CHAPTER IX

At 15:42, as Rawolle named it, but at 42 minutes past 3, as Cobb

persisted in calling it, their arrangements had been completed and they

were at the front entrance to the Occidental.

At the curb stood an elegant four-seated carriage of very light

construction, with a driver upon the seat. There were no horses

attached to the vehicle, which was very low in build, and with wheels

of fair size. The driver sat in the rear, on a sort of raised single

seat, with a small wheel, like a tiller-wheel, in front of him.

It was an electric drag, with the storage batteries underneath the

seat. There were many passers-by at the time, but, thanks to Rawolle's

care, none knew who were getting into the carriage, else there would

have been a crowd in a few minutes.

Taking their seats, the driver started the current, and the carriage

rolled rapidly down toward Market street.

"What do you think of this for a carriage, Mr. Cobb?" asked Rawolle.

"It is a most decided advance upon anything we had in old days," the

other returned, looking admiringly over it. "This is, no doubt, an

electric carriage?"

"It is an electric drag, and the style of all the first-class carriages

in the city, except those which are used for hill travel. These

carriages run up grades of three hundred feet to the mile with ease."

"Are they expensive? and how long will their batteries last?"

"No; far less expensive than horses. The batteries, or accumulators,

are very small, but with great power. The weight carried by such a

carriage as this, in accumulators, is about fifteen pounds, and the

energy is the equivalent of two horses for six hours, or a greater

number of horses for a less time. The accumulators are charged at the

rate of about fifty cents per set, which is a six-hour run. The great

saving is that when the carriage is not in use, there is no expense."

The carriage was going at a good round gait, but the motion was easy

and steady.

Passing into Market street, Cobb was astonished at the magnificence of

the buildings. He could not remember ever having seen a single building

then standing as being there during his time. The architecture was

grand in the extreme; beauty was not lacking, but was combined with

strength.

He saw horses, electric motors, and cable cars, but the latter no

longer ran upon tracks on the street; the trucks were all underneath

the roadbed, while the cars were held aloft by thin but strong steel

supports. The cars, moreover, were lighter built and set closer to the

ground.

He saw no horse-cars. The pavement was everywhere of the same

material--clean, smooth, and elastic; and he rejoiced to think that at

last mankind had awakened to the fact that it was not only cruel, but

costly, to cause horses to run upon cobble-stones, and pavements of

similar construction. He did not have time to note all the many changes

which had taken place and then in view, ere the carriage stopped at the

gate of a most imposing edifice.

Alighting from his seat, Rawolle assisted him down, saying:

"Here we are, Mr. Cobb."

Having gotten out, they all went into the depot, for such Cobb was

informed it was. He was surprised at the grandeur of the building. It

far exceeded anything he had ever seen for similar purposes. Rawolle

took him around and showed him the various waiting, toilet, dining, and

other rooms.

The depot was on the site formerly occupied by the old station, at the

corner of Third and Townsend streets.

Passing into the main hall, he perceived a stream of people coming

from the left. The interior of the depot, after passing through the

main hall, was a vast space with a great arched roof. The ground was

paved with marble slabs, and divided by iron fencing into five large

compartments; the first running from side to side of the building,

while the others were set at right angles to it. Each of the four

divisions had a great slot or opening through its floor, of about two

hundred feet in length by twelve in width. The last opening was filled

by a train which had just arrived.

The people were flocking out, and through the gates into the main hall,

or, as Cobb called it, the fifth compartment.

His attention was riveted to the train as it stood upon the track. It

was so different from anything in the railway line that he had ever

seen before, that he was most anxious to learn something about it.

It was a train of five cars, each about forty feet long, and of

circular construction. It rested upon innumerable little runners, and

was set quite close to the ground. The end of each car was a huge

circular disc of a diameter a little greater than that of the car, and

having an elliptical opening of some seven feet in the long diameter.

Along each side of the cars was another set of runners, while two more

sets were upon the tops.

There were no windows to the cars, and they looked plain iron cylinders

of vast size, set upon a lot of little iron legs.

Standing there a moment, Cobb watched the last passenger leave the

hall, and soon heard the guard cry for the gates to be closed. Almost

immediately the gate of that compartment was dropped, and he saw the

huge train sink into the opening and disappear from sight.

Turning toward Rawolle, who had been watching him with a curious

expression, he exclaimed:

"Rawolle, tell me what kind of transportation is this that I have

just seen? It is something that beats my time, and I am at a loss to

understand its working."

"I do not wonder at your expression of astonishment, my dear boy;"

then pointing toward the third opening, and looking at his watch, he

continued: "You will see a similar train soon come up; watch carefully."

Cobb did as directed, and in a moment saw a train of cars, in all

respects similar to the train which he had seen disappear through the

left-hand slot, rise from below. It came up gradually, and at last

stood, as its mate had stood, flush with the floor of the room; but,

unlike the former, it had no passengers to disembark. There it stood,

silent and empty.

As the train reached the level, a placard was dropped from the top of

the gate, bearing the words "Omaha, 16 D.," in large letters.

"That is our train, Cobb," said Rawolle, following the eyes of the

other to the sign. "Let us get our traps together and get aboard."

Approaching the gate, which had by this time been thrown open, and

through which many people were passing, Rawolle showed the tickets,

and the three men passed in and proceeded along the train to the

second carriage. Curbing his impatience to learn more of his peculiar

surroundings, Cobb followed Rawolle and Lyman into the car.

The car resembled the sleepers of former years, except that it was

decorated in a grander style and had no windows. It was lighted by

electric lamps, which made it as bright as day. The seats were somewhat

differently constructed from those of the old kind, but the general

appearance of the interior was quite the same.

A porter met them at the door, and after seeing their tickets, showed

them to their section.

Throwing down his grip and coat, Rawolle said:

"Come, Cobb, there are a few minutes before the train leaves; let me

show you about."

"All right; I am at your service."

"Mr. Cobb, I think you will find this train a most decided improvement

upon those used in your day," remarked Lyman. "Of course it is old to

us, but I can imagine your surprise at many of the improvements you see

about you."

"Right you are," returned Cobb; "there are so many new and peculiar

contrivances around me that I am like a man who has just awakened

in a land of fairies. I am not going to be too curious, but await

developments, for I have no doubt that I will be satisfactorily

informed concerning them all at the proper time."

"This is the pneumatic train," continued Lyman, motioning toward the

train on the track.

"Now, hold on," interrupted Rawolle, quickly; "all in good time. It

is better to explain all this to Mr. Cobb in detail. Let him first

see what there is to be seen, and then we will explain it to him

afterward."

Passing into the first car of the train, Cobb was shown the smoker; and

here he found a hundred little inventions which had been made with a

tendency to increase the comfort of the traveler across the continent.

"This is the Central Pneumatic, or Continental Express," said Rawolle,

"excepting the baggage-cars; they are below, receiving the baggage as

it arrives."

At this moment the sound of a deep-toned gong was heard, and Rawolle

said they must hurry back, as that was the signal for the gates above

to be closed preparatory to starting.

A moment later, they were all standing on the platform between the

cars, and an instant afterward the whole train began to sink, and

soon had left the opening far above them. The train rested upon a

sort of hydraulic lift which came to rest as soon as it had reached a

level some twenty-five feet below the floor of the depot. They were

in a subterranean chamber, or rather a series of chambers, which were

brilliantly lighted by electric lamps.

There were many tracks in every direction, with moving trains upon them.

Leaning out to the side of his car, Cobb saw an engine, or what he took

to be such, move up and couple to his train, and soon he felt it being

rapidly hauled away.

This subterranean labyrinth of roads was similar to the yard of a

great railroad center. Men were in every direction, turning switches,

coupling cars, clearing tracks, etc.

Their train was taken about a mile underground, and then run into a

great iron tunnel. A peculiar sighing sound, like that of a great storm

a long distance off, now fell upon his ears. Turning inquiringly to

Rawolle, he asked the meaning of it.

"Air--sucking air," was the answer.

"Yes; I presumed as much," Cobb returned, piqued at the brevity of the

answer.

"Observe all you can, Mr. Cobb, for you have but a few minutes more. I

will explain it after we are in the car," noticing the impatience of

the other.

The tunnel in which they then were was, like the great lower chambers,

well lighted up. At one side, and opposite to where they stood, was

a recessed chamber containing what appeared to be very powerful

machinery. Cobb saw the motor disconnect from the train at this point,

but he was not permitted to notice further the working of this most

remarkable invention, for the guards ordered them into the car, and the

door was closed and bolted.

Going back to the smoker, they lighted their cigars and settled

themselves comfortably among the cushions.

"Now," exclaimed Rawolle, sending up a cloud of smoke, "now I am at

your service."

"Then, tell me all about that which I have seen," Cobb impatiently

asked. "Don't you see how anxious I am?"

"Very well. Let us commence at the beginning: In the first place, this

that you have seen is the pneumatic railway. Its official designation

is 'The Central Pneumatic.' There are, in the United States, quite

a number of these roads. From San Francisco run three, as follows:

one to the north, one to the south, and this one to the east. Here

is a map showing all these roads in the country;" and he took from

his pocket an official railway guide, and handed it to his listener.

"As the word implies, air is the motive power--not compressed, but

atmospheric pressure against a surface, on the other side of which a

partial vacuum has been created by exhaustion. This is the method in

the tunnels only. After the trains leave the great tunnels, they are

moved about the yards, which you saw were all underground, by electric

motors. Hydraulic lifts take them up to the station and lower them

again. Everything is underground until the train rises through its

opening in the floor of the depot. When the guard ordered us into

the car, and bolted the door, we had been pushed into the receiving

section of the main tunnel. The main tunnel is a complete iron and

stone structure, extending between San Francisco and Salt Lake without

break. At Salt Lake are the engines which exhaust the air from this

tunnel, the pressure of the external air being the propelling power

to move the train forward to its destination. The tunnels are twelve

feet in diameter, and the rear car of the train carries a shield, or

end-piece, which almost fills the cross-section of the tunnel; in fact,

there is but the hundredth part of an inch between the edge of the

shield and the interior side of the tunnel. The engines, as I said, are

constantly pumping out the air, but this is carried to such a degree

that the external pressure on the tubing of the tunnel is always under

one pound per square inch. A series of valves at the end of the tunnel

farthest away from the engines, permits ingress to the air which acts

against the rear end of the train to move it forward. The train is

first placed in a movable section of this tunnel, and, everything being

ready, this section is moved upon rollers into connection with the main

tunnel--a sort of valve action. The instant this is done, the air is

permitted to enter _in front_ of the train, and then gradually shut

off until, the train having acquired its normal speed, the valves are

closed altogether, and the air permitted to enter the tunnel _behind_

the train only. It is very simple, and works to perfection. There are

inlets through the rear shield of the train, to which are connected

tubes running to each car. These are the air-tubes of the train. As the

pressure of the air against the rear shield is one pound per square

inch, a like pressure is exerted at the orifice of each tube; but, as

there is no resistance to its ingress, it passes through into the

cars, causing an internal pressure of the atmosphere of nearly one

pound per square inch. Valves opening in _front_ of the rear shield,

and at a pressure of a little less than one pound per square inch,

permit of the escape of the vitiated air into the tunnel _ahead_ of the

rear shield. Thus a steady stream of pure air is maintained throughout

the whole train. The trains are received at their destination upon

compressed-air receivers, and gradually come to a stand-still. At

Salt Lake, forty five minutes are allowed for this train to transfer

passengers and for supper, and then the train starts onward for Omaha.

At that city the train is again made up and starts upon its new course

for Chicago, New York, New Orleans, Minneapolis, or other point, as

the case may be. Now, our train was placed, as I said, in an auxiliary

tunnel, which was, by simple mechanical means, brought into position

as the segment of the main tunnel. You, of course, noticed that each

car was fitted at its end with a circular disc, covering the whole end

excepting the door which leads into the next car. Well, this circular

disc covers the end car completely. When our train was brought into

the main tunnel, the pressure upon its end-section would have been, if

suddenly exerted, so great that we would have started off with a great

shock, but the air is allowed to enter behind the car gradually, as I

have explained. When the full momentum is reached the full pressure of

the external air is allowed to exert itself against the end of the

train."

"And how long does it take to gain this full momentum?" Cobb asked.

"But a few moments. Are you aware that you are now traveling at the

rate of two hundred and forty miles per hour, or four miles per minute?"

He smiled at the look of incredulity which his words evoked. Cobb was

loath to believe he was in earnest, for he felt no shock of starting,

nor did he experience any motion such as he would naturally associate

with such a terrific speed.

"Such a rate must make the wheels spin," from Cobb.

Lyman looked at him, while Rawolle burst into a laugh.

"I do not see anything to laugh at," the other retorted, a little

nettled.

"No, no, Mr. Cobb; do not be displeased. We really meant no discourtesy;

but your remark is not what you would have made had you thought a

moment, for we know you to be a man of education. We do not use wheels

on the pneumatic roads. These trains run upon the many little runners

which you saw under the cars. Were we to use wheels," he continued,

after a pause, "centrifugal force would tear them into pieces in no

time. Take the case of a wheel four feet in diameter: the circumference

of such a wheel is a little over twelve feet. At the rate of four miles

per minute, it would have to revolve 1,760 times. No wheel that can

be made would stand such a test. It would fly into fragments inside of

the first mile. A wheel of the above dimensions and at that rate of

revolution would have a centrifugal force equal to 1,000,000 pounds.

Now, as the centripetal force is the tensile strength of the material

only, and that of the best steel wire only 160,000 pounds, it will

readily be seen that the centrifugal force would instantly cause the

wheel to fly into fragments."

"You are right," Cobb answered, going over the figures in his mind.

"Wheels would never do; I can see it plainly."

"Even were we to use a smaller wheel to decrease the centrifugal force,

we would have to increase the number of revolutions, so there would be

no gain in so doing. Our trains run upon two peculiarly constructed

rails, and the runners are flanged to exactly fit the rail. There is,

in addition, on either side of the tunnel, another rail of similar

shape, while upon the upper part are two more. The car has runners

for all of these rails, and the position of them is such that the car

cannot jump the track, or swing or sway from side to side. It travels

as if in a groove, and the little runners, separate from one another,

conform to the curves of the tunnel."

"It must take powerful engines to exhaust the air from such a long

tunnel, does it not?"

"Yes, very powerful ones. But what is different from any other mode of

propulsion, the same engine can do as much service for a line 2,000

miles long as for one of 200 miles in length, rate of speed being the

same. The reason for stations at intervals of about 500 miles, is

because more trains can be kept in motion on medium short lines than on

very long ones. There are at Salt Lake, at the receiving end of this

line, fifteen engines of 5,000 horse-power each; ten at work all the

time, with five in reserve."

"A pretty strong set of engines for a single railroad, I would say; and

a costly motive power, too."

"Not so costly as you would think," he returned. "If you take into

consideration that these engines are worked by electricity, and not by

steam, and that the electricity is furnished by water-power, you will

perceive that they can be worked quite cheaply."

"Give me some of the statistics, please," said Cobb.

"Certainly. The tunnel is twelve feet in diameter, which gives it a

superficial area of 17,712 square inches. Now, at a pressure of one

pound to the square inch, a train has a pushing force at its end of

the same number of pounds. A train weighs 50,000 pounds. The heaviest

grades on the line are some of two hundred feet to the mile. The power

required to push this train up such grades is 2,000 pounds, for the

matter of friction is not taken into consideration, being, by our

arrangements, reduced to the minimum. Thus the pressure in the tunnel

is always sufficient to move eight trains. If a train moves four miles

in a minute, then the volume of air in the tunnel to be displaced is

equivalent to the area multiplied by the length, which gives 2,600,000

cubic feet; but, under a pressure of one pound, this volume becomes

3,000,000. The pumps at each station are ten in number, each of thirty

feet diameter by ten-foot stroke, with a volume for each of 7,060 cubic

feet. These pumps make thirty strokes per minute, which is equivalent

to sixty single strokes. Thus the volume of air displaced by the pumps

is 7,060 × 60 × 10 = 4,236,000 cubic feet, an amount far in excess of

that required."

"Then, judging from your remarks, there is practically no limit to the

speed which can be obtained by this method of propulsion?"

"On the contrary," Rawolle returned, "the limit is reached when the

friction on the runners generates such an amount of heat that they

begin to disintegrate. At three hundred miles per hour they become

very hot. As it is, we have to use a very peculiar kind of alloy for

runners, and during all the time of running, keep a stream of oil

flowing just in front of each runner."

"But," asked Cobb, "does not this oil congeal upon the rail in cold

weather?"

"It does, most certainly; but there are little scrapers just in front

of each runner which cut away the congealed oil to the merest fraction

of an inch from the rail. These cutters must, by the train running

between its upper and lower rails, always be just so far away, and no

farther, from the rails."

It seemed to Cobb that he could advance nothing but what this man had

a ready explanation for its action or cause. It was, indeed, a most

marvelous invention. Here he was traveling at the rate of two hundred

and forty miles per hour, and scarcely felt the motion.

"Where is the electricity for these powerful engines generated?" he

inquired.

"For the Central and Northern, as well as for the Pacific Pneumatic

and Mountain lines, the dynamos are at the Shoshone Falls, in Idaho.

These falls furnish an immense water-power, estimated at over 300,000

horse-power. The current is delivered at the station in great cables of

peculiar construction, and well insulated."

"Do you have any accidents on the roads? At such a rate of speed, an

accident would be fraught with frightful consequences," Cobb continued.

Rawolle smiled as he said:

"During your time, accidents were not uncommon--in fact, I might say

quite common, judging from the old chronicles; but we have never had an

accident yet upon any of our lines. There have been, of course, breaks

and delays; but as each train is in communication with each other,

and with each end, and with the chief of the exhausting department,

everything is known at all times regarding the position of trains and

their condition."

Striking a match, he continued:

"No train could run into the one ahead of it, for the reason that there

will always be a cushion of air between them; and further, were any

ordinary number of runners to break at one time, the train would not be

affected by the loss."

"How wonderful, yet how simple!" exclaimed Cobb, lost in admiration.

"But I am at a loss to understand why the people of my time did not

discover and put into operation the same project."

"Perhaps someone did discover the principle, but had not the means to

test his theory," Rawolle returned.

"How long has this system been in operation?"

"About thirty years," he replied, after a moment's thought.

"Tell me one other thing," said Cobb; "has the pneumatic railroad

superseded all other kinds?"

"Oh, no; by no means. There are railroads all over the United

States, and very much the same style of your day, excepting the

great improvements which have been made, and also the one other most

important fact, that all engines are run by electricity. The pneumatic

lines are through lines only, and are for rapid transit between very

distant points, and only for passengers, mail, and express. All freight

is sent by the other roads."

"Then, the towns, excepting the great centers, are connected by

electric railroads for inter-transportation?"

"Yes; the pneumatic is only an auxiliary to the rest of the roads--a

means only of overcoming great distances quickly."

"And what is considered good speed for the electric roads?"

"Seventy-five miles per hour for passenger trains, and fifty for

freights."

"Then, they must be very differently constructed from those of old,"

exclaimed Cobb.

"They have very different roadbeds, and, of course, different engines.

But enough for the present," looking at his watch. "It is 18 dial, and

we had better get into the sleeper and prepare for supper, for we are

almost at Salt Lake."

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