horse-car. This is not strange, for in a little over twenty years the
victorious trolley has displaced the old-time street-cars drawn by one
or two horses. Indeed, a horse-car is quite a curiosity in these modern
days, for such vehicles have almost entirely disappeared from the
streets.
The first horse railroad in the United States was completed in 1827,
and it was only seven years afterward that a small model of a circular
electric railroad was made and exhibited by Thomas Davenport, of
Brandon, Vermont. Other inventors also worked on electric railways
later on, but they did not make much progress, because in their day
there were no dynamos, and they had to use primary batteries to obtain
current. This method of generating current was far too cumbersome and
expensive for general use.
In 1879, after dynamos had become known, the firm of Siemens exhibited
at the Berlin Exhibition a road about one-third of a mile in length,
over which an electric locomotive hauled three small cars at a speed of
about eight miles an hour.
This was just before Edison had developed the efficient commercial
dynamo with low-resistance armature and high-resistance field, which
made it possible to generate and use electric power cheaply. Thus we
see that Edison was not the first to form the broad idea of a electric
railway, but his dynamo and systems of distribution and regulation of
current first made the idea commercially practicable.
When Edison made his trip to Wyoming with the astronomers in 1878 he
noticed that the farmers had to make long hauls of their grain to the
railroads or markets. He then conceived the idea of building light
electric railways to perform this service.
As we have already noted, he started on his electric-light experiments,
including the dynamo, when he returned from the West. He had not
forgotten his scheme for an electric railway, however, for, early in
1880, after the tremendous rush on the invention of the incandescent
lamp had begun to subside, he commenced the construction of a stretch
of track at Menlo Park, and at the same time began to build an electric
locomotive to operate over it.
The locomotive was an ordinary flat dump-car on a four-wheeled iron
truck. Upon this was mounted one of his dynamos, used as a motor.
It had a capacity of about twelve horse-power. Electric current was
generated by two dynamos in the machine-shop, and carried to the rails
by underground conductors.
The track was about a third of a mile in length, the rails being of
light weight and spiked to ties laid on the ground. In this short
line there were some steep grades and short curves. The locomotive
pulled three cars; one a flat freight-car; one an open awning-car,
and one box-car, facetiously called the "Pullman," with which Edison
illustrated a system of electromagnetic braking.
[Illustration: THE EDISON ELECTRIC RAILWAY AT MENLO PARK--1880]
On May 13, 1880, this road went into operation. All the laboratory
"boys" made holiday and scrambled aboard for a trip. Things went well
for a while, but presently a weakness developed and it became necessary
to return the locomotive to the shop to make changes in the mechanism.
And so it was for a short time afterward. Imperfections of one kind
and another were disclosed as the road was operated, but Edison was
equal to the occasion and overcame them, one by one. Before long he had
his locomotive running regularly, hauling the three cars with freight
and passengers back and forth over the full length of the track.
Incidentally, the writer remembers enjoying a ride over the road one
summer afternoon.
The details of the various improvements made during these months are
too many and too technical to be given here. It is a fact, however,
that at this time Edison was doing some heavy electric railway
engineering, each improvement representing a step which advanced the
art toward the perfection it has reached in these modern days.
The newspapers and technical journals lost no time in publishing
accounts of this electric railroad, and once again Menlo Park received
great numbers of visitors, including many railroad men, who came to see
and test this new method of locomotion.
Of course, in operating this early road there were a few mishaps,
fortunately none of them of a serious nature. In the correspondence of
the late Grosvenor P. Lowry, a friend and legal adviser of Mr. Edison,
is a letter dated June 5, 1880, giving an account of one experience.
The letter reads as follows: "Goddard and I have spent a part of the
day at Menlo, and all is glorious. I have ridden at forty miles an hour
on Mr. Edison's electric railway--and we ran off the track. I protested
at the rate of speed over the sharp curves, designed to show the power
of the engine, but Edison said they had done it often. Finally, when
the last trip was to be taken, I said I did not like it, but would go
along. The train jumped the track on a short curve, throwing Kruesi,
who was driving the engine, with his face down in the dirt, and another
man in a comical somersault through some underbrush. Edison was off
in a minute, jumping and laughing, and declaring it a most beautiful
accident. Kruesi got up, his face bleeding, and a good deal shaken; and
I shall never forget the expression of voice and face in which he said,
with some foreign accent: 'Oh yes! pairfeckly safe.' Fortunately no
other hurts were suffered, and in a few minutes we had the train on the
track and running again."
This first electric railway was continued in operation right along
through 1881. In the fall of that year Edison was requested by the late
Mr. Henry Villard to build a longer road at Menlo Park, equipped with
more powerful locomotives, to demonstrate the feasibility of putting
electric railroads in the Western wheat country.
Work was commenced at once, and early in 1882 the road and its
equipment were finished. It was three miles long, and had sidings,
turn-tables, freight platform and car-house. It was much more complete
and substantial than the first railroad. There were two locomotives,
one for freight and the other for passenger service.
The passenger locomotive was very speedy and hauled as many as ninety
persons at a time. Many thousands of passengers traveled over the road
during 1882. The freight locomotive was not so speedy, but could pull
heavy trains at a good speed. Taken altogether, this early electric
railway made a great advance toward modern practice as its exists
to-day.
There are many interesting stories of the railway period at Menlo Park.
One of them, as told by the late Charles T. Hughes, who worked with
Edison on the experimental roads, is as follows: "Mr. Villard sent J.
C. Henderson, one of his mechanical engineers, to see the road when
it was in operation, and we went down one day--Edison, Henderson, and
I--and went on the locomotive. Edison ran it, and just after we started
there was a trestle sixty feet long and seven feet deep, and Edison put
on all the power. When we went over it we must have been going forty
miles an hour, and I could see the perspiration come out on Henderson.
After we got over the trestle and started on down the track Henderson
said: 'When we go back I will walk. If there is any more of that kind
of running I won't be in it myself.'"
The young reader, who is now living in an age in which the electric
railway is regarded as a matter of course, will find it difficult to
comprehend that there should ever have been any doubt on the part of
engineering experts as to the practicability of electric railroads.
But in the days of which we are writing such was the case, as the
following remarks of Mr. Edison will show: "At one time Mr. Villard
got the idea that he would run the mountain division of the Northern
Pacific Railroad by electricity. He asked me if it could be done. I
said: 'Certainly; it is too easy for me to undertake; let some one else
do it.' He said: 'I want you to tackle the problem,' and he insisted on
it. So I got up a scheme of a third rail and shoe and erected it in my
yard here in Orange. When I got it all ready he had all his division
engineers come on to New York, and they came over here. I showed them
my plans, and the unanimous decision of the engineers was that it was
absolutely and utterly impracticable. That system is on the New York
Central now, and was also used on the New Haven road in its first work
with electricity."
Mr. Edison knew at the time that these engineers were wrong. They were
prejudiced and lacking in foresight, and had no faith in electric
railroading. Indeed, these particular engineers were not by any means
the only persons who could see no future for electric methods of
transportation. Their doubts were shared by capitalists and others,
and it was not until several years afterward that the business of
electrifying street railroads was commenced in real earnest.
In the mean time, however, Edison's faith did not waver, and he
continued his work on electric railways, making innumerable experiments
and taking out a great many patents, including a far-sighted one
covering a sliding contact in a slot. This principle and many of those
covered by his earlier work are in use to-day on the street railways in
large cities.
The early railroad at Menlo Park has gone to ruin and decay, but the
crude locomotive built by Edison has become the property of the Pratt
Institute, of Brooklyn, New York, to whose students it is a constant
example and incentive.
Down to the present moment Edison has kept up an active interest in
transportation problems. His latest work has been in the line of
operating street-cars with his improved storage battery. During the
time that this book has been in course of preparation he has given a
great deal of time to this question.
Some years ago there were a number of street-cars in various cities
operated by storage batteries of a class entirely different from the
battery invented by Edison. We refer to storage batteries containing
lead and sulphuric acid. These were found to be so costly to operate
and maintain that their use was abandoned.
Mr. Edison's new nickel and iron storage battery with alkaline
solution has been found by practical use to be entirely satisfactory
for operating street-cars, not only at a low cost, but also with ease
of operation and at a trifling expense for maintenance. Of course
there have been many problems, but he has surmounted the principal
difficulties, and there are now quite a number of street-cars operated
by his storage battery in various cities. These cars are earning
profits and their number is steadily increasing.
XVIII
GRINDING MOUNTAINS TO DUST
On walking along the sea-shore the reader may have noticed occasional
streaks or patches of bluish-black sand, somewhat like gunpowder in
appearance. It is carried up from the bed of the sea and deposited by
the waves on the shore to a greater or lesser extent on many beaches.
If a magnet be brought near to this "black sand" the particles will be
immediately attracted to it, just as iron filings would be in such a
case. As a matter of fact, these particles of black sand are grains of
finely divided magnetic iron in a very pure state.
Now, if we should take a piece of magnetic iron ore in the form of a
rock and grind it to powder the particles of iron could be separated
from the ground-up mass by drawing them out with a magnet, just as they
could be drawn out of a heap of seashore sand. If all the grains of
iron were thus separated and put together, or concentrated, they would
be called concentrates.
During the last century a great many experimenters besides Edison
attempted to perfect various cheap methods of magnetically separating
iron ores, but until he took up the work on a large scale no one seems
to have realized the real meaning of the tremendous problems involved.
The beginning of this work on the part of Edison was his invention
in 1880 of a peculiar form of magnetic separator. It consisted of a
suspended V-shaped hopper with an adjustable slit along the pointed
end. A long electromagnet was placed, edgewise, a little below the
hopper, and a bin with a dividing partition in the center was placed on
the floor below.
Crushed ore, or sand, was placed in the hopper. If there was no
magnetism this fine material would flow down in a straight line past
the magnet and fill the bin on one side of the partition. If, however,
the magnet were active the particles of iron would be attracted out
of the line of the falling material, but their weight would carry
them beyond the magnet and they would fall to the other side of the
partition. Thus, the material would be separated, the grains of iron
going to one side and the grains of rock or sand to the other side.
This separator, as afterward modified, was the basis of a colossal
enterprise conducted by Mr. Edison, as we shall presently relate. But
first let us glance at an early experiment on the Atlantic seashore in
1881, as mentioned by him. He says:
"Some years ago I heard one day that down at Quogue, Long Island,
there were immense deposits of black magnetic sand. This would be very
valuable if the iron could be separated from the sand. So I went down
to Quogue with one of my assistants and saw there for miles large
beds of black sand on the beach in layers from one to six inches
thick--hundreds of thousands of tons. My first thought was that it
would be a very easy matter to concentrate this, and I found I could
sell the stuff at a good price. I put up a small magnetic separating
plant, but just as I got it started a tremendous storm came up, and
every bit of that black sand went out to sea. During the twenty-eight
years that have intervened it has never come back."
In the same year a similar separating plant was put up and worked on
the Rhode Island shore by the writer under Mr. Edison's direction. More
than one thousand tons of concentrated iron ore of fine quality were
separated from sea-shore sand and sold. It was found, however, that it
could not be successfully used on account of being so finely divided.
Had this occurred a few years later, when Edison invented a system of
putting this fine ore into briquettes, that part of the story might
have been different.
Magnetic separation of ores was allowed to rest for many years after
this, so far as Edison was concerned. He was intensely busy on the
electric light, electric railway, and other similar problems until
1888, and then undertook the perfecting and manufacturing of his
improved phonograph, and other matters. Somewhere about 1890, however,
he again took up the subject of ore-separation.
For some years previous to that time the Eastern iron-mills had been
suffering because of the scarcity of low-priced high-grade ores. If
low-grade ores could be crushed and the iron therein concentrated and
sold at a reasonable price the furnaces would be benefited. Edison
decided, after mature deliberation, that if these low-grade ores
were magnetically separated on a colossal scale at a low cost the
furnace-men could be supplied with the much-desired high quality of
iron ore at a price which would be practicable.
He appreciated the fact that it was a serious and gigantic problem,
but was fully satisfied that he could solve it. He first planned a
great magnetic survey of the East, with the object of locating large
bodies of magnetic iron ore. This survey was the greatest and most
comprehensive of the kind ever made. With a peculiarly sensitive
magnetic needle to indicate the presence of magnetic ore in the earth,
he sent out men who made a survey of twenty-five miles across country,
all the way from lower Canada to North Carolina.
Edison says: "The amount of ore disclosed by this survey was simply
fabulous. How much so may be judged from the fact that in the three
thousand acres immediately surrounding the mills that I afterward
established at Edison, New Jersey, there were over two hundred million
tons of low-grade ore. I also secured sixteen thousand acres in which
the deposit was proportionately as large. These few acres alone
contained sufficient ore to supply the whole United States iron trade,
including exports, for seventy years."
Given a mountain of rock containing only one-fifth to one-fourth
magnetic iron, the broad problem confronting Edison resolved itself
into three distinct parts--first, to tear down the mountain bodily and
grind it to powder; second, to extract from this powder the particles
of iron mingled in its mass; and third, to accomplish these results at
a cost sufficiently low to give the product a commercial value.
From the start Edison realized that in order to carry out this program
there would have to be automatic and continuous treatment of the
material, and that he would have to make the fullest possible use of
natural forces, such as gravity and momentum. The carrying out of
these principles and ideas gave rise to some of the most brilliant
engineering work that has ever been done by Edison. During this period
he also made many important inventions, of which several will now be
mentioned.
As he proposed to treat enormous masses of material, one of the chief
things to be done was to provide for breaking the rock and crushing it
to powder rapidly and cheaply. After some experimenting, he found there
was no machinery to be bought that would do the work as it must be
done. He was therefore compelled to invent a series of machines for the
purpose.
The first of these was an invention quite characteristic of Edison's
daring and boldness. It embraced a gigantic piece of mechanism, called
the "Giant Rolls," which was designed to break up pieces of rock that
might be as large as an ordinary upright piano, and weighing as much as
eight tons.
A pair of iron cylinders five feet long and six feet in diameter,
covered with steel knobs, were set fifteen inches apart in a massive
frame. The rolls weighed about seventy tons. By means of a steam engine
these rolls were revolved in opposite directions until they attained
a peripheral speed of about a mile a minute. Then the rocks were
dumped into a hopper which guided them between the rolls, and in a few
seconds, with a thunderous noise, they were reduced to pieces about
the size of a man's head. The belts were released by means of slipping
friction clutches when the load was thrown on the rolls, the breaking
of the rocks being accomplished by momentum and kinetic energy.
The broken rock then passed through similar rolls of a lesser size,
by means of which it was reduced to much smaller pieces. These in
their turn passed through a series of other machines in which they
were crushed to fine powder. Here again Edison made another remarkable
invention, called the "Three-High Rolls," for reducing the rock to fine
powder. The best crushers he had been able to buy had an efficiency
of only eighteen per cent, and a loss by friction of eighty-two per
cent. By his invention he reversed these figures and obtained a working
efficiency of eighty-four per cent, and reduced the loss to sixteen per
cent.
The problems of drying and screening the broken and crushed material
were also solved most ingeniously by Edison's inventive skill and
engineering ability, and always with the idea and purpose in mind of
accomplishing these results by availing himself to the utmost of one of
the great forces of Nature--gravity.
The great extent of the concentrating works may be imagined when we
state that two hundred and fifty tons of material per hour could be
treated. Altogether, there were about four hundred and eighty immense
magnetic separators in the plant, through which this crushed rock
passed after going through the numerous crushing, drying, and screening
processes.
[Illustration: EDISON AT THE OFFICE DOOR OF THE ORE-CONCENTRATING PLANT
AT EDISON, NEW JERSEY, IN THE 'NINETIES]
If it had been necessary to transfer this tremendous quantity of
material from place to place by hand the cost would have been too
great. Edison, therefore, designed an original and ingenious system
of mechanical belt conveyors that would automatically receive and
discharge their loads at appointed places in the works, covering about
a mile in transit. They went up and down, winding in and out, turning
corners, delivering material from one bin to another, making a number
of loops in the drying-oven, filling up bins, and passing on to the
next one when full. In fact, these conveyors in automatic action seemed
to play their part with human intelligence.
We have been able to take only a passing glance at the great results
achieved by Edison in his nine years' work on this remarkable plant--a
work deserving of most serious study. The story would be incomplete,
however, if we did not mention his labors on putting the fine ore in
the form of solid briquettes.
When the separated iron was first put on the market it was found that
it could not be used in that form in the furnaces. Edison was therefore
obliged to devise some other means to make it available. After a long
series of experiments he found a way of putting it into the form of
small, solid briquettes. These answered the purpose exactly.
This called for a line of new machinery, which he had to invent to
carry out the plan. When this was completed, the great rocks went in at
one end of the works and a stream of briquettes poured out of the other
end, being made by each briquetting machine at the rate of sixty per
minute.
Thus, with never-failing persistence, infinite patience, intense
thought and hard work, Edison met and conquered, one by one, the
difficulties that had confronted him. Furnace trials of his briquettes
proved that they were even better than had been anticipated. He had
received some large orders for them and was shipping them regularly.
Everything was bright and promising, when there came a fatal blow.
The discovery of rich Bessemer ore in the Mesaba range of mountains in
Minnesota a few years before had been followed by the opening of the
mines there about this time. As this rich ore could be sold for three
dollars and fifty cents per ton, as against six dollars and fifty cents
per ton for Edison's briquettes, his great enterprise must be abandoned
at the very moment of success.
It was a sad blow to Edison's hopes. He had spent nine years of hard
work and about two millions of his own money in the great work that had
thus been brought to nought through no fault of his. The project had
lain close to his heart and ambition, indeed he had put aside almost
all other work and inventions for a while.
For five of the nine years he had lived and worked steadily at Edison
(the name of the place where the works were located), leaving there
only on Saturday night to spend Sunday at his home in Orange, and
returning to the plant by an early train on Monday morning. Life at
Edison was of the simple kind--work, meals, and a few hours' sleep day
by day, but Mr. Edison often says he never felt better than he did
during those five years.
After careful investigations and calculations it was decided to close
the plant. Mr. W. S. Mallory, his close associate during those years of
the concentrating work, says: "The plant was heavily in debt, and, as
Mr. Edison and I rode on the train to Orange, plans were discussed as
to how to make enough money to pay off the debt. Mr. Edison stated most
positively that no company with which he had been personally actively
connected had ever failed to pay its debts, and he did not propose to
have the concentrating company any exception.
"We figured carefully over the probabilities of financial returns from
the phonograph works and other enterprises, and, after discussing many
plans, it was finally decided that we would apply the knowledge we had
gained in the concentrating plant to building a plant for manufacturing
Portland cement, and that Mr. Edison would devote his attention to the
developing of a storage battery which did not use lead and sulphuric
acid.
"He started in with the maximum amount of enthusiasm and ambition,
and in the course of about three years we succeeded in paying off the
indebtedness of the concentrating works.