CHAPTER XXIX

THE SOCIAL SIDE OF EDISON

THE title of this chapter might imply that there is an unsocial side

to Edison. In a sense this is true, for no one is more impatient

or intolerant of interruption when deeply engaged in some line of

experiment. Then the caller, no matter how important or what his

mission, is likely to realize his utter insignificance and be sent away

without accomplishing his object. But, generally speaking, Edison is

easy tolerance itself, with a peculiar weakness toward those who have

the least right to make any demands on his time. Man is a social animal,

and that describes Edison; but it does not describe accurately the

inventor asking to be let alone.

Edison never sought Society; but "Society" has never ceased to seek

him, and to-day, as ever, the pressure upon him to give up his work and

receive honors, meet distinguished people, or attend public functions,

is intense. Only two or three years ago, a flattering invitation came

from one of the great English universities to receive a degree, but at

that moment he was deep in experiments on his new storage battery, and

nothing could budge him. He would not drop the work, and while highly

appreciative of the proposed honor, let it go by rather than quit for

a week or two the stern drudgery of probing for the fact and the truth.

Whether one approves or not, it is at least admirable stoicism, of which

the world has too little. A similar instance is that of a visit paid to

the laboratory by some one bringing a gold medal from a foreign society.

It was a very hot day in summer, the visitor was in full social regalia

of silk hat and frock-coat, and insisted that he could deliver the medal

only into Edison's hands. At that moment Edison, stripped pretty nearly

down to the buff, was at the very crisis of an important experiment, and

refused absolutely to be interrupted. He had neither sought nor expected

the medal; and if the delegate didn't care to leave it he could take it

away. At last Edison was overpersuaded, and, all dirty and perspiring as

he was, received the medal rather than cause the visitor to come again.

On one occasion, receiving a medal in New York, Edison forgot it on

the ferry-boat and left it behind him. A few years ago, when Edison

had received the Albert medal of the Royal Society of Arts, one of the

present authors called at the laboratory to see it. Nobody knew where

it was; hours passed before it could be found; and when at last the

accompanying letter was produced, it had an office date stamp right over

the signature of the royal president. A visitor to the laboratory with

one of these medallic awards asked Edison if he had any others. "Oh

yes," he said, "I have a couple of quarts more up at the house!" All

this sounds like lack of appreciation, but it is anything else than

that. While in Paris, in 1889, he wore the decoration of the Legion

of Honor whenever occasion required, but at all other times turned the

badge under his lapel "because he hated to have fellow-Americans think

he was showing off." And any one who knows Edison will bear testimony to

his utter absence of ostentation. It may be added that, in addition

to the two quarts of medals up at the house, there will be found at

Glenmont many other signal tokens of esteem and good-will--a beautiful

cigar-case from the late Tsar of Russia, bronzes from the Government of

Japan, steel trophies from Krupp, and a host of other mementos, to one

of which he thus refers: "When the experiments with the light were going

on at Menlo Park, Sarah Bernhardt came to America. One evening, Robert

L. Cutting, of New York, brought her out to see the light. She was a

terrific 'rubberneck.' She jumped all over the machinery, and I had one

man especially to guard her dress. She wanted to know everything. She

would speak in French, and Cutting would translate into English. She

stayed there about an hour and a half. Bernhardt gave me two pictures,

painted by herself, which she sent me from Paris."

Reference has already been made to the callers upon Edison; and to give

simply the names of persons of distinction would fill many pages of this

record. Some were mere consumers of time; others were gladly welcomed,

like Lord Kelvin, the greatest physicist of the last century, with whom

Edison was always in friendly communication. "The first time I saw Lord

Kelvin, he came to my laboratory at Menlo Park in 1876." (He

reported most favorably on Edison's automatic telegraph system at the

Philadelphia Exposition of 1876.) "I was then experimenting with sending

eight messages simultaneously over a wire by means of synchronizing

tuning-forks. I would take a wire with similar apparatus at both ends,

and would throw it over on one set of instruments, take it away, and get

it back so quickly that you would not miss it, thereby taking advantage

of the rapidity of electricity to perform operations. On my local wire

I got it to work very nicely. When Sir William Thomson (Kelvin) came in

the room, he was introduced to me, and had a number of friends with him.

He said: 'What have you here?' I told him briefly what it was. He then

turned around, and to my great surprise explained the whole thing to

his friends. Quite a different exhibition was given two weeks later by

another well-known Englishman, also an electrician, who came in with

his friends, and I was trying for two hours to explain it to him and

failed."

After the introduction of the electric light, Edison was more than ever

in demand socially, but he shunned functions like the plague, not

only because of the serious interference with work, but because of his

deafness. Some dinners he had to attend, but a man who ate little and

heard less could derive practically no pleasure from them. "George

Washington Childs was very anxious I should go down to Philadelphia to

dine with him. I seldom went to dinners. He insisted I should go--that

a special car would leave New York. It was for me to meet Mr. Joseph

Chamberlain. We had the private car of Mr. Roberts, President of the

Pennsylvania Railroad. We had one of those celebrated dinners that only

Mr. Childs could give, and I heard speeches from Charles Francis Adams

and different people. When I came back to the depot, Mr. Roberts

was there, and insisted on carrying my satchel for me. I never could

understand that."

Among the more distinguished visitors of the electric-lighting period

was President Diaz, with whom Edison became quite intimate. "President

Diaz, of Mexico, visited this country with Mrs. Diaz, a highly educated

and beautiful woman. She spoke very good English. They both took a deep

interest in all they saw. I don't know how it ever came about, as it is

not in my line, but I seemed to be delegated to show them around. I took

them to railroad buildings, electric-light plants, fire departments, and

showed them a great variety of things. It lasted two days." Of another

visit Edison says: "Sitting Bull and fifteen Sioux Indians came to

Washington to see the Great Father, and then to New York, and went

to the Goerck Street works. We could make some very good pyrotechnics

there, so we determined to give the Indians a scare. But it didn't work.

We had an arc there of a most terrifying character, but they never moved

a muscle." Another episode at Goerck Street did not find the visitors

quite so stoical. "In testing dynamos at Goerck Street we had a long

flat belt running parallel with the floor, about four inches above it,

and travelling four thousand feet a minute. One day one of the

directors brought in three or four ladies to the works to see the new

electric-light system. One of the ladies had a little poodle led by a

string. The belt was running so smoothly and evenly, the poodle did not

notice the difference between it and the floor, and got into the belt

before we could do anything. The dog was whirled around forty or fifty

times, and a little flat piece of leather came out--and the ladies

fainted."

A very interesting period, on the social side, was the visit paid by

Edison and his family to Europe in 1889, when he had made a splendid

exhibit of his inventions and apparatus at the great Paris Centennial

Exposition of that year, to the extreme delight of the French,

who welcomed him with open arms. The political sentiments that the

Exposition celebrated were not such as to find general sympathy in

monarchical Europe, so that the "crowned heads" were conspicuous by

their absence. It was not, of course, by way of theatrical antithesis

that Edison appeared in Paris at such a time. But the contrast was none

the less striking and effective. It was felt that, after all, that which

the great exposition exemplified at its best--the triumph of genius

over matter, over ignorance, over superstition--met with its due

recognition when Edison came to participate, and to felicitate a noble

nation that could show so much in the victories of civilization and the

arts, despite its long trials and its long struggle for liberty. It is

no exaggeration to say that Edison was greeted with the enthusiastic

homage of the whole French people. They could find no praise warm enough

for the man who had "organized the echoes" and "tamed the lightning,"

and whose career was so picturesque with eventful and romantic

development. In fact, for weeks together it seemed as though no Parisian

paper was considered complete and up to date without an article on

Edison. The exuberant wit and fancy of the feuilletonists seized

upon his various inventions evolving from them others of the most

extraordinary nature with which to bedazzle and bewilder the reader. At

the close of the Exposition Edison was created a Commander of the Legion

of Honor. His own exhibit, made at a personal expense of over $100,000,

covered several thousand square feet in the vast Machinery Hall, and was

centred around a huge Edison lamp built of myriads of smaller lamps of

the ordinary size. The great attraction, however, was the display of the

perfected phonograph. Several instruments were provided, and every day,

all day long, while the Exposition lasted, queues of eager visitors from

every quarter of the globe were waiting to hear the little machine

talk and sing and reproduce their own voices. Never before was such

a collection of the languages of the world made. It was the first

linguistic concourse since Babel times. We must let Edison tell the

story of some of his experiences:

"At the Universal Exposition at Paris, in 1889, I made a personal

exhibit covering about an acre. As I had no intention of offering to

sell anything I was showing, and was pushing no companies, the whole

exhibition was made for honor, and without any hope of profit. But the

Paris newspapers came around and wanted pay for notices of it, which we

promptly refused; whereupon there was rather a stormy time for a while,

but nothing was published about it.

"While at the Exposition I visited the Opera-House. The President of

France lent me his private box. The Opera-House was one of the first

to be lighted by the incandescent lamp, and the managers took great

pleasure in showing me down through the labyrinth containing the

wiring, dynamos, etc. When I came into the box, the orchestra played the

'Star-Spangled Banner,' and all the people in the house arose; whereupon

I was very much embarrassed. After I had been an hour at the play, the

manager came around and asked me to go underneath the stage, as they

were putting on a ballet of 300 girls, the finest ballet in Europe. It

seems there is a little hole on the stage with a hood over it, in which

the prompter sits when opera is given. In this instance it was not

occupied, and I was given the position in the prompter's seat, and saw

the whole ballet at close range.

"The city of Paris gave me a dinner at the new Hotel de Ville, which was

also lighted with the Edison system. They had a very fine installation

of machinery. As I could not understand or speak a word of French,

I went to see our minister, Mr. Whitelaw Reid, and got him to send a

deputy to answer for me, which he did, with my grateful thanks. Then the

telephone company gave me a dinner, and the engineers of France; and

I attended the dinner celebrating the fiftieth anniversary of the

discovery of photography. Then they sent to Reid my decoration, and they

tried to put a sash on me, but I could not stand for that. My wife had

me wear the little red button, but when I saw Americans coming I would

slip it out of my lapel, as I thought they would jolly me for wearing

it."

Nor was this all. Edison naturally met many of the celebrities of

France: "I visited the Eiffel Tower at the invitation of Eiffel. We went

to the top, where there was an extension and a small place in which was

Eiffel's private office. In this was a piano. When my wife and I arrived

at the top, we found that Gounod, the composer, was there. We stayed a

couple of hours, and Gounod sang and played for us. We spent a day at

Meudon, an old palace given by the government to Jansen, the astronomer.

He occupied three rooms, and there were 300. He had the grand

dining-room for his laboratory. He showed me a gyroscope he had got

up which made the incredible number of 4000 revolutions in a second. A

modification of this was afterward used on the French Atlantic lines for

making an artificial horizon to take observations for position at

sea. In connection with this a gentleman came to me a number of years

afterward, and I got out a part of some plans for him. He wanted to make

a gigantic gyroscope weighing several tons, to be run by an electric

motor and put on a sailing ship. He wanted this gyroscope to keep a

platform perfectly horizontal, no matter how rough the sea was. Upon

this platform he was going to mount a telescope to observe an eclipse

off the Gold Coast of Africa. But for some reason it was never

completed.

"Pasteur invited me to come down to the Institute, and I went and had

quite a chat with him. I saw a large number of persons being inoculated,

and also the whole modus operandi, which was very interesting. I saw one

beautiful boy about ten, the son of an English lord. His father was with

him. He had been bitten in the face, and was taking the treatment. I

said to Pasteur, 'Will he live?' 'No,' said he, 'the boy will be dead in

six days. He was bitten too near the top of the spinal column, and came

too late!'"

Edison has no opinion to offer as an expert on art, but has his own

standard of taste: "Of course I visited the Louvre and saw the Old

Masters, which I could not enjoy. And I attended the Luxembourg, with

modern masters, which I enjoyed greatly. To my mind, the Old Masters

are not art, and I suspect that many others are of the same opinion;

and that their value is in their scarcity and in the variety of men with

lots of money." Somewhat akin to this is a shrewd comment on one feature

of the Exposition: "I spent several days in the Exposition at Paris. I

remember going to the exhibit of the Kimberley diamond mines, and they

kindly permitted me to take diamonds from some of the blue earth which

they were washing by machinery to exhibit the mine operations. I found

several beautiful diamonds, but they seemed a little light weight to me

when I was picking them out. They were diamonds for exhibition purposes

--probably glass."

This did not altogether complete the European trip of 1889, for Edison

wished to see Helmholtz. "After leaving Paris we went to Berlin. The

French papers then came out and attacked me because I went to Germany;

and said I was now going over to the enemy. I visited all the things of

interest in Berlin; and then on my way home I went with Helmholtz

and Siemens in a private compartment to the meeting of the German

Association of Science at Heidelberg, and spent two days there. When

I started from Berlin on the trip, I began to tell American stories.

Siemens was very fond of these stories and would laugh immensely at

them, and could see the points and the humor, by his imagination; but

Helmholtz could not see one of them. Siemens would quickly, in

German, explain the point, but Helmholtz could not see it, although he

understood English, which Siemens could speak. Still the explanations

were made in German. I always wished I could have understood Siemens's

explanations of the points of those stories. At Heidelberg, my

assistant, Mr. Wangemann, an accomplished German-American, showed the

phonograph before the Association."

Then came the trip from the Continent to England, of which this will

certainly pass as a graphic picture: "When I crossed over to England

I had heard a good deal about the terrors of the English Channel as

regards seasickness. I had been over the ocean three times and did not

know what seasickness was, so far as I was concerned myself. I was told

that while a man might not get seasick on the ocean, if he met a good

storm on the Channel it would do for him. When we arrived at Calais

to cross over, everybody made for the restaurant. I did not care about

eating, and did not go to the restaurant, but my family did. I walked

out and tried to find the boat. Going along the dock I saw two small

smokestacks sticking up, and looking down saw a little boat. 'Where is

the steamer that goes across the Channel?' 'This is the boat.' There had

been a storm in the North Sea that had carried away some of the boats on

the German steamer, and it certainly looked awful tough outside. I said

to the man: 'Will that boat live in that sea?' 'Oh yes,' he said, 'but

we've had a bad storm.' So I made up my mind that perhaps I would get

sick this time. The managing director of the English railroad owning

this line was Forbes, who heard I was coming over, and placed the

private saloon at my disposal. The moment my family got in the room with

the French lady's maid and the rest, they commenced to get sick, so I

felt pretty sure I was in for it. We started out of the little inlet

and got into the Channel, and that boat went in seventeen directions

simultaneously. I waited awhile to see what was going to occur, and then

went into the smoking-compartment. Nobody was there. By-and-by the fun

began. Sounds of all kinds and varieties were heard in every direction.

They were all sick. There must have been 100 people aboard. I didn't

see a single exception except the waiters and myself. I asked one of the

waiters concerning the boat itself, and was taken to see the engineer,

and went down to look at the engines, and saw the captain. But I kept

mostly in the smoking-room. I was smoking a big cigar, and when a man

looked in I would give a big puff, and every time they saw that they

would go away and begin again. The English Channel is a holy terror, all

right, but it didn't affect me. I must be out of balance."

While in Paris, Edison had met Sir John Pender, the English "cable

king," and had received an invitation from him to make a visit to his

country residence: "Sir John Pender, the master of the cable system of

the world at that time, I met in Paris. I think he must have lived among

a lot of people who were very solemn, because I went out riding with

him in the Bois de Boulogne and started in to tell him American stories.

Although he was a Scotchman he laughed immoderately. He had the faculty

of understanding and quickly seeing the point of the stories; and

for three days after I could not get rid of him. Finally I made him

a promise that I would go to his country house at Foot's Cray, near

London. So I went there, and spent two or three days telling him

stories.

"While at Foot's Cray, I met some of the backers of Ferranti, then

putting up a gigantic alternating-current dynamo near London to send

ten or fifteen thousand volts up into the main district of the city for

electric lighting. I think Pender was interested. At any rate the people

invited to dinner were very much interested, and they questioned me as

to what I thought of the proposition. I said I hadn't any thought about

it, and could not give any opinion until I saw it. So I was taken up

to London to see the dynamo in course of construction and the methods

employed; and they insisted I should give them some expression of my

views. While I gave them my opinion, it was reluctantly; I did not want

to do so. I thought that commercially the thing was too ambitious, that

Ferranti's ideas were too big, just then; that he ought to have started

a little smaller until he was sure. I understand that this installation

was not commercially successful, as there were a great many troubles.

But Ferranti had good ideas, and he was no small man."

Incidentally it may be noted here that during the same year (1889) the

various manufacturing Edison lighting interests in America were brought

together, under the leadership of Mr. Henry Villard, and consolidated

in the Edison General Electric Company with a capital of no less than

$12,000,000 on an eight-per-cent.-dividend basis. The numerous Edison

central stations all over the country represented much more than that

sum, and made a splendid outlet for the product of the factories. A few

years later came the consolidation with the Thomson-Houston interests

in the General Electric Company, which under the brilliant and vigorous

management of President C. A. Coffin has become one of the greatest

manufacturing institutions of the country, with an output of apparatus

reaching toward $75,000,000 annually. The net result of both financial

operations was, however, to detach Edison from the special field of

invention to which he had given so many of his most fruitful years; and

to close very definitely that chapter of his life, leaving him free to

develop other ideas and interests as set forth in these volumes.

It might appear strange on the surface, but one of the reasons that most

influenced Edison to regrets in connection with the "big trade" of 1889

was that it separated him from his old friend and ally, Bergmann, who,

on selling out, saw a great future for himself in Germany, went

there, and realized it. Edison has always had an amused admiration for

Bergmann, and his "social side" is often made evident by his love of

telling stories about those days of struggle. Some of the stories were

told for this volume. "Bergmann came to work for me as a boy," says

Edison. "He started in on stock-quotation printers. As he was a rapid

workman and paid no attention to the clock, I took a fancy to him, and

gave him piece-work. He contrived so many little tools to cheapen the

work that he made lots of money. I even helped him get up tools until

it occurred to me that this was too rapid a process of getting rid of

my money, as I hadn't the heart to cut the price when it was originally

fair. After a year or so, Bergmann got enough money to start a small

shop in Wooster Street, New York, and it was at this shop that the

first phonographs were made for sale. Then came the carbon telephone

transmitter, a large number of which were made by Bergmann for the

Western Union. Finally came the electric light. A dynamo was installed

in Bergmann's shop to permit him to test the various small devices which

he was then making for the system. He rented power from a Jew who owned

the building. Power was supplied from a fifty-horse-power engine to

other tenants on the several floors. Soon after the introduction of the

big dynamo machine, the landlord appeared in the shop and insisted that

Bergmann was using more power than he was paying for, and said that

lately the belt on the engine was slipping and squealing. Bergmann

maintained that he must be mistaken. The landlord kept going among his

tenants and finally discovered the dynamo. 'Oh! Mr. Bergmann, now I know

where my power goes to,' pointing to the dynamo. Bergmann gave him a

withering look of scorn, and said, 'Come here and I will show you.'

Throwing off the belt and disconnecting the wires, he spun the armature

around by hand. 'There,' said Bergmann, 'you see it's not here that you

must look for your loss.' This satisfied the landlord, and he started

off to his other tenants. He did not know that that machine, when the

wires were connected, could stop his engine.

"Soon after, the business had grown so large that E. H. Johnson and I

went in as partners, and Bergmann rented an immense factory building

at the corner of Avenue B and East Seventeenth Street, New York, six

stories high and covering a quarter of a block. Here were made all the

small things used on the electric-lighting system, such as sockets,

chandeliers, switches, meters, etc. In addition, stock tickers,

telephones, telephone switchboards, and typewriters were made the

Hammond typewriters were perfected and made there. Over 1500 men were

finally employed. This shop was very successful both scientifically and

financially. Bergmann was a man of great executive ability and carried

economy of manufacture to the limit. Among all the men I have had

associated with me, he had the commercial instinct most highly

developed."

One need not wonder at Edison's reminiscent remark that, "In any trade

any of my 'boys' made with Bergmann he always got the best of them,

no matter what it was. One time there was to be a convention of the

managers of Edison illuminating companies at Chicago. There were a lot

of representatives from the East, and a private car was hired. At Jersey

City a poker game was started by one of the delegates. Bergmann was

induced to enter the game. This was played right through to Chicago

without any sleep, but the boys didn't mind that. I had gotten them

immune to it. Bergmann had won all the money, and when the porter came

in and said 'Chicago,' Bergmann jumped up and said: 'What! Chicago! I

thought it was only Philadelphia!'"

But perhaps this further story is a better indication of developed humor

and shrewdness: "A man by the name of Epstein had been in the habit

of buying brass chips and trimmings from the lathes, and in some way

Bergmann found out that he had been cheated. This hurt his pride, and

he determined to get even. One day Epstein appeared and said:

'Good-morning, Mr. Bergmann, have you any chips to-day?' 'No,' said

Bergmann, 'I have none.' 'That's strange, Mr. Bergmann; won't you

look?' No, he wouldn't look; he knew he had none. Finally Epstein was so

persistent that Bergmann called an assistant and told him to go and

see if he had any chips. He returned and said they had the largest and

finest lot they ever had. Epstein went up to several boxes piled full of

chips, and so heavy that he could not lift even one end of a box. 'Now,

Mr. Bergmann,' said Epstein, 'how much for the lot?' 'Epstein,' said

Bergmann, 'you have cheated me, and I will no longer sell by the lot,

but will sell only by the pound.' No amount of argument would apparently

change Bergmann's determination to sell by the pound, but finally

Epstein got up to $250 for the lot, and Bergmann, appearing as if

disgusted, accepted and made him count out the money. Then he said:

'Well, Epstein, good-bye, I've got to go down to Wall Street.' Epstein

and his assistant then attempted to lift the boxes to carry them out,

but couldn't; and then discovered that calculations as to quantity had

been thrown out because the boxes had all been screwed down to the floor

and mostly filled with boards with a veneer of brass chips. He made such

a scene that he had to be removed by the police. I met him several days

afterward and he said he had forgiven Mr. Bergmann, as he was such a

smart business man, and the scheme was so ingenious.

"One day as a joke I filled three or four sheets of foolscap paper with

a jumble of figures and told Bergmann they were calculations showing the

great loss of power from blowing the factory whistle. Bergmann thought

it real, and never after that would he permit the whistle to blow."

Another glimpse of the "social side" is afforded in the following little

series of pen-pictures of the same place and time: "I had my laboratory

at the top of the Bergmann works, after moving from Menlo Park. The

building was six stories high. My father came there when he was eighty

years of age. The old man had powerful lungs. In fact, when I was

examined by the Mutual Life Insurance Company, in 1873, my lung

expansion was taken by the doctor, and the old gentleman was there

at the time. He said to the doctor: 'I wish you would take my lung

expansion, too.' The doctor took it, and his surprise was very great,

as it was one of the largest on record. I think it was five and one-half

inches. There were only three or four could beat it. Little Bergmann

hadn't much lung power. The old man said to him, one day: 'Let's run

up-stairs.' Bergmann agreed and ran up. When they got there Bergmann

was all done up, but my father never showed a sign of it. There was an

elevator there, and each day while it was travelling up I held the stem

of my Waterbury watch up against the column in the elevator shaft and

it finished the winding by the time I got up the six stories." This

original method of reducing the amount of physical labor involved in

watch-winding brings to mind another instance of shrewdness mentioned by

Edison, with regard to his newsboy days. Being asked whether he did not

get imposed upon with bad bank-bills, he replied that he subscribed to a

bank-note detector and consulted it closely whenever a note of any size

fell into his hands. He was then less than fourteen years old.

The conversations with Edison that elicited these stories brought out

some details as to peril that attends experimentation. He has confronted

many a serious physical risk, and counts himself lucky to have come

through without a scratch or scar. Four instances of personal danger

may be noted in his own language: "When I started at Menlo, I had an

electric furnace for welding rare metals that I did not know about

very clearly. I was in the dark-room, where I had a lot of chloride of

sulphur, a very corrosive liquid. I did not know that it would decompose

by water. I poured in a beakerful of water, and the whole thing exploded

and threw a lot of it into my eyes. I ran to the hydrant, leaned over

backward, opened my eyes, and ran the hydrant water right into them. But

it was two weeks before I could see.

"The next time we just saved ourselves. I was making some stuff to

squirt into filaments for the incandescent lamp. I made about a pound of

it. I had used ammonia and bromine. I did not know it at the time, but

I had made bromide of nitrogen. I put the large bulk of it in three

filters, and after it had been washed and all the water had come through

the filter, I opened the three filters and laid them on a hot steam

plate to dry with the stuff. While I and Mr. Sadler, one of my

assistants, were working near it, there was a sudden flash of light,

and a very smart explosion. I said to Sadler: 'What is that?' 'I don't

know,' he said, and we paid no attention. In about half a minute there

was a sharp concussion, and Sadler said: 'See, it is that stuff on the

steam plate.' I grabbed the whole thing and threw it in the sink, and

poured water on it. I saved a little of it and found it was a terrific

explosive. The reason why those little preliminary explosions took place

was that a little had spattered out on the edge of the filter paper,

and had dried first and exploded. Had the main body exploded there would

have been nothing left of the laboratory I was working in.

"At another time, I had a briquetting machine for briquetting iron ore.

I had a lever held down by a powerful spring, and a rod one inch in

diameter and four feet long. While I was experimenting with it, and

standing beside it, a washer broke, and that spring threw the rod right

up to the ceiling with a blast; and it came down again just within

an inch of my nose, and went clear through a two-inch plank. That was

'within an inch of your life,' as they say.

"In my experimental plant for concentrating iron ore in the northern

part of New Jersey, we had a vertical drier, a column about nine feet

square and eighty feet high. At the bottom there was a space where two

men could go through a hole; and then all the rest of the column was

filled with baffle plates. One day this drier got blocked, and the ore

would not run down. So I and the vice-president of the company, Mr.

Mallory, crowded through the manhole to see why the ore would not come

down. After we got in, the ore did come down and there were fourteen

tons of it above us. The men outside knew we were in there, and they had

a great time digging us out and getting air to us."

Such incidents brought out in narration the fact that many of the men

working with him had been less fortunate, particularly those who had

experimented with the Roentgen X-ray, whose ravages, like those of

leprosy, were responsible for the mutilation and death of at least one

expert assistant. In the early days of work on the incandescent lamp,

also, there was considerable trouble with mercury. "I had a series of

vacuum-pumps worked by mercury and used for exhausting experimental

incandescent lamps. The main pipe, which was full of mercury, was about

seven and one-half feet from the floor. Along the length of the pipe

were outlets to which thick rubber tubing was connected, each tube to a

pump. One day, while experimenting with the mercury pump, my assistant,

an awkward country lad from a farm on Staten Island, who had adenoids in

his nose and breathed through his mouth, which was always wide open,

was looking up at this pipe, at a small leak of mercury, when the rubber

tube came off and probably two pounds of mercury went into his mouth and

down his throat, and got through his system somehow. In a short time he

became salivated, and his teeth got loose. He went home, and shortly his

mother appeared at the laboratory with a horsewhip, which she proposed

to use on the proprietor. I was fortunately absent, and she was

mollified somehow by my other assistants. I had given the boy

considerable iodide of potassium to prevent salivation, but it did no

good in this case.

"When the first lamp-works were started at Menlo Park, one of my

experiments seemed to show that hot mercury gave a better vacuum in the

lamp than cold mercury. I thereupon started to heat it. Soon all the men

got salivated, and things looked serious; but I found that in the mirror

factories, where mercury was used extensively, the French Government

made the giving of iodide of potassium compulsory to prevent salivation.

I carried out this idea, and made every man take a dose every day, but

there was great opposition, and hot mercury was finally abandoned."

It will have been gathered that Edison has owed his special immunity

from "occupational diseases" not only to luck but to unusual powers of

endurance, and a strong physique, inherited, no doubt, from his father.

Mr. Mallory mentions a little fact that bears on this exceptional

quality of bodily powers. "I have often been surprised at Edison's

wonderful capacity for the instant visual perception of differences in

materials that were invisible to others until he would patiently point

them out. This had puzzled me for years, but one day I was unexpectedly

let into part of the secret. For some little time past Mr. Edison had

noticed that he was bothered somewhat in reading print, and I asked him

to have an oculist give him reading-glasses. He partially promised, but

never took time to attend to it. One day he and I were in the city, and

as Mrs. Edison had spoken to me about it, and as we happened to have

an hour to spare, I persuaded him to go to an oculist with me. Using

no names, I asked the latter to examine the gentleman's eyes. He did so

very conscientiously, and it was an interesting experience, for he was

kept busy answering Mr. Edison's numerous questions. When the oculist

finished, he turned to me and said: 'I have been many years in

the business, but have never seen an optic nerve like that of this

gentleman. An ordinary optic nerve is about the thickness of a thread,

but his is like a cord. He must be a remarkable man in some walk of

life. Who is he?'"

It has certainly required great bodily vigor and physical capacity to

sustain such fatigue as Edison has all his life imposed upon himself,

to the extent on one occasion of going five days without sleep. In a

conversation during 1909, he remarked, as though it were nothing out of

the way, that up to seven years previously his average of daily working

hours was nineteen and one-half, but that since then he figured it

at eighteen. He said he stood it easily, because he was interested in

everything, and was reading and studying all the time. For instance,

he had gone to bed the night before exactly at twelve and had arisen at

4.30 A. M. to read some New York law reports. It was suggested that the

secret of it might be that he did not live in the past, but was always

looking forward to a greater future, to which he replied: "Yes, that's

it. I don't live with the past; I am living for to-day and to-morrow. I

am interested in every department of science, arts, and manufacture.

I read all the time on astronomy, chemistry, biology, physics,

music, metaphysics, mechanics, and other branches--political economy,

electricity, and, in fact, all things that are making for progress in

the world. I get all the proceedings of the scientific societies, the

principal scientific and trade journals, and read them. I also read The

Clipper, The Police Gazette, The Billboard, The Dramatic Mirror, and

a lot of similar publications, for I like to know what is going on. In

this way I keep up to date, and live in a great moving world of my own,

and, what's more, I enjoy every minute of it." Referring to some event

of the past, he said: "Spilt milk doesn't interest me. I have spilt lots

of it, and while I have always felt it for a few days, it is quickly

forgotten, and I turn again to the future." During another talk on

kindred affairs it was suggested to Edison that, as he had worked so

hard all his life, it was about time for him to think somewhat of the

pleasures of travel and the social side of life. To which he replied

laughingly: "I already have a schedule worked out. From now until I am

seventy-five years of age, I expect to keep more or less busy with my

regular work, not, however, working as many hours or as hard as I have

in the past. At seventy five I expect to wear loud waistcoats with

fancy buttons; also gaiter tops; at eighty I expect to learn how to play

bridge whist and talk foolishly to the ladies. At eighty-five I expect

to wear a full-dress suit every evening at dinner, and at ninety--well,

I never plan more than thirty years ahead."

The reference to clothes is interesting, as it is one of the few

subjects in which Edison has no interest. It rather bores him. His dress

is always of the plainest; in fact, so plain that, at the Bergmann shops

in New York, the children attending a parochial Catholic school were

wont to salute him with the finger to the head, every time he went by.

Upon inquiring, he found that they took him for a priest, with his dark

garb, smooth-shaven face, and serious expression. Edison says: "I get

a suit that fits me; then I compel the tailors to use that as a jig or

pattern or blue-print to make others by. For many years a suit was used

as a measurement; once or twice they took fresh measurements, but these

didn't fit and they had to go back. I eat to keep my weight constant,

hence I need never change measurements." In regard to this, Mr. Mallory

furnishes a bit of chat as follows: "In a lawsuit in which I was a

witness, I went out to lunch with the lawyers on both sides, and the

lawyer who had been cross-examining me stated that he had for a client

a Fifth Avenue tailor, who had told him that he had made all of Mr.

Edison's clothes for the last twenty years, and that he had never seen

him. He said that some twenty years ago a suit was sent to him from

Orange, and measurements were made from it, and that every suit since

had been made from these measurements. I may add, from my own personal

observation, that in Mr. Edison's clothes there is no evidence but that

every new suit that he has worn in that time looks as if he had been

specially measured for it, which shows how very little he has changed

physically in the last twenty years."

Edison has never had any taste for amusements, although he will indulge

in the game of "Parchesi" and has a billiard-table in his house. The

coming of the automobile was a great boon to him, because it gave him

a form of outdoor sport in which he could indulge in a spirit of

observation, without the guilty feeling that he was wasting valuable

time. In his automobile he has made long tours, and with his family has

particularly indulged his taste for botany. That he has had the usual

experience in running machines will be evidenced by the following little

story from Mr. Mallory: "About three years ago I had a motor-car of

a make of which Mr. Edison had already two cars; and when the car was

received I made inquiry as to whether any repair parts were carried

by any of the various garages in Easton, Pennsylvania, near our cement

works. I learned that this particular car was the only one in Easton.

Knowing that Mr. Edison had had an experience lasting two or three

years with this particular make of car, I determined to ask him for

information relative to repair parts; so the next time I was at the

laboratory I told him I was unable to get any repair parts in Easton,

and that I wished to order some of the most necessary, so that, in case

of breakdowns, I would not be compelled to lose the use of the car for

several days until the parts came from the automobile factory. I asked

his advice as to what I should order, to which he replied: 'I don't

think it will be necessary to order an extra top.'" Since that episode,

which will probably be appreciated by most automobilists, Edison

has taken up the electric automobile, and is now using it as well as

developing it. One of the cars equipped with his battery is the Bailey,

and Mr. Bee tells the following story in regard to it: "One day Colonel

Bailey, of Amesbury, Massachusetts, who was visiting the Automobile Show

in New York, came out to the laboratory to see Mr. Edison, as the

latter had expressed a desire to talk with him on his next visit to the

metropolis. When he arrived at the laboratory, Mr. Edison, who had been

up all night experimenting, was asleep on the cot in the library. As

a rule we never wake Mr. Edison from sleep, but as he wanted to see

Colonel Bailey, who had to go, I felt that an exception should be made,

so I went and tapped him on the shoulder. He awoke at once, smiling,

jumped up, was instantly himself as usual, and advanced and greeted the

visitor. His very first question was: 'Well, Colonel, how did you come

out on that experiment?'--referring to some suggestions he had made at

their last meeting a year before. For a minute Colonel Bailey did not

recall what was referred to; but a few words from Mr. Edison brought it

back to his remembrance, and he reported that the results had justified

Mr. Edison's expectations."

It might be expected that Edison would have extreme and even radical

ideas on the subject of education--and he has, as well as a perfect

readiness to express them, because he considers that time is wasted on

things that are not essential: "What we need," he has said, "are men

capable of doing work. I wouldn't give a penny for the ordinary college

graduate, except those from the institutes of technology. Those coming

up from the ranks are a darned sight better than the others. They aren't

filled up with Latin, philosophy, and the rest of that ninny stuff." A

further remark of his is: "What the country needs now is the practical

skilled engineer, who is capable of doing everything. In three or four

centuries, when the country is settled, and commercialism is diminished,

there will be time for the literary men. At present we want engineers,

industrial men, good business-like managers, and railroad men." It is

hardly to be marvelled at that such views should elicit warm protest,

summed up in the comment: "Mr. Edison and many like him see in reverse

the course of human progress. Invention does not smooth the way for the

practical men and make them possible. There is always too much danger

of neglecting thoughts for things, ideas for machinery. No theory

of education that aggravates this danger is consistent with national

well-being."

Edison is slow to discuss the great mysteries of life, but is of

reverential attitude of mind, and ever tolerant of others' beliefs. He

is not a religious man in the sense of turning to forms and creeds, but,

as might be expected, is inclined as an inventor and creator to argue

from the basis of "design" and thence to infer a designer. "After years

of watching the processes of nature," he says, "I can no more doubt the

existence of an Intelligence that is running things than I do of the

existence of myself. Take, for example, the substance water that forms

the crystals known as ice. Now, there are hundreds of combinations that

form crystals, and every one of them, save ice, sinks in water. Ice, I

say, doesn't, and it is rather lucky for us mortals, for if it had done

so, we would all be dead. Why? Simply because if ice sank to the bottoms

of rivers, lakes, and oceans as fast as it froze, those places would be

frozen up and there would be no water left. That is only one example

out of thousands that to me prove beyond the possibility of a doubt that

some vast Intelligence is governing this and other planets."

A few words as to the domestic and personal side of Edison's life, to

which many incidental references have already been made in these pages.

He was married in 1873 to Miss Mary Stillwell, who died in 1884, leaving

three children--Thomas Alva, William Leslie, and Marion Estelle.

Mr. Edison was married again in 1886 to Miss Mina Miller, daughter of

Mr. Lewis Miller, a distinguished pioneer inventor and manufacturer in

the field of agricultural machinery, and equally entitled to fame as the

father of the "Chautauqua idea," and the founder with Bishop Vincent

of the original Chautauqua, which now has so many replicas all over the

country, and which started in motion one of the great modern educational

and moral forces in America. By this marriage there are three

children--Charles, Madeline, and Theodore.

For over a score of years, dating from his marriage to Miss Miller,

Edison's happy and perfect domestic life has been spent at Glenmont,

a beautiful property acquired at that time in Llewellyn Park, on the

higher slopes of Orange Mountain, New Jersey, within easy walking

distance of the laboratory at the foot of the hill in West Orange. As

noted already, the latter part of each winter is spent at Fort Myers,

Florida, where Edison has, on the banks of the Calahoutchie River, a

plantation home that is in many ways a miniature copy of the home and

laboratory up North. Glenmont is a rather elaborate and florid building

in Queen Anne English style, of brick, stone, and wooden beams showing

on the exterior, with an abundance of gables and balconies. It is set in

an environment of woods and sweeps of lawn, flanked by unusually large

conservatories, and always bright in summer with glowing flower beds. It

would be difficult to imagine Edison in a stiffly formal house, and this

big, cozy, three-story, rambling mansion has an easy freedom about it,

without and within, quite in keeping with the genius of the inventor,

but revealing at every turn traces of feminine taste and culture. The

ground floor, consisting chiefly of broad drawing-rooms, parlors, and

dining-hall, is chiefly noteworthy for the "den," or lounging-room, at

the end of the main axis, where the family and friends are likely to

be found in the evening hours, unless the party has withdrawn for more

intimate social intercourse to the interesting and fascinating private

library on the floor above. The lounging-room on the ground floor is

more or less of an Edison museum, for it is littered with souvenirs from

great people, and with mementos of travel, all related to some event

or episode. A large cabinet contains awards, decorations, and medals

presented to Edison, accumulating in the course of a long career,

some of which may be seen in the illustration opposite. Near by may be

noticed a bronze replica of the Edison gold medal which was founded in

the American Institute of Electrical Engineers, the first award of which

was made to Elihu Thomson during the present year (1910). There are

statues of serpentine marble, gifts of the late Tsar of Russia, whose

admiration is also represented by a gorgeous inlaid and enamelled

cigar-case.

There are typical bronze vases from the Society of Engineers of Japan,

and a striking desk-set of writing apparatus from Krupp, all the pieces

being made out of tiny but massive guns and shells of Krupp steel. In

addition to such bric-a-brac and bibelots of all kinds are many pictures

and photographs, including the original sketches of the reception given

to Edison in 1889 by the Paris Figaro, and a letter from Madame Carnot,

placing the Presidential opera-box at the disposal of Mr. and Mrs.

Edison. One of the most conspicuous features of the room is a phonograph

equipment on which the latest and best productions by the greatest

singers and musicians can always be heard, but which Edison himself is

everlastingly experimenting with, under the incurable delusion that this

domestic retreat is but an extension of his laboratory.

The big library--semi-boudoir--up-stairs is also very expressive of the

home life of Edison, but again typical of his nature and disposition,

for it is difficult to overlay his many technical books and scientific

periodicals with a sufficiently thick crust of popular magazines or

current literature to prevent their outcropping into evidence. In like

manner the chat and conversation here, however lightly it may begin,

turns invariably to large questions and deep problems, especially in the

fields of discovery and invention; and Edison, in an easy-chair, will

sit through the long evenings till one or two in the morning, pulling

meditatively at his eyebrows, quoting something he has just read

pertinent to the discussion, hearing and telling new stories with gusto,

offering all kinds of ingenious suggestions, and without fail getting

hold of pads and sheets of paper on which to make illustrative sketches.

He is wonderfully handy with the pencil, and will sometimes amuse

himself, while chatting, with making all kinds of fancy bits of

penmanship, twisting his signature into circles and squares, but always

writing straight lines--so straight they could not be ruled truer. Many

a night it is a question of getting Edison to bed, for he would much

rather probe a problem than eat or sleep; but at whatever hour the

visitor retires or gets up, he is sure to find the master of the house

on hand, serene and reposeful, and just as brisk at dawn as when he

allowed the conversation to break up at midnight. The ordinary routine

of daily family life is of course often interrupted by receptions and

parties, visits to the billiard-room, the entertainment of visitors, the

departure to and return from college, at vacation periods, of the young

people, and matters relating to the many social and philanthropic causes

in which Mrs. Edison is actively interested; but, as a matter of fact,

Edison's round of toil and relaxation is singularly uniform and free

from agitation, and that is the way he would rather have it.

Edison at sixty-three has a fine physique, and being free from serious

ailments of any kind, should carry on the traditions of his long-lived

ancestors as to a vigorous old age. His hair has whitened, but is still

thick and abundant, and though he uses glasses for certain work, his

gray-blue eyes are as keen and bright and deeply lustrous as ever, with

the direct, searching look in them that they have ever worn. He

stands five feet nine and one-half inches high, weighs one hundred and

seventy-five pounds, and has not varied as to weight in a quarter of a

century, although as a young man he was slim to gauntness. He is very

abstemious, hardly ever touching alcohol, caring little for meat, but

fond of fruit, and never averse to a strong cup of coffee or a good

cigar. He takes extremely little exercise, although his good color and

quickness of step would suggest to those who do not know better that he

is in the best of training, and one who lives in the open air.

His simplicity as to clothes has already been described. One would be

startled to see him with a bright tie, a loud checked suit, or a fancy

waistcoat, and yet there is a curious sense of fastidiousness about

the plain things he delights in. Perhaps he is not wholly responsible

personally for this state of affairs. In conversation Edison is direct,

courteous, ready to discuss a topic with anybody worth talking to, and,

in spite of his sore deafness, an excellent listener. No one ever goes

away from Edison in doubt as to what he thinks or means, but he is ever

shy and diffident to a degree if the talk turns on himself rather than

on his work.

If the authors were asked, after having written the foregoing pages,

to explain here the reason for Edison's success, based upon their

observations so far made, they would first answer that he combines with

a vigorous and normal physical structure a mind capable of clear and

logical thinking, and an imagination of unusual activity. But this would

by no means offer a complete explanation. There are many men of

equal bodily and mental vigor who have not achieved a tithe of

his accomplishment. What other factors are there to be taken into

consideration to explain this phenomenon? First, a stolid, almost

phlegmatic, nervous system which takes absolutely no notice of ennui--a

system like that of a Chinese ivory-carver who works day after day and

month after month on a piece of material no larger than your hand. No

better illustration of this characteristic can be found than in the

development of the nickel pocket for the storage battery, an element the

size of a short lead-pencil, on which upward of five years were spent

in experiments, costing over a million dollars, day after day, always

apparently with the same tubes but with small variations carefully

tabulated in the note-books. To an ordinary person the mere sight of

such a tube would have been as distasteful, certainly after a week or

so, as the smell of a quail to a man striving to eat one every day for a

month, near the end of his gastronomic ordeal. But to Edison these small

perforated steel tubes held out as much of a fascination at the end of

five years as when the search was first begun, and every morning found

him as eager to begin the investigation anew as if the battery was an

absolutely novel problem to which his thoughts had just been directed.

Another and second characteristic of Edison's personality contributing

so strongly to his achievements is an intense, not to say courageous,

optimism in which no thought of failure can enter, an optimism born of

self-confidence, and becoming--after forty or fifty years of experience

more and more a sense of certainty in the accomplishment of success. In

the overcoming of difficulties he has the same intellectual pleasure

as the chess-master when confronted with a problem requiring all the

efforts of his skill and experience to solve. To advance along smooth

and pleasant paths, to encounter no obstacles, to wrestle with no

difficulties and hardships--such has absolutely no fascination to him.

He meets obstruction with the keen delight of a strong man battling with

the waves and opposing them in sheer enjoyment, and the greater and more

apparently overwhelming the forces that may tend to sweep him back, the

more vigorous his own efforts to forge through them. At the conclusion

of the ore-milling experiments, when practically his entire fortune was

sunk in an enterprise that had to be considered an impossibility, when

at the age of fifty he looked back upon five or six years of intense

activity expended apparently for naught, when everything seemed most

black and the financial clouds were quickly gathering on the horizon,

not the slightest idea of repining entered his mind. The main experiment

had succeeded--he had accomplished what he sought for. Nature at another

point had outstripped him, yet he had broadened his own sum of knowledge

to a prodigious extent. It was only during the past summer (1910) that

one of the writers spent a Sunday with him riding over the beautiful

New Jersey roads in an automobile, Edison in the highest spirits and

pointing out with the keenest enjoyment the many beautiful views of

valley and wood. The wanderings led to the old ore-milling plant at

Edison, now practically a mass of deserted buildings all going to decay.

It was a depressing sight, marking such titanic but futile struggles

with nature. To Edison, however, no trace of sentiment or regret

occurred, and the whole ruins were apparently as much a matter of

unconcern as if he were viewing the remains of Pompeii. Sitting on the

porch of the White House, where he lived during that period, in the

light of the setting sun, his fine face in repose, he looked as placidly

over the scene as a happy farmer over a field of ripening corn. All that

he said was: "I never felt better in my life than during the five years

I worked here. Hard work, nothing to divert my thought, clear air and

simple food made my life very pleasant. We learned a great deal. It will

be of benefit to some one some time." Similarly, in connection with the

storage battery, after having experimented continuously for three years,

it was found to fall below his expectations, and its manufacture had

to be stopped. Hundreds of thousands of dollars had been spent on the

experiments, and, largely without Edison's consent, the battery had been

very generally exploited in the press. To stop meant not only to pocket

a great loss already incurred, facing a dark and uncertain future, but

to most men animated by ordinary human feelings, it meant more than

anything else, an injury to personal pride. Pride? Pooh! that had

nothing to do with the really serious practical problem, and the writers

can testify that at the moment when his decision was reached, work

stopped and the long vista ahead was peered into, Edison was as little

concerned as if he had concluded that, after all, perhaps peach-pie

might be better for present diet than apple-pie. He has often said that

time meant very little to him, that he had but a small realization

of its passage, and that ten or twenty years were as nothing when

considering the development of a vital invention.

These references to personal pride recall another characteristic of

Edison wherein he differs from most men. There are many individuals

who derive an intense and not improper pleasure in regalia or military

garments, with plenty of gold braid and brass buttons, and thus arrayed,

in appearing before their friends and neighbors. Putting at the head of

the procession the man who makes his appeal to public attention solely

because of the brilliancy of his plumage, and passing down the ranks

through the multitudes having a gradually decreasing sense of vanity in

their personal accomplishment, Edison would be placed at the very end.

Reference herein has been made to the fact that one of the two great

English universities wished to confer a degree upon him, but that he

was unable to leave his work for the brief time necessary to accept the

honor. At that occasion it was pointed out to him that he should make

every possible sacrifice to go, that the compliment was great, and that

but few Americans had been so recognized. It was hopeless--an

appeal based on sentiment. Before him was something real--work to be

accomplished--a problem to be solved. Beyond, was a prize as intangible

as the button of the Legion of Honor, which he concealed from his

friends that they might not feel he was "showing off." The fact is that

Edison cares little for the approval of the world, but that he cares

everything for the approval of himself. Difficult as it may be--perhaps

impossible--to trace its origin, Edison possesses what he would probably

call a well-developed case of New England conscience, for whose approval

he is incessantly occupied.

These, then, may be taken as the characteristics of Edison that have

enabled him to accomplish more than most men--a strong body, a clear

and active mind, a developed imagination, a capacity of great mental and

physical concentration, an iron-clad nervous system that knows no ennui,

intense optimism, and courageous self-confidence. Any one having these

capacities developed to the same extent, with the same opportunities for

use, would probably accomplish as much. And yet there is a peculiarity

about him that so far as is known has never been referred to before in

print. He seems to be conscientiously afraid of appearing indolent,

and in consequence subjects himself regularly to unnecessary hardship.

Working all night is seldom necessary, or until two or three o'clock in

the morning, yet even now he persists in such tests upon his strength.

Recently one of the writers had occasion to present to him a long

typewritten document of upward of thirty pages for his approval. It

was taken home to Glenmont. Edison had a few minor corrections to make,

probably not more than a dozen all told. They could have been embodied

by interlineations and marginal notes in the ordinary way, and certainly

would not have required more than ten or fifteen minutes of his time.

Yet what did he do? HE COPIED OUT PAINSTAKINGLY THE ENTIRE PAPER IN

LONG HAND, embodying the corrections as he went along, and presented the

result of his work the following morning. At the very least such a task

must have occupied several hours. How can such a trait--and scores of

similar experiences could be given--be explained except by the fact

that, evidently, he felt the need of special schooling in industry--that

under no circumstances must he allow a thought of indolence to enter his

mind?

Undoubtedly in the days to come Edison will not only be recognized as an

intellectual prodigy, but as a prodigy of industry--of hard work. In his

field as inventor and man of science he stands as clear-cut and secure

as the lighthouse on a rock, and as indifferent to the tumult around.

But as the "old man"--and before he was thirty years old he was

affectionately so called by his laboratory associates--he is a normal,

fun-loving, typical American. His sense of humor is intense, but not

of the hothouse, overdeveloped variety. One of his favorite jokes is to

enter the legal department with an air of great humility and apply for a

job as an inventor! Never is he so preoccupied or fretted with cares as

not to drop all thought of his work for a few moments to listen to a new

story, with a ready smile all the while, and a hearty, boyish laugh at

the end. His laugh, in fact, is sometimes almost aboriginal; slapping

his hands delightedly on his knees, he rocks back and forth and fairly

shouts his pleasure. Recently a daily report of one of his companies

that had just been started contained a large order amounting to several

thousand dollars, and was returned by him with a miniature sketch of a

small individual viewing that particular item through a telescope! His

facility in making hasty but intensely graphic sketches is proverbial.

He takes great delight in imitating the lingo of the New York street

gamin. A dignified person named James may be greeted with: "Hully Gee!

Chimmy, when did youse blow in?" He likes to mimic and imitate types,

generally, that are distasteful to him. The sanctimonious hypocrite, the

sleek speculator, and others whom he has probably encountered in life

are done "to the queen's taste."

One very cold winter's day he entered the laboratory library in fine

spirits, "doing" the decayed dandy, with imaginary cane under his

arm, struggling to put on a pair of tattered imaginary gloves, with

a self-satisfied smirk and leer that would have done credit to a real

comedian. This particular bit of acting was heightened by the fact that

even in the coldest weather he wears thin summer clothes, generally

acid-worn and more or less disreputable. For protection he varies the

number of his suits of underclothing, sometimes wearing three or four

sets, according to the thermometer.

If one could divorce Edison from the idea of work, and could regard

him separate and apart from his embodiment as an inventor and man of

science, it might truly be asserted that his temperament is essentially

mercurial. Often he is in the highest spirits, with all the spontaneity

of youth, and again he is depressed, moody, and violently angry. Anger

with him, however, is a good deal like the story attributed to Napoleon:

"Sire, how is it that your judgment is not affected by your great rage?"

asked one of his courtiers.

"Because," said the Emperor, "I never allow it to rise above this line,"

drawing his hand across his throat. Edison has been seen sometimes

almost beside himself with anger at a stupid mistake or inexcusable

oversight on the part of an assistant, his voice raised to a high pitch,

sneeringly expressing his feelings of contempt for the offender; and yet

when the culprit, like a bad school-boy, has left the room, Edison has

immediately returned to his normal poise, and the incident is a thing

of the past. At other times the unsettled condition persists, and his

spleen is vented not only on the original instigator but upon others who

may have occasion to see him, sometimes hours afterward. When such a

fit is on him the word is quickly passed around, and but few of his

associates find it necessary to consult with him at the time. The

genuine anger can generally be distinguished from the imitation article

by those who know him intimately by the fact that when really enraged

his forehead between the eyes partakes of a curious rotary movement that

cannot be adequately described in words. It is as if the storm-clouds

within are moving like a whirling cyclone. As a general rule, Edison

does not get genuinely angry at mistakes and other human weaknesses of

his subordinates; at best he merely simulates anger. But woe betide the

one who has committed an act of bad faith, treachery, dishonesty, or

ingratitude; THEN Edison can show what it is for a strong man to get

downright mad. But in this respect he is singularly free, and his

spells of anger are really few. In fact, those who know him best are

continually surprised at his moderation and patience, often when there

has been great provocation. People who come in contact with him and who

may have occasion to oppose his views, may leave with the impression

that he is hot-tempered; nothing could be further from the truth. He

argues his point with great vehemence, pounds on the table to emphasize

his views, and illustrates his theme with a wealth of apt similes; but,

on account of his deafness, it is difficult to make the argument really

two-sided. Before the visitor can fully explain his side of the matter

some point is brought up that starts Edison off again, and new arguments

from his viewpoint are poured forth. This constant interruption is taken

by many to mean that Edison has a small opinion of any arguments that

oppose him; but he is only intensely in earnest in presenting his own

side. If the visitor persists until Edison has seen both sides of the

controversy, he is always willing to frankly admit that his own views

may be unsound and that his opponent is right. In fact, after such a

controversy, both parties going after each other hammer and tongs, the

arguments TO HIM being carried on at the very top of one's voice to

enable him to hear, and FROM HIM being equally loud in the excitement

of the discussion, he has often said: "I see now that my position was

absolutely rotten."

Obviously, however, all of these personal characteristics have nothing

to do with Edison's position in the world of affairs. They show him

to be a plain, easy-going, placid American, with no sense of

self-importance, and ready at all times to have his mind turned into a

lighter channel. In private life they show him to be a good citizen, a

good family man, absolutely moral, temperate in all things, and of great

charitableness to all mankind. But what of his position in the age

in which he lives? Where does he rank in the mountain range of great

Americans?

It is believed that from the other chapters of this book the reader can

formulate his own answer to the question.

INTRODUCTION TO THE APPENDIX

THE reader who has followed the foregoing narrative may feel that

inasmuch as it is intended to be an historical document, an appropriate

addendum thereto would be a digest of all the inventions of Edison. The

desirability of such a digest is not to be denied, but as there are some

twenty-five hundred or more inventions to be considered (including those

covered by caveats), the task of its preparation would be stupendous.

Besides, the resultant data would extend this book into several

additional volumes, thereby rendering it of value chiefly to the

technical student, but taking it beyond the bounds of biography.

We should, however, deem our presentation of Mr. Edison's work to

be imperfectly executed if we neglected to include an intelligible

exposition of the broader theoretical principles of his more important

inventions. In the following Appendix we have therefore endeavored

to present a few brief statements regarding Mr. Edison's principal

inventions, classified as to subject-matter and explained in language

as free from technicalities as is possible. No attempt has been made to

conform with strictly scientific terminology, but, for the benefit of

the general reader, well-understood conventional expressions, such as

"flow of current," etc., have been employed. It should be borne in mind

that each of the following items has been treated as a whole or class,

generally speaking, and not as a digest of all the individual patents

relating to it. Any one who is sufficiently interested can obtain copies

of any of the patents referred to for five cents each by addressing the

Commissioner of Patents, Washington, D. C.

APPENDIX

I. THE STOCK PRINTER

IN these modern days, when the Stock Ticker is in universal use, one

seldom, if ever, hears the name of Edison coupled with the little

instrument whose chatterings have such tremendous import to the whole

world. It is of much interest, however, to remember the fact that it

was by reason of his notable work in connection with this device that he

first became known as an inventor. Indeed, it was through the intrinsic

merits of his improvements in stock tickers that he made his real entree

into commercial life.

The idea of the ticker did not originate with Edison, as we have already

seen in Chapter VII of the preceding narrative, but at the time of his

employment with the Western Union, in Boston, in 1868, the crudities of

the earlier forms made an impression on his practical mind, and he got

out an improved instrument of his own, which he introduced in

Boston through the aid of a professional promoter. Edison, then only

twenty-one, had less business experience than the promoter, through

whose manipulation he soon lost his financial interest in this early

ticker enterprise. The narrative tells of his coming to New York in

1869, and immediately plunging into the business of gold and stock

reporting. It was at this period that his real work on stock printers

commenced, first individually, and later as a co-worker with F. L. Pope.

This inventive period extended over a number of years, during which time

he took out forty-six patents on stock-printing instruments and devices,

two of such patents being issued to Edison and Pope as joint inventors.

These various inventions were mostly in the line of development of the

art as it progressed during those early years, but out of it all came

the Edison universal printer, which entered into very extensive use,

and which is still used throughout the United States and in some foreign

countries to a considerable extent at this very day.

Edison's inventive work on stock printers has left its mark upon the art

as it exists at the present time. In his earlier work he directed his

attention to the employment of a single-circuit system, in which only

one wire was required, the two operations of setting the type-wheels

and of printing being controlled by separate electromagnets which were

actuated through polarized relays, as occasion required, one polarity

energizing the electromagnet controlling the type-wheels, and the

opposite polarity energizing the electromagnet controlling the printing.

Later on, however, he changed over to a two-wire circuit, such as

shown in Fig. 2 of this article in connection with the universal stock

printer. In the earliest days of the stock printer, Edison realized

the vital commercial importance of having all instruments recording

precisely alike at the same moment, and it was he who first devised (in

1869) the "unison stop," by means of which all connected instruments

could at any moment be brought to zero from the central transmitting

station, and thus be made to work in correspondence with the central

instrument and with one another. He also originated the idea of using

only one inking-pad and shifting it from side to side to ink the

type-wheels. It was also in Edison's stock printer that the principle of

shifting type-wheels was first employed. Hence it will be seen that,

as in many other arts, he made a lasting impression in this one by the

intrinsic merits of the improvements resulting from his work therein.

We shall not attempt to digest the forty-six patents above named, nor to

follow Edison through the progressive steps which led to the completion

of his universal printer, but shall simply present a sketch of the

instrument itself, and follow with a very brief and general explanation

of its theory. The Edison universal printer, as it virtually appears

in practice, is illustrated in Fig. 1 below, from which it will be seen

that the most prominent parts are the two type-wheels, the inking-pad,

and the paper tape feeding from the reel, all appropriately placed in a

substantial framework.

The electromagnets and other actuating mechanism cannot be seen plainly

in this figure, but are produced diagrammatically in Fig. 2, and

somewhat enlarged for convenience of explanation.

It will be seen that there are two electromagnets, one of which, TM, is

known as the "type-magnet," and the other, PM, as the "press-magnet,"

the former having to do with the operation of the type-wheels, and the

latter with the pressing of the paper tape against them. As will be seen

from the diagram, the armature, A, of the type-magnet has an extension

arm, on the end of which is an escapement engaging with a toothed wheel

placed at the extremity of the shaft carrying the type-wheels. This

extension arm is pivoted at B. Hence, as the armature is alternately

attracted when current passes around its electromagnet, and drawn up by

the spring on cessation of current, it moves up and down, thus actuating

the escapement and causing a rotation of the toothed wheel in the

direction of the arrow. This, in turn, brings any desired letters

or figures on the type-wheels to a central point, where they may be

impressed upon the paper tape. One type-wheel carries letters, and the

other one figures. These two wheels are mounted rigidly on a sleeve

carried by the wheel-shaft. As it is desired to print from only one

type-wheel at a time, it becomes necessary to shift them back and forth

from time to time, in order to bring the desired characters in line

with the paper tape. This is accomplished through the movements of a

three-arm rocking-lever attached to the wheel-sleeve at the end of

the shaft. This lever is actuated through the agency of two small pins

carried by an arm projecting from the press-lever, PL. As the latter

moves up and down the pins play upon the under side of the lower arm of

the rocking-lever, thus canting it and pushing the type-wheels to

the right or left, as the case may be. The operation of shifting the

type-wheels will be given further on.

The press-lever is actuated by the press-magnet. From the diagram

it will be seen that the armature of the latter has a long, pivoted

extension arm, or platen, trough-like in shape, in which the paper tape

runs. It has already been noted that the object of the press-lever is

to press this tape against that character of the type-wheel centrally

located above it at the moment. It will at once be perceived that this

action takes place when current flows through the electromagnet and its

armature is attracted downward, the platen again dropping away from the

type-wheel as the armature is released upon cessation of current. The

paper "feed" is shown at the end of the press-lever, and consists of

a push "dog," or pawl, which operates to urge the paper forward as the

press-lever descends.

The worm-gear which appears in the diagram on the shaft, near the

toothed wheel, forms part of the unison stop above referred to, but this

device is not shown in full, in order to avoid unnecessary complications

of the drawing.

At the right-hand side of the diagram (Fig. 2) is shown a portion of

the transmitting apparatus at a central office. Generally speaking,

this consists of a motor-driven cylinder having metallic pins placed

at intervals, and arranged spirally, around its periphery. These pins

correspond in number to the characters on the type-wheels. A keyboard

(not shown) is arranged above the cylinder, having keys lettered and

numbered corresponding to the letters and figures on the type-wheels.

Upon depressing any one of these keys the motion of the cylinder is

arrested when one of its pins is caught and held by the depressed key.

When the key is released the cylinder continues in motion. Hence, it is

evident that the revolution of the cylinder may be interrupted as often

as desired by manipulation of the various keys in transmitting the

letters and figures which are to be recorded by the printing instrument.

The method of transmission will presently appear.

In the sketch (Fig. 2) there will be seen, mounted upon the cylinder

shaft, two wheels made up of metallic segments insulated from each

other, and upon the hubs of these wheels are two brushes which connect

with the main battery. Resting upon the periphery of these two segmental

wheels there are two brushes to which are connected the wires which

carry the battery current to the type-magnet and press-magnet,

respectively, as the brushes make circuit by coming in contact with the

metallic segments. It will be remembered that upon the cylinder there

are as many pins as there are characters on the type-wheels of the

ticker, and one of the segmental wheels, W, has a like number of

metallic segments, while upon the other wheel, W', there are only

one-half that number. The wheel W controls the supply of current to

the press-magnet, and the wheel W' to the type-magnet. The type-magnet

advances the letter and figure wheels one step when the magnet is

energized, and a succeeding step when the circuit is broken. Hence, the

metallic contact surfaces on wheel W' are, as stated, only half as many

as on the wheel W, which controls the press-magnet.

It should be borne in mind, however, that the contact surfaces and

insulated surfaces on wheel W' are together equal in number to the

characters on the type-wheels, but the retractile spring of TM does half

the work of operating the escapement. On the other hand, the wheel W

has the full number of contact surfaces, because it must provide for the

operative closure of the press-magnet circuit whether the brush B' is in

engagement with a metallic segment or an insulated segment of the wheel

W'. As the cylinder revolves, the wheels are carried around with its

shaft and current impulses flow through the wires to the magnets as the

brushes make contact with the metallic segments of these wheels.

One example will be sufficient to convey to the reader an idea of the

operation of the apparatus. Assuming, for instance, that it is desired

to send out the letters AM to the printer, let us suppose that the pin

corresponding to the letter A is at one end of the cylinder and near the

upper part of its periphery, and that the letter M is about the centre

of the cylinder and near the lower part of its periphery. The operator

at the keyboard would depress the letter A, whereupon the cylinder would

in its revolution bring the first-named pin against the key. During

the rotation of the cylinder a current would pass through wheel W' and

actuate TM, drawing down the armature and operating the escapement,

which would bring the type-wheel to a point where the letter A would

be central as regards the paper tape When the cylinder came to rest,

current would flow through the brush of wheel W to PM, and its armature

would be attracted, causing the platen to be lifted and thus bringing

the paper tape in contact with the type-wheel and printing the letter A.

The operator next sends the letter M by depressing the appropriate key.

On account of the position of the corresponding pin, the cylinder would

make nearly half a revolution before bringing the pin to the key. During

this half revolution the segmental wheels have also been turning, and

the brushes have transmitted a number of current impulses to TM, which

have caused it to operate the escapement a corresponding number of

times, thus turning the type-wheels around to the letter M. When the

cylinder stops, current once more goes to the press-magnet, and the

operation of lifting and printing is repeated. As a matter of fact,

current flows over both circuits as the cylinder is rotated, but the

press-magnet is purposely made to be comparatively "sluggish" and the

narrowness of the segments on wheel W tends to diminish the flow of

current in the press circuit until the cylinder comes to rest, when the

current continuously flows over that circuit without interruption and

fully energizes the press-magnet. The shifting of the type-wheels is

brought about as follows: On the keyboard of the transmitter there are

two characters known as "dots"--namely, the letter dot and the figure

dot. If the operator presses one of these dot keys, it is engaged by an

appropriate pin on the revolving cylinder. Meanwhile the type-wheels are

rotating, carrying with them the rocking-lever, and current is pulsating

over both circuits. When the type-wheels have arrived at the proper

point the rocking-lever has been carried to a position where its lower

arm is directly over one of the pins on the arm extending from the

platen of the press-lever. The cylinder stops, and current operates

the sluggish press-magnet, causing its armature to be attracted, thus

lifting the platen and its projecting arm. As the arm lifts upward, the

pin moves along the under side of the lower arm of the rocking-lever,

thus causing it to cant and shift the type-wheels to the right or left,

as desired. The principles of operation of this apparatus have been

confined to a very brief and general description, but it is believed to

be sufficient for the scope of this article.

NOTE.--The illustrations in this article are reproduced from American

Telegraphy and Encyclopedia of the Telegraph, by William Maver, Jr., by

permission of Maver Publishing Company, New York.

II. THE QUADRUPLEX AND PHONOPLEX

EDISON'S work in stock printers and telegraphy had marked him as a

rising man in the electrical art of the period but his invention of

quadruplex telegraphy in 1874 was what brought him very prominently

before the notice of the public. Duplex telegraphy, or the sending of

two separate messages in opposite directions at the same time over

one line was known and practiced previous to this time, but quadruplex

telegraphy, or the simultaneous sending of four separate messages,

two in each direction, over a single line had not been successfully

accomplished, although it had been the subject of many an inventor's

dream and the object of anxious efforts for many long years.

In the early part of 1873, and for some time afterward, the system

invented by Joseph Stearns was the duplex in practical use. In April of

that year, however, Edison took up the study of the subject and filed

two applications for patents. One of these applications [23] embraced

an invention by which two messages could be sent not only duplex, or

in opposite directions as above explained, but could also be sent

"diplex"--that is to say, in one direction, simultaneously, as separate

and distinct messages, over the one line. Thus there was introduced a

new feature into the art of multiplex telegraphy, for, whereas duplexing

(accomplished by varying the strength of the current) permitted messages

to be sent simultaneously from opposite stations, diplexing (achieved

by also varying the direction of the current) permitted the simultaneous

transmission of two messages from the same station and their separate

reception at the distant station.

[Footnote 23: Afterward issued as Patent No. 162,633, April

27, 1875.]

The quadruplex was the tempting goal toward which Edison now constantly

turned, and after more than a year's strenuous work he filed a number of

applications for patents in the late summer of 1874. Among them was one

which was issued some years afterward as Patent No. 480,567, covering

his well-known quadruplex. He had improved his own diplex, combined it

with the Stearns duplex and thereby produced a system by means of which

four messages could be sent over a single line at the same time, two in

each direction.

As the reader will probably be interested to learn something of the

theoretical principles of this fascinating invention, we shall endeavor

to offer a brief and condensed explanation thereof with as little

technicality as the subject will permit. This explanation will

necessarily be of somewhat elementary character for the benefit of the

lay reader, whose indulgence is asked for an occasional reiteration

introduced for the sake of clearness of comprehension. While the

apparatus and the circuits are seemingly very intricate, the principles

are really quite simple, and the difficulty of comprehension is more

apparent than real if the underlying phenomena are studied attentively.

At the root of all systems of telegraphy, including multiplex systems,

there lies the single basic principle upon which their performance

depends--namely, the obtaining of a slight mechanical movement at the

more or less distant end of a telegraph line. This is accomplished

through the utilization of the phenomena of electromagnetism. These

phenomena are easy of comprehension and demonstration. If a rod of soft

iron be wound around with a number of turns of insulated wire, and

a current of electricity be sent through the wire, the rod will be

instantly magnetized and will remain a magnet as long as the current

flows; but when the current is cut off the magnetic effect instantly

ceases. This device is known as an electromagnet, and the charging and

discharging of such a magnet may, of course, be repeated indefinitely.

Inasmuch as a magnet has the power of attracting to itself pieces of

iron or steel, the basic importance of an electromagnet in telegraphy

will be at once apparent when we consider the sounder, whose clicks

are familiar to every ear. This instrument consists essentially of an

electro-magnet of horseshoe form with its two poles close together, and

with its armature, a bar of iron, maintained in close proximity to the

poles, but kept normally in a retracted position by a spring. When

the distant operator presses down his key the circuit is closed and a

current passes along the line and through the (generally two) coils of

the electromagnet, thus magnetizing the iron core. Its attractive power

draws the armature toward the poles. When the operator releases the

pressure on his key the circuit is broken, current does not flow, the

magnetic effect ceases, and the armature is drawn back by its spring.

These movements give rise to the clicking sounds which represent the

dots and dashes of the Morse or other alphabet as transmitted by the

operator. Similar movements, produced in like manner, are availed of

in another instrument known as the relay, whose office is to act

practically as an automatic transmitter key, repeating the messages

received in its coils, and sending them on to the next section of the

line, equipped with its own battery; or, when the message is intended

for its own station, sending the message to an adjacent sounder included

in a local battery circuit. With a simple circuit, therefore, between

two stations and where an intermediate battery is not necessary, a relay

is not used.

Passing on to the consideration of another phase of the phenomena of

electromagnetism, the reader's attention is called to Fig. 1, in which

will be seen on the left a simple form of electromagnet consisting of

a bar of soft iron wound around with insulated wire, through which a

current is flowing from a battery. The arrows indicate the direction of

flow.

All magnets have two poles, north and south. A permanent magnet (made of

steel, which, as distinguished from soft iron, retains its magnetism for

long periods) is so called because it is permanently magnetized and its

polarity remains fixed. In an electromagnet the magnetism exists only

as long as current is flowing through the wire, and the polarity of the

soft-iron bar is determined by the DIRECTION of flow of current around

it for the time being. If the direction is reversed, the polarity will

also be reversed. Assuming, for instance, the bar to be end-on toward

the observer, that end will be a south pole if the current is flowing

from left to right, clockwise, around the bar; or a north pole if

flowing in the other direction, as illustrated at the right of the

figure. It is immaterial which way the wire is wound around the bar, the

determining factor of polarity being the DIRECTION of the current. It

will be clear, therefore, that if two EQUAL currents be passed around

a bar in opposite directions (Fig. 3) they will tend to produce exactly

opposite polarities and thus neutralize each other. Hence, the bar would

remain non-magnetic.

As the path to the quadruplex passes through the duplex, let us consider

the Stearns system, after noting one other principle--namely, that

if more than one path is presented in which an electric current may

complete its circuit, it divides in proportion to the resistance of each

path. Hence, if we connect one pole of a battery with the earth, and

from the other pole run to the earth two wires of equal resistance as

illustrated in Fig. 2, equal currents will traverse the wires.

The above principles were employed in the Stearns differential duplex

system in the following manner: Referring to Fig. 3, suppose a wire, A,

is led from a battery around a bar of soft iron from left to right, and

another wire of equal resistance and equal number of turns, B, around

from right to left. The flow of current will cause two equal opposing

actions to be set up in the bar; one will exactly offset the other, and

no magnetic effect will be produced. A relay thus wound is known as a

differential relay--more generally called a neutral relay.

The non-technical reader may wonder what use can possibly be made of an

apparently non-operative piece of apparatus. It must be borne in mind,

however, in considering a duplex system, that a differential relay is

used AT EACH END of the line and forms part of the circuit; and that

while each relay must be absolutely unresponsive to the signals SENT

OUT FROM ITS HOME OFFICE, it must respond to signals transmitted by

a DISTANT OFFICE. Hence, the next figure (4), with its accompanying

explanation, will probably make the matter clear. If another battery,

D, be introduced at the distant end of the wire A the differential or

neutral relay becomes actively operative as follows: Battery C supplies

wires A and B with an equal current, but battery D doubles the strength

of the current traversing wire A. This is sufficient to not only

neutralize the magnetism which the current in wire B would tend to set

up, but also--by reason of the excess of current in wire A--to make the

bar a magnet whose polarity would be determined by the direction of the

flow of current around it.

In the arrangement shown in Fig. 4 the batteries are so connected that

current flow is in the same direction, thus doubling the amount of

current flowing through wire A. But suppose the batteries were

so connected that the current from each set flowed in an opposite

direction? The result would be that these currents would oppose and

neutralize each other, and, therefore, none would flow in wire A.

Inasmuch, however, as there is nothing to hinder, current would

flow from battery C through wire B, and the bar would therefore be

magnetized. Hence, assuming that the relay is to be actuated from

the distant end, D, it is in a sense immaterial whether the batteries

connected with wire A assist or oppose each other, as, in either case,

the bar would be magnetized only through the operation of the distant

key.

A slight elaboration of Fig. 4 will further illustrate the principle of

the differential duplex. In Fig. 5 are two stations, A the home end,

and B the distant station to which a message is to be sent. The relay at

each end has two coils, 1 and 2, No. 1 in each case being known as the

"main-line coil" and 2 as the "artificial-line coil." The latter, in

each case, has in its circuit a resistance, R, to compensate for the

resistance of the main line, so that there shall be no inequalities

in the circuits. The artificial line, as well as that to which the two

coils are joined, are connected to earth. There is a battery, C, and a

key, K. When the key is depressed, current flows through the relay

coils at A, but no magnetism is produced, as they oppose each other. The

current, however, flows out through the main-line coil over the line and

through the main-line coil 1 at B, completing its circuit to earth

and magnetizing the bar of the relay, thus causing its armature to be

attracted. On releasing the key the circuit is broken and magnetism

instantly ceases.

It will be evident, therefore, that the operator at A may cause the

relay at B to act without affecting his own relay. Similar effects would

be produced from B to A if the battery and key were placed at the B end.

If, therefore, like instruments are placed at each end of the line, as

in Fig. 6, we have a differential duplex arrangement by means of which

two operators may actuate relays at the ends distant from them, without

causing the operation of the relays at their home ends. In practice

this is done by means of a special instrument known as a continuity

preserving transmitter, or, usually, as a transmitter. This consists

of an electromagnet, T, operated by a key, K, and separate battery. The

armature lever, L, is long, pivoted in the centre, and is bent over

at the end. At a point a little beyond its centre is a small piece of

insulating material to which is screwed a strip of spring metal, S.

Conveniently placed with reference to the end of the lever is a bent

metallic piece, P, having a contact screw in its upper horizontal arm,

and attached to the lower end of this bent piece is a post, or standard,

to which the main battery is electrically connected. The relay coils

are connected by wire to the spring piece, S, and the armature lever is

connected to earth. If the key is depressed, the armature is attracted

and its bent end is moved upward, depressing the spring which makes

contact with the upper screw, which places the battery to the line, and

simultaneously breaks the ground connection between the spring and

the upturned end of the lever, as shown at the left. When the key is

released the battery is again connected to earth. The compensating

resistances and condensers necessary for a duplex arrangement are shown

in the diagram.

In Fig. 6 one transmitter is shown as closed, at A, while the other one

is open. From our previous illustrations and explanations it will be

readily seen that, with the transmitter closed at station A, current

flows via post P, through S, and to both relay coils at A, thence over

the main line to main-line coil at B, and down to earth through S and

the armature lever with its grounded wire. The relay at A would be

unresponsive, but the core of the relay at B would be magnetized and its

armature respond to signals from A. In like manner, if the transmitter

at B be closed, current would flow through similar parts and thus

cause the relay at A to respond. If both transmitters be closed

simultaneously, both batteries will be placed to the line, which would

practically result in doubling the current in each of the main-line

coils, in consequence of which both relays are energized and their

armatures attracted through the operation of the keys at the distant

ends. Hence, two messages can be sent in opposite directions over the

same line simultaneously.

The reader will undoubtedly see quite clearly from the above system,

which rests upon varying the STRENGTH of the current, that two messages

could not be sent in the same direction over the one line at the same

time. To accomplish this object Edison introduced another and distinct

feature--namely, the using of the same current, but ALSO varying its

DIRECTION of flow; that is to say, alternately reversing the POLARITY

of the batteries as applied to the line and thus producing corresponding

changes in the polarity of another specially constructed type of relay,

called a polarized relay. To afford the reader a clear conception of

such a relay we would refer again to Fig. 1 and its explanation, from

which it appears that the polarity of a soft-iron bar is determined not

by the strength of the current flowing around it but by the direction

thereof.

With this idea clearly in mind, the theory of the polarized relay,

generally called "polar" relay, as presented in the diagram (Fig. 7),

will be readily understood.

A is a bar of soft iron, bent as shown, and wound around with insulated

copper wire, the ends of which are connected with a battery, B, thus

forming an electromagnet. An essential part of this relay consists of

a swinging PERMANENT magnet, C, whose polarity remains fixed, that end

between the terminals of the electromagnet being a north pole. Inasmuch

as unlike poles of magnets are attracted to each other and like poles

repelled, it follows that this north pole will be repelled by the north

pole of the electromagnet, but will swing over and be attracted by

its south pole. If the direction of flow of current be reversed, by

reversing the battery, the electromagnetic polarity also reverses and

the end of the permanent magnet swings over to the other side. This

is shown in the two figures of Fig. 7. This device being a relay, its

purpose is to repeat transmitted signals into a local circuit, as before

explained. For this purpose there are provided at D and E a contact and

a back stop, the former of which is opened and closed by the swinging

permanent magnet, thus opening and closing the local circuit.

Manifestly there must be provided some convenient way for rapidly

transposing the direction of the current flow if such a device as the

polar relay is to be used for the reception of telegraph messages, and

this is accomplished by means of an instrument called a pole-changer,

which consists essentially of a movable contact piece connected

permanently to the earth, or grounded, and arranged to connect one or

the other pole of a battery to the line and simultaneously ground the

other pole. This action of the pole-changer is effected by movements of

the armature of an electromagnet through the manipulation of an ordinary

telegraph key by an operator at the home station, as in the operation of

the "transmitter," above referred to.

By a combination of the neutral relay and the polar relay two

operators, by manipulating two telegraph keys in the ordinary way, can

simultaneously send two messages over one line in the SAME direction

with the SAME current, one operator varying its strength and the other

operator varying its polarity or direction of flow. This principle was

covered by Edison's Patent No. 162,633, and was known as the "diplex"

system, although, in the patent referred to, Edison showed and claimed

the adaptation of the principle to duplex telegraphy. Indeed, as

a matter of fact, it was found that by winding the polar relay

differentially and arranging the circuits and collateral appliances

appropriately, the polar duplex system was more highly efficient than

the neutral system, and it is extensively used to the present day.

Thus far we have referred to two systems, one the neutral or

differential duplex, and the other the combination of the neutral and

polar relays, making a diplex system. By one of these two systems

a single wire could be used for sending two messages in opposite

directions, and by the other in the same direction or in opposite

directions. Edison followed up his work on the diplex and combined the

two systems into the quadruplex, by means of which FOUR messages could

be sent and received simultaneously over the one wire, two in each

direction, thus employing eight operators--four at each end--two sending

and two receiving. The general principles of quadruplex telegraphy are

based upon the phenomena which we have briefly outlined in connection

with the neutral relay and the polar relay. The equipment of such

a system at each end of the line consists of these two instruments,

together with the special form of transmitter and the pole-changer and

their keys for actuating the neutral and polar relays at the other, or

distant, end. Besides these there are the compensating resistances and

condensers. All of these will be seen in the diagram (Fig. 8). It

will be understood, of course, that the polar relay, as used in the

quadruplex system, is wound differentially, and therefore its operation

is somewhat similar in principle to that of the differentially wound

neutral relay, in that it does not respond to the operation of the key

at the home office, but only operates in response to the movements of

the distant key.

Our explanation has merely aimed to show the underlying phenomena and

principles in broad outline without entering into more detail than was

deemed absolutely necessary. It should be stated, however, that between

the outline and the filling in of the details there was an enormous

amount of hard work, study, patient plodding, and endless experiments

before Edison finally perfected his quadruplex system in the year 1874.

If it were attempted to offer here a detailed explanation of the varied

and numerous operations of the quadruplex, this article would assume the

proportions of a treatise. An idea of their complexity may be gathered

from the following, which is quoted from American Telegraphy and

Encyclopedia of the Telegraph, by William Maver, Jr.:

"It may well be doubted whether in the whole range of applied

electricity there occur such beautiful combinations, so quickly made,

broken up, and others reformed, as in the operation of the Edison

quadruplex. For example, it is quite demonstrable that during the making

of a simple dash of the Morse alphabet by the neutral relay at the home

station the distant pole-changer may reverse its battery several times;

the home pole-changer may do likewise, and the home transmitter may

increase and decrease the electromotive force of the home battery

repeatedly. Simultaneously, and, of course, as a consequence of the

foregoing actions, the home neutral relay itself may have had its

magnetism reversed several times, and the SIGNAL, that is, the dash,

will have been made, partly by the home battery, partly by the distant

and home batteries combined, partly by current on the main line, partly

by current on the artificial line, partly by the main-line 'static'

current, partly by the condenser static current, and yet, on a

well-adjusted circuit the dash will have been produced on the quadruplex

sounder as clearly as any dash on an ordinary single-wire sounder."