum
grade was calculated for two hundred and ninety-six feet per mile, and
prevailed for half a mile. It was found, however, in fact, that the
grade in places exceeded three hundred feet per mile. The shortest
radius of curvature was two hundred and thirty-eight feet. On the
western slope, which was ten thousand six hundred and fifty feet in
length, the maximum grade was two hundred and eighty feet per mile,
and the ruling radius of curvature three hundred feet. This track was
worked by two of the Baldwin six-wheels-connected flexible-beam truck
locomotives constructed in 1853-54. From a description of this track,
and the mode of working it, published by Mr. Ellet in 1856, the
following is extracted:
"The locomotives mainly relied on for this severe duty were
designed and constructed by the firm of M. W. Baldwin & Company,
of Philadelphia. The slight modifications introduced at the
instance of the writer to adapt them better to the particular
service to be performed in crossing the Blue Ridge, did not touch
the working proportions or principle of the engines, the merits
of which are due to the patentee, M. W. Baldwin, Esq.
"These engines are mounted on six wheels, all of which are
drivers, and coupled, and forty-two inches diameter. The wheels
are set very close, so that the distance between the extreme
points of contact of the wheels and the rail, of the front and
rear drivers, is nine feet four inches. This closeness of the
wheels, of course, greatly reduces the difficulty of turning the
short curves of the road. The diameter of the cylinders is
sixteen and a half inches, and the length of the stroke twenty
inches. To increase the adhesion, and at the same time avoid the
resistance of a tender, the engine carries its tank upon the
boiler, and the footboard is lengthened out and provided with
suspended side-boxes, where a supply of fuel may be stored. By
this means the weight of wood and water, instead of abstracting
from the effective power of the engine, contributes to its
adhesion and consequent ability to climb the mountain. The total
weight of these engines is fifty-five thousand pounds, or
twenty-seven and a half tons, when the boiler and tank are
supplied with water, and fuel enough for a trip of eight miles is
on board. The capacity of the tank is sufficient to hold one
hundred cubic feet of water, and it has storage-room on top for
one hundred cubic feet of wood, in addition to what may be
carried in the side-boxes and on the footboard.
"To enable the engines better to adapt themselves to the flexures
of the road, the front and middle pairs of drivers are held in
position by wrought-iron beams, having cylindrical boxes in each
end for the journal-bearings, which beams vibrate on spherical
pins fixed in the frame of the engine on each side, and resting
on the centres of the beams. The object of this arrangement is to
form a truck, somewhat flexible, which enables the drivers more
readily to traverse the curves of the road.
"The writer has never permitted the power of the engines on this
mountain road to be fully tested. The object has been to work the
line regularly, economically, and, above all, _safely_; and these
conditions are incompatible with experimental loads subjecting
the machinery to severe strains. The regular daily service of
each of the engines is to make four trips, of eight miles, over
the mountain, drawing one eight-wheel baggage car, together with
two eight-wheel passenger cars, in each direction.
"In conveying freight, the regular train on the mountain is three
of the eight-wheel house-cars, fully loaded, or four of them when
empty or partly loaded.
"These three cars, when full, weigh, with their loads, from forty
to forty-three tons. Sometimes, though rarely, when the business
has been unusually heavy, the loads have exceeded fifty tons.
"With such trains the engines are stopped on the track, ascending
or descending, and are started again, on the steepest grades, at
the discretion of the engineer.
"Water, for the supply of the engines, has been found difficult
to obtain on the mountain; and, since the road was constructed, a
tank has been established on the eastern slope, where the
ascending engines stop daily on a grade of two hundred and eighty
feet per mile, and are there held by the brakes while the tank is
being filled, and started again at the signal and without any
difficulty.
"The ordinary speed of the engines, when loaded, is seven and a
half miles an hour on the ascending grades, and from five and a
half to six miles an hour on the descent.
"When the road was first opened, it speedily appeared that the
difference of forty-three feet on the western side, and
fifty-eight feet on the eastern side, between the grades on
curves of three hundred feet radii and those on straight lines,
was not sufficient to compensate for the increased traction due
to such curvature. The velocity, with a constant supply of steam,
was promptly retarded on passing from a straight line to a curve,
and promptly accelerated again on passing from the curve to the
straight line. But, after a little experience in the working of
the road, it was found advisable to supply a small amount of
grease to the flange of the engine by means of a sponge,
saturated with oil, which, when needed, is kept in contact with
the wheel by a spring. Since the use of the oil was introduced,
the difficulty of turning the curves has been so far diminished,
that it is no longer possible to determine whether grades of two
hundred and thirty-seven and six-tenths feet per mile on curves
of three hundred feet radius, or grades of two hundred and
ninety-six feet per mile on straight lines, are traversed most
rapidly by the engine.
"When the track is in good condition, the brakes of only two of
the cars possess sufficient power to control and regulate the
movement of the train,--that is to say, they will hold back the
two cars and the engine. When there are three or more cars in the
train, the brakes on the cars, of course, command the train so
much the more easily.
"But the safety of the train is not dependent on the brakes of
the cars. There is also a valve or air-cock in the steam-chest,
under the control of the engineer. This air-cock forms an
independent brake, exclusively at the command of the engineer,
and which can always be applied when the engine itself is in
working order. The action of this power may be made ever so
gradual, either slightly relieving the duty of the brakes on the
cars, or bringing into play the entire power of the engine. The
train is thus held in complete command."
The Mountain Top Track, it may be added, was worked successfully for
several years, by the engines described in the above extract, until it
was abandoned on the completion of the tunnel. The exceptionally steep
grades and short curves which characterized the line, afforded a
complete and satisfactory test of the adaptation of these machines to
such peculiar service.
But the period now under consideration was marked by another, and a
most important, step in the progress of American locomotive practice.
We refer to the introduction of the link-motion. Although this device
was first employed by William T. James, of New York, in 1832, and
eleven years later by the Stephensons, in England, and was by them
applied thenceforward on their engines, it was not until 1849 that it
was adopted in this country. In that year Mr. Thomas Rogers, of the
Rogers Locomotive and Machine Company, introduced it in his practice.
Other builders, however, strenuously resisted the innovation, and none
more so than Mr. Baldwin. The theoretical objections which confessedly
apply to the device, but which practically have been proved to be
unimportant, were urged from the first by Mr. Baldwin as arguments
against its use. The strong claim of the advocates of the link-motion,
that it gave a means of cutting off steam at any point of the stroke,
could not be gainsaid, and this was admitted to be a consideration of
the first importance. This very circumstance undoubtedly turned Mr.
Baldwin's attention to the subject of methods for cutting off steam,
and one of the first results was his "Variable Cut-off," patented
April 27, 1852. This device consisted of two valves, the upper sliding
upon the lower, and worked by an eccentric and rock-shaft in the usual
manner. The lower valve fitted steam-tight to the sides of the
steam-chest and the under surface of the upper valve. When the piston
reached each end of its stroke, the full pressure of steam from the
boiler was admitted around the upper valve, and transferred the lower
valve instantaneously from one end of the steam-chest to the other.
The openings through the two valves were so arranged that steam was
admitted to the cylinder only for a part of the stroke. The effect
was, therefore, to cut off steam at a given point, and to open the
induction and exhaust ports substantially at the same instant and to
their full extent. The exhaust port, in addition, remained fully open
while the induction port was gradually closing, and after it had
entirely closed. Although this device was never put in use, it may be
noted in passing that it contained substantially the principle of the
steam-pump, as since patented and constructed.
Early in 1853, Mr. Baldwin abandoned the half-stroke cut-off,
previously described, and which he had been using since 1845, and
adopted the variable cut-off, which was already employed by other
builders. One of his letters, written in January, 1853, states his
position, as follows:
"I shall put on an improvement in the shape of a variable
cut-off, which can be operated by the engineer while the machine
is running, and which will cut off anywhere from six to twelve
inches, according to the load and amount of steam wanted, and
this without the link-motion, which I could never be entirely
satisfied with. I still have the independent cut-off, and the
additional machinery to make it variable will be simple and not
liable to be deranged."