Edison, His Life and Inventions

F >> Frank Lewis Dyer and Thomas Commerford Martin >> Edison, His Life and Inventions


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.