Edison, His Life and Inventions
by
Frank Lewis Dyer and Thomas Commerford Martin
Part 8 out of 17
is it from here to Lawrence; it is a long walk, isn't it?'
`Yes, rather.' He said: `Of course you will understand
I meant without oil.' To say I was deeply perplexed
does not express my feelings. We were at
the machine works, Goerck Street. I started for the
oil-room, when, about entering, I saw a small funnel
lying on the floor. It had been stepped on and
flattened. I took it up, and it had solved the engine-
oiling problem--and my walk to Lawrence like a
tramp actor's was off! The eccentric strap had a round
glass oil-cup with a brass base that screwed into the
strap. I took it off, and making a sketch, went to
Dave Cunningham, having the funnel in my hand to
illustrate what I wanted made. I requested him to
make a sheet-brass oil-cup and solder it to the base
I had. He did so. I then had a standard made to
hold another oil-cup, so as to see and regulate the
drop-feed. On this combination I obtained a patent
which is now universally used."
It is needless to say that in due course the engine
builders of the United States developed a variety of
excellent prime movers for electric-light and power
plants, and were grateful to the art from which such
a stimulus came to their industry; but for many
years one never saw an Edison installation without
expecting to find one or more Armington & Sims high-
speed engines part of it. Though the type has gone
out of existence, like so many other things that are
useful in their day and generation, it was once a very
vital part of the art, and one more illustration of that
intimate manner in which the advances in different
fields of progress interact and co-operate.
Edison had installed his historic first great central-
station system in New York on the multiple arc system
covered by his feeder and main invention, which
resulted in a notable saving in the cost of conductors
as against a straight two-wire system throughout of
the "tree" kind. He soon foresaw that still greater
economy would be necessary for commercial success
not alone for the larger territory opening, but for the
compact districts of large cities. Being firmly convinced
that there was a way out, he pushed aside a
mass of other work, and settled down to this problem,
with the result that on November 20, 1882, only two
months after current had been sent out from Pearl
Street, he executed an application for a patent covering
what is now known as the "three-wire system."
It has been universally recognized as one of the most
valuable inventions in the history of the lighting art.[13]
Its use resulted in a saving of over 60 per cent. of copper
in conductors, figured on the most favorable basis
previously known, inclusive of those calculated under
his own feeder and main system. Such economy of
outlay being effected in one of the heaviest items of
expense in central-station construction, it was now
made possible to establish plants in towns where the
large investment would otherwise have been quite
prohibitive. The invention is in universal use today,
alike for direct and for alternating current, and
as well in the equipment of large buildings as in the
distribution system of the most extensive central-station
networks. One cannot imagine the art without it.
[13] For technical description and illustration of this invention,
see Appendix.
The strong position held by the Edison system,
under the strenuous competition that was already
springing up, was enormously improved by the
introduction of the three-wire system; and it gave an
immediate impetus to incandescent lighting. Desiring
to put this new system into practical use promptly,
and receiving applications for licenses from all
over the country, Edison selected Brockton,
Massachusetts, and Sunbury, Pennsylvania, as the two
towns for the trial. Of these two Brockton required
the larger plant, but with the conductors placed
underground. It was the first to complete its arrangements
and close its contract. Mr. Henry Villard, it
will be remembered, had married the daughter of
Garrison, the famous abolitionist, and it was through
his relationship with the Garrison family that Brockton
came to have the honor of exemplifying so soon
the principles of an entirely new art. Sunbury, however,
was a much smaller installation, employed overhead
conductors, and hence was the first to "cross the
tape." It was specially suited for a trial plant also,
in the early days when a yield of six or eight lamps
to the horse-power was considered subject for
congratulation. The town being situated in the coal
region of Pennsylvania, good coal could then be
obtained there at seventy-five cents a ton.
The Sunbury generating plant consisted of an
Armington & Sims engine driving two small Edison
dynamos having a total capacity of about four hundred
lamps of 16 c.p. The indicating instruments
were of the crudest construction, consisting of two
voltmeters connected by "pressure wires" to the
centre of electrical distribution. One ammeter, for
measuring the quantity of current output, was interpolated
in the "neutral bus" or third-wire return
circuit to indicate when the load on the two machines
was out of balance. The circuits were opened and
closed by means of about half a dozen roughly made
plug-switches.[14] The "bus-bars" to receive the
current from the dynamos were made of No. 000 copper
line wire, straightened out and fastened to the wooden
sheathing of the station by iron staples without any
presence to insulation. Commenting upon this Mr.
W. S. Andrews, detailed from the central staff, says:
"The interior winding of the Sunbury station, including
the running of two three-wire feeders the entire
length of the building from back to front, the wiring
up of the dynamos and switchboard and all instruments,
together with bus-bars, etc.--in fact, all
labor and material used in the electrical wiring
installation--amounted to the sum of $90. I received
a rather sharp letter from the New York office
expostulating for this EXTRAVAGANT EXPENDITURE, and
stating that great economy must be observed in future!"
The street conductors were of the overhead pole-line
construction, and were installed by the construction
company that had been organized by Edison to build
and equip central stations. A special type of street
pole had been devised by him for the three-wire system.
[14] By reason of the experience gained at this station through
the use of these crude plug-switches, Mr. Edison started a competition
among a few of his assistants to devise something better.
The result was the invention of a "breakdown" switch by Mr.
W. S. Andrews, which was accepted by Mr. Edison as the best of
the devices suggested, and was developed and used for a great
many years afterward.
Supplementing the story of Mr. Andrews is that of
Lieut. F. J. Sprague, who also gives a curious glimpse
of the glorious uncertainties and vicissitudes of that
formative period. Mr. Sprague served on the jury at
the Crystal Palace Exhibition with Darwin's son--
the present Sir Horace--and after the tests were
ended left the Navy and entered Edison's service at
the suggestion of Mr. E. H. Johnson, who was Edison's
shrewd recruiting sergeant in those days: "I resigned
sooner than Johnson expected, and he had
me on his hands. Meanwhile he had called upon me
to make a report of the three-wire system, known in
England as the Hopkinson, both Dr. John Hopkinson
and Mr. Edison being independent inventors at
practically the same time. I reported on that, left
London, and landed in New York on the day of the
opening of the Brooklyn Bridge in 1883--May 24--
with a year's leave of absence.
"I reported at the office of Mr. Edison on Fifth
Avenue and told him I had seen Johnson. He looked
me over and said: `What did he promise you?' I
replied: `Twenty-five hundred dollars a year.' He
did not say much, but looked it. About that time
Mr. Andrews and I came together. On July 2d of that
year we were ordered to Sunbury, and to be ready to
start the station on the fourth. The electrical work
had to be done in forty-eight hours! Having travelled
around the world, I had cultivated an indifference
to any special difficulties of that kind. Mr.
Andrews and I worked in collaboration until the
night of the third. I think he was perhaps more
appreciative than I was of the discipline of the Edison
Construction Department, and thought it would be
well for us to wait until the morning of the fourth
before we started up. I said we were sent over to
get going, and insisted on starting up on the night
of the third. We had an Armington & Sims engine
with sight-feed oiler. I had never seen one, and did
not know how it worked, with the result that we soon
burned up the babbitt metal in the bearings and spent
a good part of the night getting them in order. The
next day Mr. Edison, Mr. Insull, and the chief
engineer of the construction department appeared on
the scene and wanted to know what had happened.
They found an engine somewhat loose in the bearings,
and there followed remarks which would not look
well in print. Andrews skipped from under; he
obeyed orders; I did not. But the plant ran, and it
was the first three-wire station in this country."
Seen from yet another angle, the worries of this
early work were not merely those of the men on the
"firing line." Mr. Insull, in speaking of this period,
says: "When it was found difficult to push the central-
station business owing to the lack of confidence
in its financial success, Edison decided to go into the
business of promoting and constructing central-station
plants, and he formed what was known as the
Thomas A. Edison Construction Department, which
he put me in charge of. The organization was crude,
the steam-engineering talent poor, and owing to the
impossibility of getting any considerable capital
subscribed, the plants were put in as cheaply as
possible. I believe that this construction department
was unkindly named the `Destruction Department.'
It served its purpose; never made any money; and I
had the unpleasant task of presiding at its obsequies."
On July 4th the Sunbury plant was put into commercial
operation by Edison, and he remained a week
studying its conditions and watching for any unforeseen
difficulty that might arise. Nothing happened,
however, to interfere with the successful running of
the station, and for twenty years thereafter the same
two dynamos continued to furnish light in Sunbury.
They were later used as reserve machines, and finally,
with the engine, retired from service as part of
the "Collection of Edisonia"; but they remain in
practically as good condition as when installed in
1883.
Sunbury was also provided with the first electro-
chemical meters used in the United States outside
New York City, so that it served also to accentuate
electrical practice in a most vital respect--namely,
the measurement of the electrical energy supplied to
customers. At this time and long after, all arc
lighting was done on a "flat rate" basis. The arc
lamp installed outside a customer's premises, or in
a circuit for public street lighting, burned so many
hours nightly, so many nights in the month; and was
paid for at that rate, subject to rebate for hours
when the lamp might be out through accident. The
early arc lamps were rated to require 9 to 10 amperes
of current, at 45 volts pressure each, receiving which
they were estimated to give 2000 c.p., which was arrived
at by adding together the light found at four
different positions, so that in reality the actual light
was about 500 c.p. Few of these data were ever
actually used, however; and it was all more or less a
matter of guesswork, although the central-station
manager, aiming to give good service, would naturally
see that the dynamos were so operated as to maintain
as steadily as possible the normal potential and current.
The same loose methods applied to the early
attempts to use electric motors on arc-lighting circuits,
and contracts were made based on the size of
the motor, the width of the connecting belt, or the
amount of power the customer thought he used--
never on the measurement of the electrical energy
furnished him.
Here again Edison laid the foundation of standard
practice. It is true that even down to the present
time the flat rate is applied to a great deal of
incandescent lighting, each lamp being charged for
individually according to its probable consumption
during each month. This may answer, perhaps, in a
small place where the manager can gauge pretty
closely from actual observation what each customer
does; but even then there are elements of risk and
waste; and obviously in a large city such a method
would soon be likely to result in financial disaster to
the plant. Edison held that the electricity sold must
be measured just like gas or water, and he proceeded
to develop a meter. There was infinite scepticism
around him on the subject, and while other inventors
were also giving the subject their thought, the public
took it for granted that anything so utterly intangible
as electricity, that could not be seen or weighed, and
only gave secondary evidence of itself at the exact
point of use, could not be brought to accurate regis-
tration. The general attitude of doubt was exemplified
by the incident in Mr. J. P. Morgan's office,
noted in the last chapter. Edison, however, had
satisfied himself that there were various ways of
accomplishing the task, and had determined that the
current should be measured on the premises of every
consumer. His electrolytic meter was very successful,
and was of widespread use in America and in Europe
until the perfection of mechanical meters by Elihu
Thomson and others brought that type into general
acceptance. Hence the Edison electrolytic meter is
no longer used, despite its excellent qualities. Houston
& Kennelly in their Electricity in Everyday Life
sum the matter up as follows: "The Edison chemical
meter is capable of giving fair measurements of the
amount of current passing. By reason, however, of
dissatisfaction caused from the inability of customers
to read the indications of the meter, it has in later
years, to a great extent, been replaced by registering
meters that can be read by the customer."
The principle employed in the Edison electrolytic
meter is that which exemplifies the power of electricity
to decompose a chemical substance. In other
words it is a deposition bath, consisting of a glass cell
in which two plates of chemically pure zinc are dipped
in a solution of zinc sulphate. When the lights or
motors in the circuit are turned on, and a certain
definite small portion of the current is diverted to
flow through the meter, from the positive plate to the
negative plate, the latter increases in weight by receiving
a deposit of metallic zinc; the positive plate
meantime losing in weight by the metal thus carried
away from it. This difference in weight is a very
exact measure of the quantity of electricity, or number
of ampere-hours, that have, so to speak, passed
through the cell, and hence of the whole consumption
in the circuit. The amount thus due from the customer
is ascertained by removing the cell, washing
and drying the plates, and weighing them in a chemical
balance. Associated with this simple form of
apparatus were various ingenious details and refinements
to secure regularity of operation, freedom from
inaccuracy, and immunity from such tampering as
would permit theft of current or damage. As the
freezing of the zinc sulphate solution in cold weather
would check its operation, Edison introduced, for
example, into the meter an incandescent lamp and
a thermostat so arranged that when the temperature
fell to a certain point, or rose above another point, it
was cut in or out; and in this manner the meter
could be kept from freezing. The standard Edison
meter practice was to remove the cells once a month
to the meter-room of the central-station company
for examination, another set being substituted. The
meter was cheap to manufacture and install, and not
at all liable to get out of order.
In December, 1888, Mr. W. J. Jenks read an interesting
paper before the American Institute of Electrical
Engineers on the six years of practical experience
had up to that time with the meter, then more generally
in use than any other. It appears from the
paper that twenty-three Edison stations were then
equipped with 5187 meters, which were relied upon
for billing the monthly current consumption of
87,856 lamps and 350 motors of 1000 horse-power
total. This represented about 75 per cent. of the
entire lamp capacity of the stations. There was an
average cost per lamp for meter operation of twenty-
two cents a year, and each meter took care of an
average of seventeen lamps. It is worthy of note,
as to the promptness with which the Edison stations
became paying properties, that four of the metered
stations were earning upward of 15 per cent. on their
capital stock; three others between 8 and 10 per cent.;
eight between 5 and 8 per cent.; the others having
been in operation too short a time to show definite
results, although they also went quickly to a dividend
basis. Reports made in the discussion at the meeting
by engineers showed the simplicity and success
of the meter. Mr. C. L. Edgar, of the Boston Edison
system, stated that he had 800 of the meters in service
cared for by two men and three boys, the latter
employed in collecting the meter cells; the total cost
being perhaps $2500 a year. Mr. J. W. Lieb wrote
from Milan, Italy, that he had in use on the Edison
system there 360 meters ranging from 350 ampere-
hours per month up to 30,000.
In this connection it should be mentioned that
the Association of Edison Illuminating Companies
in the same year adopted resolutions unanimously to
the effect that the Edison meter was accurate, and
that its use was not expensive for stations above
one thousand lights; and that the best financial
results were invariably secured in a station selling
current by meter. Before the same association, at
its meeting in September, 1898, at Sault Ste. Marie,
Mr. C. S. Shepard read a paper on the meter practice
of the New York Edison Company, giving data as to
the large number of Edison meters in use and the
transition to other types, of which to-day the company
has several on its circuits: "Until October,
1896, the New York Edison Company metered its
current in consumer's premises exclusively by the
old-style chemical meters, of which there were
connected on that date 8109. It was then determined
to purchase no more." Mr. Shepard went on to
state that the chemical meters were gradually displaced,
and that on September 1, 1898, there were on
the system 5619 mechanical and 4874 chemical. The
meter continued in general service during 1899, and
probably up to the close of the century.
Mr. Andrews relates a rather humorous meter story
of those early days: "The meter man at Sunbury was
a firm and enthusiastic believer in the correctness of
the Edison meter, having personally verified its reading
many times by actual comparison of lamp-hours.
One day, on making out a customer's bill, his confidence
received a severe shock, for the meter reading
showed a consumption calling for a charge of over
$200, whereas he knew that the light actually used
should not cost more than one-quarter of that amount.
He weighed and reweighed the meter plates, and pursued
every line of investigation imaginable, but all
in vain. He felt he was up against it, and that perhaps
another kind of a job would suit him better.
Once again he went to the customer's meter to look
around, when a small piece of thick wire on the floor
caught his eye. The problem was solved. He sud-
denly remembered that after weighing the plates he
went and put them in the customer's meter; but the
wire attached to one of the plates was too long to
go in the meter, and he had cut it off. He picked up
the piece of wire, took it to the station, weighed it
carefully, and found that it accounted for about $150
worth of electricity, which was the amount of the
difference."
Edison himself is, however, the best repertory of
stories when it comes to the difficulties of that early
period, in connection with metering the current and
charging for it. He may be quoted at length as
follows: "When we started the station at Pearl
Street, in September, 1882, we were not very
commercial. We put many customers on, but did not
make out many bills. We were more interested in
the technical condition of the station than in the
commercial part. We had meters in which there
were two bottles of liquid. To prevent these electrolytes
from freezing we had in each meter a strip
of metal. When it got very cold the metal would
contract and close a circuit, and throw a lamp into
circuit inside the meter. The heat from this lamp
would prevent the liquid from freezing, so that the
meter could go on doing its duty. The first cold day
after starting the station, people began to come in
from their offices, especially down in Front Street
and Water Street, saying the meter was on fire. We
received numerous telephone messages about it.
Some had poured water on it, and others said: `Send
a man right up to put it out.'
"After the station had been running several months
and was technically a success, we began to look after
the financial part. We started to collect some bills;
but we found that our books were kept badly, and
that the person in charge, who was no business man,
had neglected that part of it. In fact, he did not
know anything about the station, anyway. So I got
the directors to permit me to hire a man to run the
station. This was Mr. Chinnock, who was then
superintendent of the Metropolitan Telephone Company
of New York. I knew Chinnock to be square and of
good business ability, and induced him to leave his
job. I made him a personal guarantee, that if he
would take hold of the station and put it on a
commercial basis, and pay 5 per cent. on $600,000, I
would give him $10,000 out of my own pocket. He
took hold, performed the feat, and I paid him the
$10,000. I might remark in this connection that
years afterward I applied to the Edison Electric
Light Company asking them if they would not like
to pay me this money, as it was spent when I was
very hard up and made the company a success, and
was the foundation of their present prosperity. They
said they `were sorry'--that is, `Wall Street sorry'--
and refused to pay it. This shows what a nice, genial,
generous lot of people they have over in Wall Street.
"Chinnock had a great deal of trouble getting the
customers straightened out. I remember one man
who had a saloon on Nassau Street. He had had his
lights burning for two or three months. It was in
June, and Chinnock put in a bill for $20; July for
$20; August about $28; September about $35. Of
course the nights were getting longer. October about
$40; November about $45. Then the man called
Chinnock up. He said: `I want to see you about
my electric-light bill.' Chinnock went up to see him.
He said: `Are you the manager of this electric-light
plant?' Chinnock said: `I have the honor.' `Well,'
he said, my bill has gone from $20 up to $28, $35,
$45. I want you to understand, young fellow, that
my limit is $60.'
"After Chinnock had had all this trouble due to
the incompetency of the previous superintendent, a
man came in and said to him: `Did Mr. Blank have
charge of this station?' `Yes.' `Did he know anything
about running a station like this?' Chinnock
said: `Does he KNOW anything about running a station
like this? No, sir. He doesn't even suspect anything.'
"One day Chinnock came to me and said: `I have
a new customer.' I said: `What is it?' He said:
`I have a fellow who is going to take two hundred
and fifty lights.' I said: `What for?' `He has a
place down here in a top loft, and has got two hundred
and fifty barrels of "rotgut" whiskey. He puts a
light down in the barrel and lights it up, and it ages
the whiskey.' I met Chinnock several weeks after,
and said: `How is the whiskey man getting along?'
`It's all right; he is paying his bill. It fixes the
whiskey and takes the shudder right out of it.' Somebody
went and took out a patent on this idea later.
"In the second year we put the Stock Exchange on
the circuits of the station, but were very fearful that
there would be a combination of heavy demand and
a dark day, and that there would be an overloaded
station. We had an index like a steam-gauge, called
an ampere-meter, to indicate the amount of current
going out. I was up at 65 Fifth Avenue one afternoon.
A sudden black cloud came up, and I telephoned
to Chinnock and asked him about the load.
He said: `We are up to the muzzle, and everything is
running all right.' By-and-by it became so thick we
could not see across the street. I telephoned again,
and felt something would happen, but fortunately it
did not. I said to Chinnock: `How is it now?' He
replied: `Everything is red-hot, and the ampere-
meter has made seventeen revolutions.' "
In 1883 no such fittings as "fixture insulators" were
known. It was the common practice to twine the
electric wires around the disused gas-fixtures, fasten
them with tape or string, and connect them to lamp-
sockets screwed into attachments under the gas-
burners--elaborated later into what was known as
the "combination fixture." As a result it was no
uncommon thing to see bright sparks snapping between
the chandelier and the lighting wires during
a sharp thunder-storm. A startling manifestation of
this kind happened at Sunbury, when the vivid display
drove nervous guests of the hotel out into the
street, and the providential storm led Mr. Luther
Stieringer to invent the "insulating joint." This
separated the two lighting systems thoroughly, went into
immediate service, and is universally used to-day.
Returning to the more specific subject of pioneer
plants of importance, that at Brockton must be considered
for a moment, chiefly for the reason that the
city was the first in the world to possess an Edison
station distributing current through an underground
three-wire network of conductors--the essentially
modern contemporaneous practice, standard twenty-
five years later. It was proposed to employ pole-line
construction with overhead wires, and a party of
Edison engineers drove about the town in an open
barouche with a blue-print of the circuits and streets
spread out on their knees, to determine how much
tree-trimming would be necessary. When they came
to some heavily shaded spots, the fine trees were
marked "T" to indicate that the work in getting
through them would be "tough." Where the trees
were sparse and the foliage was thin, the same cheerful
band of vandals marked the spots "E" to indicate
that there it would be "easy" to run the wires. In
those days public opinion was not so alive as now
to the desirability of preserving shade-trees, and of
enhancing the beauty of a city instead of destroying it.
Brockton had a good deal of pride in its fine trees,
and a strong sentiment was very soon aroused against
the mutilation proposed so thoughtlessly. The investors
in the enterprise were ready and anxious to
meet the extra cost of putting the wires underground.
Edison's own wishes were altogether for the use of
the methods he had so carefully devised; and hence
that bustling home of shoe manufacture was spared
this infliction of more overhead wires.
The station equipment at Brockton consisted at
first of three dynamos, one of which was so arranged
as to supply both sides of the system during light
loads by a breakdown switch connection. This
arrangement interfered with correct meter registra-
tion, as the meters on one side of the system registered
backward during the hours in which the combination
was employed. Hence, after supplying an all-night
customer whose lamps were on one side of the circuits,
the company might be found to owe him some
thing substantial in the morning. Soon after the
station went into operation this ingenious plan was
changed, and the third dynamo was replaced by two
others. The Edison construction department took
entire charge of the installation of the plant, and the
formal opening was attended on October 1, 1883, by
Mr. Edison, who then remained a week in ceaseless
study and consultation over the conditions developed
by this initial three-wire underground plant. Some
idea of the confidence inspired by the fame of Edison
at this period is shown by the fact that the first
theatre ever lighted from a central station by
incandescent lamps was designed this year, and opened in
1884 at Brockton with an equipment of three hundred
lamps. The theatre was never piped for gas! It was
also from the Brockton central station that current
was first supplied to a fire-engine house--another
display of remarkably early belief in the trustworthiness
of the service, under conditions where continuity
of lighting was vital. The building was equipped in
such a manner that the striking of the fire-alarm
would light every lamp in the house automatically
and liberate the horses. It was at this central station
that Lieutenant Sprague began his historic work on
the electric motor; and here that another distinguished
engineer and inventor, Mr. H. Ward Leonard,
installed the meters and became meter man, in order
that he might study in every intimate detail the
improvements and refinements necessary in that branch
of the industry.
The authors are indebted for these facts and some
other data embodied in this book to Mr. W. J. Jenks,
who as manager of this plant here made his debut in
the Edison ranks. He had been connected with local
telephone interests, but resigned to take active charge
of this plant, imbibing quickly the traditional Edison
spirit, working hard all day and sleeping in the station
at night on a cot brought there for that purpose. It
was a time of uninterrupted watchfulness. The difficulty
of obtaining engineers in those days to run the
high-speed engines (three hundred and fifty revolutions
per minute) is well illustrated by an amusing
incident in the very early history of the station. A
locomotive engineer had been engaged, as it was supposed
he would not be afraid of anything. One evening
there came a sudden flash of fire and a spluttering,
sizzling noise. There had been a short-circuit on
the copper mains in the station. The fireman hid
behind the boiler and the engineer jumped out of the
window. Mr. Sprague realized the trouble, quickly
threw off the current and stopped the engine.
Mr. Jenks relates another humorous incident in
connection with this plant: "One night I heard a
knock at the office door, and on opening it saw two
well-dressed ladies, who asked if they might be shown
through. I invited them in, taking them first to the
boiler-room, where I showed them the coal-pile, explaining
that this was used to generate steam in the
boiler. We then went to the dynamo-room, where
I pointed out the machines converting the steam-
power into electricity, appearing later in the form of
light in the lamps. After that they were shown the
meters by which the consumption of current was
measured. They appeared to be interested, and I
proceeded to enter upon a comparison of coal made
into gas or burned under a boiler to be converted
into electricity. The ladies thanked me effusively
and brought their visit to a close. As they were about
to go through the door, one of them turned to me
and said: `We have enjoyed this visit very much,
but there is one question we would like to ask: What
is it that you make here?' "
The Brockton station was for a long time a show
plant of the Edison company, and had many distinguished
visitors, among them being Prof. Elihu
Thomson, who was present at the opening, and Sir
W. H. Preece, of London. The engineering methods
pursued formed the basis of similar installations in
Lawrence, Massachusetts, in November, 1883; in
Fall River, Massachusetts, in December, 1883; and
in Newburgh, New York, the following spring.
Another important plant of this period deserves
special mention, as it was the pioneer in the lighting
of large spaces by incandescent lamps. This installation
of five thousand lamps on the three-wire system
was made to illuminate the buildings at the Louisville,
Kentucky, Exposition in 1883, and, owing to the careful
surveys, calculations, and preparations of H. M.
Byllesby and the late Luther Stieringer, was completed
and in operation within six weeks after
the placing of the order. The Jury of Awards,
in presenting four medals to the Edison company,
took occasion to pay a high compliment to the
efficiency of the system. It has been thought by
many that the magnificent success of this plant
did more to stimulate the growth of the incandescent
lighting business than any other event in
the history of the Edison company. It was literally
the beginning of the electrical illumination of American
Expositions, carried later to such splendid displays
as those of the Chicago World's Fair in 1893,
Buffalo in 1901, and St. Louis in 1904.
Thus the art was set going in the United States
under many difficulties, but with every sign of coming
triumph. Reference has already been made to
the work abroad in Paris and London. The first
permanent Edison station in Europe was that at
Milan, Italy, for which the order was given as early
as May, 1882, by an enterprising syndicate. Less
than a year later, March 3, 1883, the installation was
ready and was put in operation, the Theatre Santa
Radegonda having been pulled down and a new central-
station building erected in its place--probably
the first edifice constructed in Europe for the
specific purpose of incandescent lighting. Here
"Jumbos" were installed from time to time, until at
last there were no fewer than ten of them; and current
was furnished to customers with a total of nearly
ten thousand lamps connected to the mains. This
pioneer system was operated continuously until
February 9, 1900, or for a period of about seventeen
years, when the sturdy old machines, still in excellent
condition, were put out of service, so that a larger
plant could be installed to meet the demand. This
new plant takes high-tension polyphase current from
a water-power thirty or forty miles away at Paderno,
on the river Adda, flowing from the Apennines;
but delivers low-tension direct current for distribution
to the regular Edison three-wire system throughout
Milan.
About the same time that southern Europe was
thus opened up to the new system, South America
came into line, and the first Edison central station
there was installed at Santiago, Chile, in the summer of
1883, under the supervision of Mr. W. N. Stewart.
This was the result of the success obtained with small
isolated plants, leading to the formation of an Edison
company. It can readily be conceived that at such
an extreme distance from the source of supply of
apparatus the plant was subject to many peculiar
difficulties from the outset, of which Mr. Stewart
speaks as follows: "I made an exhibition of the
`Jumbo' in the theatre at Santiago, and on the first
evening, when it was filled with the aristocracy of the
city, I discovered to my horror that the binding wire
around the armature was slowly stripping off and
going to pieces. We had no means of boring out the
field magnets, and we cut grooves in them. I think
the machine is still running (1907). The station
went into operation soon after with an equipment of
eight Edison `K' dynamos with certain conditions
inimical to efficiency, but which have not hindered
the splendid expansion of the local system. With
those eight dynamos we had four belts between each
engine and the dynamo. The steam pressure was
limited to seventy-five pounds per square inch. We
had two-wire underground feeders, sent without any
plans or specifications for their installation. The
station had neither voltmeter nor ammeter. The
current pressure was regulated by a galvanometer.
We were using coal costing $12 a ton, and were paid
for our light in currency worth fifty cents on the
dollar. The only thing I can be proud of in connection
with the plant is the fact that I did not design
it, that once in a while we made out to pay its operating
expenses, and that occasionally we could run it
for three months without a total breakdown."
It was not until 1885 that the first Edison station
in Germany was established; but the art was still
very young, and the plant represented pioneer lighting
practice in the Empire. The station at Berlin
comprised five boilers, and six vertical steam-engines
driving by belts twelve Edison dynamos, each of
about fifty-five horse-power capacity. A model of
this station is preserved in the Deutschen Museum at
Munich. In the bulletin of the Berlin Electricity
Works for May, 1908, it is said with regard to the
events that led up to the creation of the system, as
noted already at the Rathenau celebration: "The
year 1881 was a mile-stone in the history of the Allgemeine
Elektricitaets Gesellschaft. The International
Electrical Exposition at Paris was intended to place
before the eyes of the civilized world the achievements
of the century. Among the exhibits of that
Exposition was the Edison system of incandescent
lighting. IT BECAME THE BASIS OF MODERN HEAVY CURRENT
TECHNICS." The last phrase is italicized as being a
happy and authoritative description, as well as a
tribute.
This chapter would not be complete if it failed to
include some reference to a few of the earlier isolated
plants of a historic character. Note has already been
made of the first Edison plants afloat on the Jeannette
and Columbia, and the first commercial plant in the
New York lithographic establishment. The first mill
plant was placed in the woollen factory of James
Harrison at Newburgh, New York, about September
15, 1881. A year later, Mr. Harrison wrote with some
pride: "I believe my mill was the first lighted with
your electric light, and therefore may be called No. 1.
Besides being job No. 1 it is a No. 1 job, and a No. 1
light, being better and cheaper than gas and absolutely
safe as to fire." The first steam-yacht lighted
by incandescent lamps was James Gordon Bennett's
Namouna, equipped early in 1882 with a plant for
one hundred and twenty lamps of eight candlepower,
which remained in use there many years
afterward.
The first Edison plant in a hotel was started in
October, 1881, at the Blue Mountain House in the
Adirondacks, and consisted of two "Z" dynamos
with a complement of eight and sixteen candle lamps.
The hotel is situated at an elevation of thirty-five
hundred feet above the sea, and was at that time
forty miles from the railroad. The machinery was
taken up in pieces on the backs of mules from the
foot of the mountain. The boilers were fired by wood,
as the economical transportation of coal was a physical
impossibility. For a six-hour run of the plant one-
quarter of a cord of wood was required, at a cost of
twenty-five cents per cord.
The first theatre in the United States to be lighted
by an Edison isolated plant was the Bijou Theatre,
Boston. The installation of boilers, engines, dynamos,
wiring, switches, fixtures, three stage regulators,
and six hundred and fifty lamps, was completed in
eleven days after receipt of the order, and the plant
was successfully operated at the opening of the
theatre, on December 12, 1882.
The first plant to be placed on a United States
steamship was the one consisting of an Edison "Z"
dynamo and one hundred and twenty eight-candle
lamps installed on the Fish Commission's steamer
Albatross in 1883. The most interesting feature of
this installation was the employment of special deep-
sea lamps, supplied with current through a cable
nine hundred and forty feet in length, for the purpose
of alluring fish. By means of the brilliancy of the
lamps marine animals in the lower depths were attracted
and then easily ensnared.
CHAPTER XVIII
THE ELECTRIC RAILWAY
EDISON had no sooner designed his dynamo in
1879 than he adopted the same form of machine
for use as a motor. The two are shown in the Scientific
American of October 18, 1879, and are alike, except
that the dynamo is vertical and the motor lies in a
horizontal position, the article remarking: "Its construction
differs but slightly from the electric generator."
This was but an evidence of his early appreciation
of the importance of electricity as a motive power;
but it will probably surprise many people to know
that he was the inventor of an electric motor before
he perfected his incandescent lamp. His interest in
the subject went back to his connection with General
Lefferts in the days of the evolution of the stock
ticker. While Edison was carrying on his shop at
Newark, New Jersey, there was considerable excitement
in electrical circles over the Payne motor, in
regard to the alleged performance of which Governor
Cornell of New York and other wealthy capitalists
were quite enthusiastic. Payne had a shop in Newark,
and in one small room was the motor, weighing perhaps
six hundred pounds. It was of circular form,
incased in iron, with the ends of several small magnets
sticking through the floor. A pulley and belt, con-
nected to a circular saw larger than the motor,
permitted large logs of oak timber to be sawed with ease
with the use of two small cells of battery. Edison's
friend, General Lefferts, had become excited and was
determined to invest a large sum of money in the
motor company, but knowing Edison's intimate
familiarity with all electrical subjects he was wise
enough to ask his young expert to go and see the
motor with him. At an appointed hour Edison went
to the office of the motor company and found there
the venerable Professor Morse, Governor Cornell,
General Lefferts, and many others who had been
invited to witness a performance of the motor. They
all proceeded to the room where the motor was at
work. Payne put a wire in the binding-post of the
battery, the motor started, and an assistant began
sawing a heavy oak log. It worked beautifully, and so
great was the power developed, apparently, from the
small battery, that Morse exclaimed: "I am thankful
that I have lived to see this day." But Edison
kept a close watch on the motor. The results were
so foreign to his experience that he knew there was
a trick in it. He soon discovered it. While holding
his hand on the frame of the motor he noticed a
tremble coincident with the exhaust of an engine
across the alleyway, and he then knew that the
power came from the engine by a belt under the floor,
shifted on and off by a magnet, the other magnets
being a blind. He whispered to the General to put
his hand on the frame of the motor, watch the
exhaust, and note the coincident tremor. The General
did so, and in about fifteen seconds he said: "Well,
Edison, I must go now. This thing is a fraud." And
thus he saved his money, although others not so
shrewdly advised were easily persuaded to invest by
such a demonstration.
A few years later, in 1878, Edison went to Wyoming
with a group of astronomers, to test his tasimeter during
an eclipse of the sun, and saw the land white to harvest.
He noticed the long hauls to market or elevator
that the farmers had to make with their loads of grain
at great expense, and conceived the idea that as ordinary
steam-railroad service was too costly, light
electric railways might be constructed that could
be operated automatically over simple tracks, the
propelling motors being controlled at various points.
Cheap to build and cheap to maintain, such roads would
be a great boon to the newer farming regions of the
West, where the highways were still of the crudest character,
and where transportation was the gravest difficulty
with which the settlers had to contend. The
plan seems to have haunted him, and he had no sooner
worked out a generator and motor that owing to their
low internal resistance could be operated efficiently,
than he turned his hand to the practical trial of such
a railroad, applicable to both the haulage of freight
and the transportation of passengers. Early in 1880,
when the tremendous rush of work involved in the
invention of the incandescent lamp intermitted a little,
he began the construction of a stretch of track
close to the Menlo Park laboratory, and at the same
time built an electric locomotive to operate over it.
This is a fitting stage at which to review briefly
what had been done in electric traction up to that
date. There was absolutely no art, but there had
been a number of sporadic and very interesting
experiments made. The honor of the first attempt of
any kind appears to rest with this country and with
Thomas Davenport, a self-trained blacksmith, of
Brandon, Vermont, who made a small model of a
circular electric railway and cars in 1834, and
exhibited it the following year in Springfield, Boston,
and other cities. Of course he depended upon
batteries for current, but the fundamental idea was
embodied of using the track for the circuit, one rail
being positive and the other negative, and the motor
being placed across or between them in multiple arc
to receive the current. Such are also practically the
methods of to-day. The little model was in good
preservation up to the year 1900, when, being shipped
to the Paris Exposition, it was lost, the steamer that
carried it foundering in mid-ocean. The very broad
patent taken out by this simple mechanic, so far
ahead of his times, was the first one issued in America
for an electric motor. Davenport was also the first
man to apply electric power to the printing-press,
in 1840. In his traction work he had a close second
in Robert Davidson, of Aberdeen, Scotland, who in
1839 operated both a lathe and a small locomotive
with the motor he had invented. His was the credit
of first actually carrying passengers--two at a time,
over a rough plank road--while it is said that his was
the first motor to be tried on real tracks, those of
the Edinburgh-Glasgow road, making a speed of four
miles an hour.
The curse of this work and of all that succeeded it
for a score of years was the necessity of depending
upon chemical batteries for current, the machine
usually being self-contained and hauling the batteries
along with itself, as in the case of the famous
Page experiments in April, 1851, when a speed of
nineteen miles an hour was attained on the line of
the Washington & Baltimore road. To this unfruitful
period belonged, however, the crude idea of taking
the current from a stationary source of power by
means of an overhead contact, which has found its
practical evolution in the modern ubiquitous trolley;
although the patent for this, based on his caveat of
1879, was granted several years later than that to
Stephen D. Field, for the combination of an electric
motor operated by means of a current from a stationary
dynamo or source of electricity conducted
through the rails. As a matter of fact, in 1856 and
again in 1875, George F. Green, a jobbing machinist,
of Kalamazoo, Michigan, built small cars and tracks
to which current was fed from a distant battery,
enough energy being utilized to haul one hundred
pounds of freight or one passenger up and down a
"road" two hundred feet long. All the work prior
to the development of the dynamo as a source of
current was sporadic and spasmodic, and cannot be
said to have left any trace on the art, though it
offered many suggestions as to operative methods.
The close of the same decade of the nineteenth
century that saw the electric light brought to perfection,
saw also the realization in practice of all the
hopes of fifty years as to electric traction. Both
utilizations depended upon the supply of current now
cheaply obtainable from the dynamo. These arts
were indeed twins, feeding at inexhaustible breasts.
In 1879, at the Berlin Exhibition, the distinguished
firm of Siemens, to whose ingenuity and enterprise
electrical development owes so much, installed a road
about one-third of a mile in length, over which the
locomotive hauled a train of three small cars at a
speed of about eight miles an hour, carrying some
twenty persons every trip. Current was fed from a
dynamo to the motor through a central third rail, the
two outer rails being joined together as the negative
or return circuit. Primitive but essentially successful,
this little road made a profound impression on the
minds of many inventors and engineers, and marked
the real beginning of the great new era, which has
already seen electricity applied to the operation of
main lines of trunk railways. But it is not to be supposed
that on the part of the public there was any
great amount of faith then discernible; and for some
years the pioneers had great difficulty, especially in
this country, in raising money for their early modest
experiments. Of the general conditions at this
moment Frank J. Sprague says in an article in the
Century Magazine of July, 1905, on the creation of
the new art: "Edison was perhaps nearer the verge
of great electric-railway possibilities than any other
American. In the face of much adverse criticism
he had developed the essentials of the low-internal-
resistance dynamo with high-resistance field, and
many of the essential features of multiple-arc
distribution, and in 1880 he built a small road at his
laboratory at Menlo Park."
On May 13th of the year named this interesting
road went into operation as the result of hard and
hurried work of preparation during the spring months.
The first track was about a third of a mile in length,
starting from the shops, following a country road, passing
around a hill at the rear and curving home, in the
general form of the letter "U." The rails were very
light. Charles T. Hughes, who went with Edison in
1879, and was in charge of much of the work, states
that they were "second" street-car rails, insulated
with tar canvas paper and things of that sort--
"asphalt." They were spiked down on ordinary
sleepers laid upon the natural grade, and the gauge
was about three feet six inches. At one point the
grade dropped some sixty feet in a distance of three
hundred, and the curves were of recklessly short
radius. The dynamos supplying current to the road
were originally two of the standard size "Z" machines
then being made at the laboratory, popularly known
throughout the Edison ranks as "Longwaisted Mary
Anns," and the circuits from these were carried out
to the rails by underground conductors. They were
not large--about twelve horse-power each--generating
seventy-five amperes of current at one hundred and
ten volts, so that not quite twenty-five horse-power
of electrical energy was available for propulsion.
The locomotive built while the roadbed was getting
ready was a four-wheeled iron truck, an ordinary flat
dump-car about six feet long and four feet wide,
upon which was mounted a "Z" dynamo used as a
motor, so that it had a capacity of about twelve
horsepower. This machine was laid on its side, with the
armature end coming out at the front of the
locomotive, and the motive power was applied to the
driving-axle by a cumbersome series of friction pulleys.
Each wheel of the locomotive had a metal rim
and a centre web of wood or papier-mache, and the
current picked up by one set of wheels was carried
through contact brushes and a brass hub to the
motor; the circuit back to the track, or other rail,
being closed through the other wheels in a similar
manner. The motor had its field-magnet circuit in
permanent connection as a shunt across the rails,
protected by a crude bare copper-wire safety-catch.
A switch in the armature circuit enabled the motorman
to reverse the direction of travel by reversing the
current flow through the armature coils.
Things went fairly well for a time on that memorable
Thursday afternoon, when all the laboratory
force made high holiday and scrambled for foothold
on the locomotive for a trip; but the friction gearing
was not equal to the sudden strain put upon it during
one run and went to pieces. Some years later, also,
Daft again tried friction gear in his historical experiments
on the Manhattan Elevated road, but the results
were attended with no greater success. The
next resort of Edison was to belts, the armature shafting
belted to a countershaft on the locomotive frame,
and the countershaft belted to a pulley on the car-
axle. The lever which threw the former friction gear
into adjustment was made to operate an idler pulley
for tightening the axle-belt. When the motor was
started, the armature was brought up to full revolution
and then the belt was tightened on the car-
axle, compelling motion of the locomotive. But the
belts were liable to slip a great deal in the process,
and the chafing of the belts charred them badly. If
that did not happen, and if the belt was made taut
suddenly, the armature burned out--which it did
with disconcerting frequency. The next step was to
use a number of resistance-boxes in series with the
armature, so that the locomotive could start with those
in circuit, and then the motorman could bring it up
to speed gradually by cutting one box out after the
other. To stop the locomotive, the armature circuit
was opened by the main switch, stopping the flow of
current, and then brakes were applied by long levers.
Matters generally and the motors in particular went
much better, even if the locomotive was so freely
festooned with resistance-boxes all of perceptible
weight and occupying much of the limited space.
These details show forcibly and typically the painful
steps of advance that every inventor in this new
field had to make in the effort to reach not alone
commercial practicability, but mechanical feasibility.
It was all empirical enough; but that was the only
way open even to the highest talent.
Smugglers landing laces and silks have been known
to wind them around their bodies, as being less
ostentatious than carrying them in a trunk. Edison
thought his resistance-boxes an equally superfluous
display, and therefore ingeniously wound some copper
resistance wire around one of the legs of the motor
field magnet, where it was out of the way, served as
a useful extra field coil in starting up the motor, and
dismissed most of the boxes back to the laboratory;
a few being retained under the seat for chance emergencies.
Like the boxes, this coil was in series with
the armature, and subject to plugging in and out at
will by the motorman. Thus equipped, the locomotive
was found quite satisfactory, and long did yeoman
service. It was given three cars to pull, one an
open awning-car with two park benches placed back to
back; one a flat freight-car, and one box-car dubbed
the "Pullman," with which Edison illustrated a system
of electric braking. Although work had been
begun so early in the year, and the road had been
operating since May, it was not until July that Edison
executed any application for patents on his
"electromagnetic railway engine," or his ingenious braking
system. Every inventor knows how largely his fate
lies in the hands of a competent and alert patent
attorney, in both the preparation and the prosecution
of his case; and Mr. Sprague is justified in observing
in his Century article: ""The paucity of controlling
claims obtained in these early patents is remarkable."
It is notorious that Edison did not then enjoy the
skilful aid in safeguarding his ideas that he commanded
later.
The daily newspapers and technical journals lost
no time in bringing the road to public attention, and
the New York Herald of June 25th was swift to suggest
that here was the locomotive that would be
"most pleasing to the average New Yorker, whose
head has ached with noise, whose eyes have been
filled with dust, or whose clothes have been ruined
with oil." A couple of days later, the Daily Graphic
illustrated and described the road and published a
sketch of a one-hundred-horse-power electric locomotive
for the use of the Pennsylvania Railroad between
Perth Amboy and Rahway. Visitors, of
course, were numerous, including many curious,
sceptical railroad managers, few if any of whom except
Villard could see the slightest use for the new
motive power. There is, perhaps, some excuse for
such indifference. No men in the world have more
new inventions brought to them than railroad managers,
and this was the rankest kind of novelty. It
was not, indeed, until a year later, in May, 1881, that
the first regular road collecting fares was put in
operation--a little stretch of one and a half miles
from Berlin to Lichterfelde, with one miniature motorcar.
Edison was in reality doing some heavy electric-
railway engineering, his apparatus full of ideas,
suggestions, prophecies; but to the operators of long
trunk lines it must have seemed utterly insignificant
and "excellent fooling."
Speaking of this situation, Mr. Edison says: "One
day Frank Thomson, the President of the Pennsylvania
Railroad, came out to see the electric light and
the electric railway in operation. The latter was then
about a mile long. He rode on it. At that time I
was getting out plans to make an electric locomotive
of three hundred horse-power with six-foot drivers,
with the idea of showing people that they could
dispense with their steam locomotives. Mr. Thomson
made the objection that it was impracticable, and
that it would be impossible to supplant steam. His
great experience and standing threw a wet blanket
on my hopes. But I thought he might perhaps be
mistaken, as there had been many such instances
on record. I continued to work on the plans, and
about three years later I started to build the locomotive
at the works at Goerck Street, and had it about
finished when I was switched off on some other work.
One of the reasons why I felt the electric railway to
be eminently practical was that Henry Villard, the
President of the Northern Pacific, said that one of
the greatest things that could be done would be to
build right-angle feeders into the wheat-fields of
Dakota and bring in the wheat to the main lines,
as the farmers then had to draw it from forty to
eighty miles. There was a point where it would not
pay to raise it at all; and large areas of the country
were thus of no value. I conceived the idea of building
a very light railroad of narrow gauge, and had
got all the data as to the winds on the plains, and
found that it would be possible with very large windmills
to supply enough power to drive those wheat
trains."
Among others who visited the little road at this
juncture were persons interested in the Manhattan
Elevated system of New York, on which experiments
were repeatedly tried later, but which was not destined
to adopt a method so obviously well suited to
all the conditions until after many successful
demonstrations had been made on elevated roads elsewhere.
It must be admitted that Mr. Edison was not very
profoundly impressed with the desire entertained in
that quarter to utilize any improvement, for he
remarks: "When the Elevated Railroad in New York,
up Sixth Avenue, was started there was a great
clamor about the noise, and injunctions were threatened.
The management engaged me to make a report
on the cause of the noise. I constructed an
instrument that would record the sound, and set out
to make a preliminary report, but I found that they
never intended to do anything but let the people
complain."
It was upon the co-operation of Villard that Edison
fell back, and an agreement was entered into between
them on September 14, 1881, which provided that the
latter would "build two and a half miles of electric
railway at Menlo Park, equipped with three cars,
two locomotives, one for freight, and one for
passengers, capacity of latter sixty miles an hour.
Capacity freight engine, ten tons net freight; cost
of handling a ton of freight per mile per horse-power
to be less than ordinary locomotive.... If experiments
are successful, Villard to pay actual outlay in
experiments, and to treat with the Light Company
for the installation of at least fifty miles of electric
railroad in the wheat regions." Mr. Edison is authority
for the statement that Mr. Villard advanced between
$35,000 and $40,000, and that the work done
was very satisfactory; but it did not end at that
time in any practical results, as the Northern Pacific
went into the hands of a receiver, and Mr. Villard's
ability to help was hopelessly crippled. The directors
of the Edison Electric Light Company could not be
induced to have anything to do with the electric
railway, and Mr. Insull states that the money advanced
was treated by Mr. Edison as a personal loan and repaid
to Mr. Villard, for whom he had a high admiration
and a strong feeling of attachment. Mr. Insull says:
"Among the financial men whose close personal
friendship Edison enjoyed, I would mention Henry
Villard, who, I think, had a higher appreciation of
the possibilities of the Edison system than probably
any other man of his time in Wall Street. He dropped
out of the business at the time of the consolidation
of the Thomson-Houston Company with the Edison
General Electric Company; but from the earliest days
of the business, when it was in its experimental period,
when the Edison light and power system was but an
idea, down to the day of his death, Henry Villard continued
a strong supporter not only with his influence,
but with his money. He was the first capitalist to
back individually Edison's experiments in electric
railways."
In speaking of his relationships with Mr. Villard at
this time, Edison says: "When Villard was all broken
down, and in a stupor caused by his disasters in
connection with the Northern Pacific, Mrs. Villard sent
for me to come and cheer him up. It was very difficult
to rouse him from his despair and apathy, but
I talked about the electric light to him, and its
development, and told him that it would help him win
it all back and put him in his former position. Villard
made his great rally; he made money out of the electric
light; and he got back control of the Northern
Pacific. Under no circumstances can a hustler be
kept down. If he is only square, he is bound to get
back on his feet. Villard has often been blamed and
severely criticised, but he was not the only one to
blame. His engineers had spent $20,000,000 too
much in building the road, and it was not his fault
if he found himself short of money, and at that time
unable to raise any more."
Villard maintained his intelligent interest in electric-
railway development, with regard to which Edison
remarks: "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."
At this point it may be well to cite some other
statements of Edison as to kindred work, with which
he has not usually been associated in the public mind.
"In the same manner I had worked out for the Manhattan
Elevated Railroad a system of electric trains,
and had the control of each car centred at one place
--multiple control. This was afterward worked out
and made practical by Frank Sprague. I got up a
slot contact for street railways, and have a patent on
it--a sliding contact in a slot. Edward Lauterbach
was connected with the Third Avenue Railroad in
New York--as counsel--and I told him he was mak-
ing a horrible mistake putting in the cable. I told
him to let the cable stand still and send electricity
through it, and he would not have to move hundreds
of tons of metal all the time. He would rue the day
when he put the cable in." It cannot be denied that
the prophecy was fulfilled, for the cable was the beginning
of the frightful financial collapse of the system,
and was torn out in a few years to make way for the
triumphant "trolley in the slot."
Incidental glimpses of this work are both amusing
and interesting. Hughes, who was working on the
experimental road with Mr. Edison, tells the following
story: "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.' " To the correspondence of Grosvenor
P. Lowrey we are indebted for a similar reminiscence,
under date of June 5, 1880: "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."
All this rough-and-ready dealing with grades and
curves was not mere horse-play, but had a serious purpose
underlying it, every trip having its record as to
some feature of defect or improvement. One particular
set of experiments relating to such work was
made on behalf of visitors from South America, and
were doubtless the first tests of the kind made for
that continent, where now many fine electric street
and interurban railway systems are in operation.
Mr. Edison himself supplies the following data:
"During the electric-railway experiments at Menlo
Park, we had a short spur of track up one of the
steep gullies. The experiment came about in this
way. Bogota, the capital of Columbia, is reached
on muleback--or was--from Honda on the headwaters
of the Magdalena River. There were parties
who wanted to know if transportation over the mule
route could not be done by electricity. They said the
grades were excessive, and it would cost too much to
do it with steam locomotives, even if they could
climb the grades. I said: `Well, it can't be much
more than 45 per cent.; we will try that first. If it
will do that it will do anything else.' I started at
45 per cent. I got up an electric locomotive with a
grip on the rail by which it went up the 45 per cent.
grade. Then they said the curves were very short.
I put the curves in. We started the locomotive with
nobody on it, and got up to twenty miles an hour,
taking those curves of very short radius; but it was
weeks before we could prevent it from running off.
We had to bank the tracks up to an angle of thirty
degrees before we could turn the curve and stay on.
These Spanish parties were perfectly satisfied we could
put in an electric railway from Honda to Bogota
successfully, and then they disappeared. I have never
seen them since. As usual, I paid for the experiment."
In the spring of 1883 the Electric Railway Company
of America was incorporated in the State of
New York with a capital of $2,000,000 to develop
the patents and inventions of Edison and Stephen
D. Field, to the latter of whom the practical work of
active development was confided, and in June of the
same year an exhibit was made at the Chicago Railway
Exposition, which attracted attention throughout
the country, and did much to stimulate the growing
interest in electric-railway work. With the aid
of Messrs. F. B. Rae, C. L. Healy, and C. O. Mailloux
a track and locomotive were constructed for the company
by Mr. Field and put in service in the gallery
of the main exhibition building. The track curved
sharply at either end on a radius of fifty-six feet, and
the length was about one-third of a mile. The locomotive
named "The Judge," after Justice Field, an
uncle of Stephen D. Field, took current from a central
rail between the two outer rails, that were the return
circuit, the contact being a rubbing wire brush on
each side of the "third rail," answering the same purpose
as the contact shoe of later date. The locomotive
weighed three tons, was twelve feet long, five
feet wide, and made a speed of nine miles an hour
with a trailer car for passengers. Starting on June
5th, when the exhibition closed on June 23d this tiny
but typical road had operated for over 118 hours, had
made over 446 miles, and had carried 26,805 passengers.
After the exposition closed the outfit was
taken during the same year to the exposition at
Louisville, Kentucky, where it was also successful,
carrying a large number of passengers. It deserves
note that at Chicago regular railway tickets were
issued to paying passengers, the first ever employed
on American electric railways.
With this modest but brilliant demonstration, to
which the illustrious names of Edison and Field were
attached, began the outburst of excitement over
electric railways, very much like the eras of speculation
and exploitation that attended only a few years
earlier the introduction of the telephone and the
electric light, but with such significant results that
the capitalization of electric roads in America is now
over $4,000,000,000, or twice as much as that of the
other two arts combined. There was a tremendous
rush into the electric-railway field after 1883, and an
outburst of inventive activity that has rarely, if ever,
been equalled. It is remarkable that, except Siemens,
no European achieved fame in this early work, while
from America the ideas and appliances of Edison,
Van Depoele, Sprague, Field, Daft, and Short have
been carried and adopted all over the world.
Mr. Edison was consulting electrician for the
Electric Railway Company, but neither a director
nor an executive officer. Just what the trouble was
as to the internal management of the corporation it
is hard to determine a quarter of a century later; but
it was equipped with all essential elements to dominate
an art in which after its first efforts it remained
practically supine and useless, while other interests
forged ahead and reaped both the profit and the glory.
Dissensions arose between the representatives of the
Field and Edison interests, and in April, 1890, the
Railway Company assigned its rights to the Edison
patents to the Edison General Electric Company,
recently formed by the consolidation of all the
branches of the Edison light, power, and manufacturing
industry under one management. The only
patent rights remaining to the Railway Company
were those under three Field patents, one of which,
with controlling claims, was put in suit June, 1890,
against the Jamaica & Brooklyn Road Company, a
customer of the Edison General Electric Company.
This was, to say the least, a curious and anomalous
situation. Voluminous records were made by both
parties to the suit, and in the spring of 1894 the case
was argued before the late Judge Townsend, who wrote
a long opinion dismissing the bill of complaint.[15] The
student will find therein a very complete and careful
study of the early electric-railway art. After this
decision was rendered, the Electric Railway Company
remained for several years in a moribund condition,
and on the last day of 1896 its property was placed
in the hands of a receiver. In February of 1897 the
receiver sold the three Field patents to their original
owner, and he in turn sold them to the Westinghouse
Electric and Manufacturing Company. The Railway
Company then went into voluntary dissolution, a sad
example of failure to seize the opportunity at the
psychological moment, and on the part of the inventor
to secure any adequate return for years of
effort and struggle in founding one of the great arts.
Neither of these men was squelched by such a calamitous
result, but if there were not something of bitterness
in their feelings as they survey what has come
of their work, they would not be human.
As a matter of fact, Edison retained a very lively
interest in electric-railway progress long after the
pregnant days at Menlo Park, one of the best evidences
of which is an article in the New York Electrical
Engineer of November 18, 1891, which describes
some important and original experiments in the direction
of adapting electrical conditions to the larger
cities. The overhead trolley had by that time begun
its victorious career, but there was intense hostility
displayed toward it in many places because of the
inevitable increase in the number of overhead wires,
which, carrying, as they did, a current of high voltage
and large quantity, were regarded as a menace to life
and property. Edison has always manifested a
strong objection to overhead wires in cities, and
urged placing them underground; and the outcry
against the overhead "deadly" trolley met with his
instant sympathy. His study of the problem brought
him to the development of the modern "substation,"
although the twists that later evolutions have given
the idea have left it scarcely recognizable.
[15] See 61 Fed. Rep. 655.
Mr. Villard, as President of the Edison General
Electric Company, requested Mr. Edison, as electrician
of the company, to devise a street-railway
system which should be applicable to the largest
cities where the use of the trolley would not be
permitted, where the slot conduit system would not be
used, and where, in general, the details of construction
should be reduced to the simplest form. The
limits imposed practically were such as to require that
the system should not cost more than a cable road to
install. Edison reverted to his ingenious lighting plan
of years earlier, and thus settled on a method by
which current should be conveyed from the power
plant at high potential to motor-generators placed
below the ground in close proximity to the rails.
These substations would convert the current received
at a pressure of, say, one thousand volts to one of
twenty volts available between rail and rail, with a
corresponding increase in the volume of the current.
With the utilization of heavy currents at low voltage
it became necessary, of course, to devise apparatus
which should be able to pick up with absolute certainty
one thousand amperes of current at this press-
ure through two inches of mud, if necessary. With
his wonted activity and fertility Edison set about
devising such a contact, and experimented with metal
wheels under all conditions of speed and track conditions.
It was several months before he could convey
one hundred amperes by means of such contacts,
but he worked out at last a satisfactory device which
was equal to the task. The next point was to secure a
joint between contiguous rails such as would permit of
the passage of several thousand amperes without
introducing undue resistance. This was also accomplished.
Objections were naturally made to rails out in the
open on the street surface carrying large currents at
a potential of twenty volts. It was said that vehicles
with iron wheels passing over the tracks and spanning
the two rails would short-circuit the current,
"chew" themselves up, and destroy the dynamos
generating the current by choking all that tremendous
amount of energy back into them. Edison tackled
the objection squarely and short-circuited his track
with such a vehicle, but succeeded in getting only
about two hundred amperes through the wheels, the
low voltage and the insulating properties of the axle-
grease being sufficient to account for such a result.
An iron bar was also used, polished, and with a man
standing on it to insure solid contact; but only one
thousand amperes passed through it--i.e., the amount
required by a single car, and, of course, much less than
the capacity of the generators able to operate a
system of several hundred cars.
Further interesting experiments showed that the
expected large leakage of current from the rails in
wet weather did not materialize. Edison found that
under the worst conditions with a wet and salted
track, at a potential difference of twenty volts
between the two rails, the extreme loss was only two
and one-half horse-power. In this respect the
phenomenon followed the same rule as that to which
telegraph wires are subject--namely, that the loss of
insulation is greater in damp, murky weather when
the insulators are covered with wet dust than during
heavy rains when the insulators are thoroughly
washed by the action of the water. In like manner
a heavy rain-storm cleaned the tracks from the
accumulations due chiefly to the droppings of the horses,
which otherwise served largely to increase the conductivity.
Of course, in dry weather the loss of current
was practically nothing, and, under ordinary
conditions, Edison held, his system was in respect to
leakage and the problems of electrolytic attack of
the current on adjacent pipes, etc., as fully insulated
as the standard trolley network of the day. The cost
of his system Mr. Edison placed at from $30,000 to
$100,000 per mile of double track, in accordance with
local conditions, and in this respect comparing very
favorably with the cable systems then so much in
favor for heavy traffic. All the arguments that could
be urged in support of this ingenious system are
tenable and logical at the present moment; but the
trolley had its way except on a few lines where the
conduit-and-shoe method was adopted; and in the
intervening years the volume of traffic created and
handled by electricity in centres of dense population
has brought into existence the modern subway.
But down to the moment of the preparation of this
biography, Edison has retained an active interest in
transportation problems, and his latest work has
been that of reviving the use of the storage battery
for street-car purposes. At one time there were a
number of storage-battery lines and cars in operation
in such cities as Washington, New York, Chicago,
and Boston; but the costs of operation and maintenance
were found to be inordinately high as compared
with those of the direct-supply methods, and the battery
cars all disappeared. The need for them under
many conditions remained, as, for example, in places
in Greater New York where the overhead trolley wires
are forbidden as objectionable, and where the ground
is too wet or too often submerged to permit of the
conduit with the slot. Some of the roads in Greater
New York have been anxious to secure such cars, and,
as usual, the most resourceful electrical engineer and
inventor of his times has made the effort. A special
experimental track has been laid at the Orange
laboratory, and a car equipped with the Edison storage
battery and other devices has been put under
severe and extended trial there and in New York.
Menlo Park, in ruin and decay, affords no traces of
the early Edison electric-railway work, but the crude
little locomotive built by Charles T. Hughes was rescued
from destruction, and has become the property of the
Pratt Institute, of Brooklyn, towhose thousands of
technical students it is a constant example and incentive.
It was loaned in 1904 to the Association of Edison
Illuminating Companies, and by it exhibited as part of the
historical Edison collection at the St. Louis Exposition.
EDISON
HIS LIFE AND INVENTIONS
CHAPTER XIX
MAGNETIC ORE MILLING WORK
DURING the Hudson-Fulton celebration of October,
1909, Burgomaster Van Leeuwen, of Amsterdam,
member of the delegation sent officially from
Holland to escort the Half Moon and participate in
the functions of the anniversary, paid a visit to the
Edison laboratory at Orange to see the inventor, who
may be regarded as pre-eminent among those of
Dutch descent in this country. Found, as usual, hard
at work--this time on his cement house, of which he
showed the iron molds--Edison took occasion to remark
that if he had achieved anything worth while,
it was due to the obstinacy and pertinacity he had
inherited from his forefathers. To which it may be
added that not less equally have the nature of
inheritance and the quality of atavism been exhibited
in his extraordinary predilection for the miller's art.
While those Batavian ancestors on the low shores of
the Zuyder Zee devoted their energies to grinding grain,
he has been not less assiduous than they in reducing
the rocks of the earth itself to flour.
Although this phase of Mr. Edison's diverse activities
is not as generally known to the world as many
others of a more popular character, the milling of
low-grade auriferous ores and the magnetic separation
of iron ores have been subjects of engrossing
interest and study to him for many years. Indeed,
his comparatively unknown enterprise of separating
magnetically and putting into commercial form low-
grade iron ore, as carried on at Edison, New Jersey,
proved to be the most colossal experiment that he
has ever made.
If a person qualified to judge were asked to answer
categorically as to whether or not that enterprise
was a failure, he could truthfully answer both yes
and no. Yes, in that circumstances over which Mr.
Edison had no control compelled the shutting down
of the plant at the very moment of success; and no,
in that the mechanically successful and commercially
practical results obtained, after the exercise of
stupendous efforts and the expenditure of a fortune, are
so conclusive that they must inevitably be the reliance
of many future iron-masters. In other words, Mr.
Edison was at least a quarter of a century ahead of
the times in the work now to be considered.
Before proceeding to a specific description of this
remarkable enterprise, however, let us glance at an
early experiment in separating magnetic iron sands
on the Atlantic sea-shore: "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 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." This incident was really the prelude
to the development set forth in this chapter.
In the early eighties Edison became familiar with
the fact that the Eastern steel trade was suffering
a disastrous change, and that business was slowly
drifting westward, chiefly by reason of the discovery
and opening up of enormous deposits of high-grade
iron ore in the upper peninsula of Michigan. This
ore could be excavated very cheaply by means of
improved mining facilities, and transported at low
cost to lake ports. Hence the iron and steel mills
east of the Alleghanies--compelled to rely on limited
local deposits of Bessemer ore, and upon foreign ores
which were constantly rising in value--began to sustain
a serious competition with Western mills, even
in Eastern markets.
Long before this situation arose, it had been recognized
by Eastern iron-masters that sooner or later the
deposits of high-grade ore would be exhausted, and,
in consequence, there would ensue a compelling necessity
to fall back on the low-grade magnetic ores.
For many years it had been a much-discussed question
how to make these ores available for transporta-
tion to distant furnaces. To pay railroad charges on
ores carrying perhaps 80 to 90 per cent. of useless
material would be prohibitive. Hence the elimination
of the worthless "gangue" by concentration of
the iron particles associated with it, seemed to be
the only solution of the problem.
Many attempts had been made in by-gone days to
concentrate the iron in such ores by water processes,
but with only a partial degree of success. The
impossibility of obtaining a uniform concentrate was a
most serious objection, had there not indeed been
other difficulties which rendered this method commercially
impracticable. It is quite natural, therefore,
that the idea of magnetic separation should have
occurred to many inventors. Thus we find numerous
instances throughout the last century of experiments
along this line; and particularly in the last
forty or fifty years, during which various attempts
have been made by others than Edison to perfect
magnetic separation and bring it up to something
like commercial practice. At the time he took up
the matter, however, no one seems to have realized
the full meaning of the tremendous problems involved.
From 1880 to 1885, while still very busy in the
development of his electric-light system, Edison found
opportunity to plan crushing and separating machinery.
His first patent on the subject was applied
for and issued early in 1880. He decided, after
mature deliberation, that the magnetic separation of
low-grade ores on a colossal scale at a low cost was
the only practical way of supplying the furnaceman
with a high quality of iron ore. It was his opinion
that it was cheaper to quarry and concentrate lean
ore in a big way than to attempt to mine, under adverse
circumstances, limited bodies of high-grade ore.
He appreciated fully the serious nature of the gigantic
questions involved; and his plans were laid
with a view to exercising the utmost economy in the
design and operation of the plant in which he
contemplated the automatic handling of many thousands
of tons of material daily. It may be stated as broadly
true that Edison engineered to handle immense
masses of stuff automatically, while his predecessors
aimed chiefly at close separation.
Reduced to its barest, crudest terms, the proposition
of magnetic separation is simplicity itself. A
piece of the ore (magnetite) may be reduced to powder
and the ore particles separated therefrom by the
help of a simple hand magnet. To elucidate the basic
principle of Edison's method, let the crushed ore fall
in a thin stream past such a magnet. The magnetic
particles are attracted out of the straight line of the
falling stream, and being heavy, gravitate inwardly
and fall to one side of a partition placed below. The
non-magnetic gangue descends in a straight line to
the other side of the partition. Thus a complete
separation is effected.
Simple though the principle appears, it was in its
application to vast masses of material and in the
solving of great engineering problems connected
therewith that Edison's originality made itself manifest
in the concentrating works that he established
in New Jersey, early in the nineties. Not only did he
develop thoroughly the refining of the crushed ore, so
that after it had passed the four hundred and eighty
magnets in the mill, the concentrates came out finally
containing 91 to 93 per cent. of iron oxide, but he
also devised collateral machinery, methods and processes
all fundamental in their nature. These are
too numerous to specify in detail, as they extended
throughout the various ramifications of the plant, but
the principal ones are worthy of mention, such as:
The giant rolls (for crushing).
Intermediate rolls.
Three-high rolls.
Giant cranes (215 feet long span).
Vertical dryer.
Belt conveyors.
Air separation.
Mechanical separation of phosphorus.
Briquetting.
That Mr. Edison's work was appreciated at the
time is made evident by the following extract from
an article describing the Edison plant, published in
The Iron Age of October 28, 1897; in which, after
mentioning his struggle with adverse conditions, it
says: "There is very little that is showy, from the
popular point of view, in the gigantic work which
Mr. Edison has done during these years, but to those
who are capable of grasping the difficulties encountered,
Mr. Edison appears in the new light of a brilliant
constructing engineer grappling with technical
and commercial problems of the highest order. His
genius as an inventor is revealed in many details of
the great concentrating plant.... But to our mind,
originality of the highest type as a constructor and
designer appears in the bold way in which he sweeps
aside accepted practice in this particular field and
attains results not hitherto approached. He pursues
methods in ore-dressing at which those who are
trained in the usual practice may well stand aghast.
But considering the special features of the problems
to be solved, his methods will be accepted as those
economically wise and expedient."
A cursory glance at these problems will reveal their
import. Mountains must be reduced to dust; all
this dust must be handled in detail, so to speak, and
from it must be separated the fine particles of iron
constituting only one-fourth or one-fifth of its mass;
and then this iron-ore dust must be put into such
shape that it could be commercially shipped and used.
One of the most interesting and striking investigations
made by Edison in this connection is worthy
of note, and may be related in his own words: "I
felt certain that there must be large bodies of magnetite
in the East, which if crushed and concentrated
would satisfy the wants of the Eastern furnaces for
steel-making. Having determined to investigate the
mountain regions of New Jersey, I constructed a very
sensitive magnetic needle, which would dip toward
the earth if brought over any considerable body of
magnetic iron ore. One of my laboratory assistants
went out with me and we visited many of the mines
of New Jersey, but did not find deposits of any magnitude.
One day, however, as we drove over a mountain
range, not known as iron-bearing land, I was astonished
to find that the needle was strongly attracted
and remained so; thus indicating that the whole mountain
was underlaid with vast bodies of magnetic ore.
"I knew it was a commercial problem to produce
high-grade Bessemer ore from these deposits, and
took steps to acquire a large amount of the property.
I also planned a great magnetic survey of the East,
and I believe it remains the most comprehensive of
its kind yet performed. I had a number of men survey
a strip reaching from Lower Canada to North
Carolina. The only instrument we used was the
special magnetic needle. We started in Lower Canada
and travelled across the line of march twenty-five
miles; then advanced south one thousand feet; then
back across the line of march again twenty-five miles;
then south another thousand feet, across again, and
so on. Thus we advanced all the way to North
Carolina, varying our cross-country march from two
to twenty-five miles, according to geological formation.
Our magnetic needle indicated the presence
and richness of the invisible deposits of magnetic ore.
We kept minute records of these indications, and
when the survey was finished we had exact information
of the deposits in every part of each State we
had passed through. We also knew the width, length,
and approximate depth of every one of these deposits,
which were enormous.
"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 there were over 200,000,000 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.
Edison realized from the start that the true
solution of this problem lay in the continuous treatment
of the material, with the maximum employment
of natural forces and the minimum of manual labor
and generated power. Hence, all his conceptions
followed this general principle so faithfully and completely
that we find in the plant embodying his ideas
the forces of momentum and gravity steadily in harness
and keeping the traces taut; while there was no
touch of the human hand upon the material from the
beginning of the treatment to its finish--the staff being
employed mainly to keep watch on the correct working
of the various processes.
It is hardly necessary to devote space to the beginnings
of the enterprise, although they are full
of interest. They served, however, to convince
Edison that if he ever expected to carry out his
scheme on the extensive scale planned, he could not
depend upon the market to supply suitable machinery
for important operations, but would be obliged to
devise and build it himself. Thus, outside the steam-
shovel and such staple items as engines, boilers,
dynamos, and motors, all of the diverse and complex
machinery of the entire concentrating plant, as
subsequently completed, was devised by him especially
for the purpose. The necessity for this was due to the
many radical variations made from accepted methods.
No such departure was as radical as that of the
method of crushing the ore. Existing machinery for
this purpose had been designed on the basis of mining
methods then in vogue, by which the rock was
thoroughly shattered by means of high explosives and
reduced to pieces of one hundred pounds or less. These
pieces were then crushed by power directly applied. If
a concentrating mill, planned to treat five or six thousand
tons per day, were to be operated on this basis
the investment in crushers and the supply of power
would be enormous, to say nothing of the risk of
frequent breakdowns by reason of multiplicity of
machinery and parts. From a consideration of these
facts, and with his usual tendency to upset traditional
observances, Edison conceived the bold idea of
constructing gigantic rolls which, by the force of
momentum, would be capable of crushing individual
rocks of vastly greater size than ever before attempted.
He reasoned that the advantages thus obtained would
be fourfold: a minimum of machinery and parts;
greater compactness; a saving of power; and greater
economy in mining. As this last-named operation
precedes the crushing, let us first consider it as it
was projected and carried on by him.
Perhaps quarrying would be a better term than
mining in this case, as Edison's plan was to approach
the rock and tear it down bodily. The faith
that "moves mountains" had a new opportunity. In
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