On telephone systems

THE

OF

FRANKLIN INSTITUTE OF THE

FOR

VOL.

THE

STATE

PROMOTION

OF

THE

JANUARY,

CXXI.

THE

OF PENNSYLVANIA,

FRANKLIN

and opinions

ON TELEPHONE

lklii.k~estdunt

subject might

and

PROF. Amos

~hw&~~.s

of the telephone be named,

much attention and has been

but within

I.

for the statements

to the JOURNAL.

SYSTEMS. E. DOLESEAR.

of thr F,KANKLIN.~N~TIT~TE:__T~~~

is not so old as some.other,

in the way the text

No.

responsible

by contributors

HY

ARTS.

I 886.

is not

INSTITUTE

advanced

MECHANIC

su);j&s

that

the past ten years

it has .- engrossed so in all civilized-count-ries,

of experiment

forso.

many

d,iscourses that it is hard

tofind

anything

that shall be new to such a body of. listeners as- I have I cannot hope to add to .your knowledge, and my aim me.

before will therefore be to summarize the principles:. that ur&x-3ie telephony, and the methods that have been adopted in developing it_ I

would

reached, nized, nothing

first

there

remark

are certain

viz., the

laws

accomplished

always

is subject

energy

are

when

physical matter

&y&al’ _z conditions which

and

physical to its own laws, and

such that

WHOLE No. VOL.

of

that

in the

no

transformation

CXXI.-(THIRD

SERIES.

any of

energy.

end is to be must be recogThere can be

Matter world without it. the relations of matter to of the Vol.xci.)

latter

ever

takes I

l7uibenr-

2

place

except

through

the

agency

true to say that the body ments

of the conditions

\Ve under

may call these

spite

of

of

physical

under

which

we live and to which A never be traversed. but on account

of gravity,

1 J. F. I.,

Indeed,

matter. science

it would

is made

energy

be

up of state-

is transformed.

the laws of nature ; they

which

law can

.

are the

conditions

we must conform, for a physical balloon rises in the air not in The

of gravity.

pressure

of steam

is due to molecular impact, and if the molecular velocity be great If the railroad train is to be run fast enough, the boiler bursts. there must ‘be no short curves in ttie road, for Newton’s first law threLrtens disaster Physical ing machine understood when

the

to such a combination.

relations

or laws then are fundamental,

wcbrks in accordance those

latvs or had them

commonly

as the Caloric

with

lleld theory

theory,

them,

in mind

or

of the kinetic

worked

theory

of

gases, and

of heat phenotnena has not affected Clearly then individual intrrztim molecule.

do \vith physical All formers,

devices

transferrers

the chcmism ferrer

laws involved

mechanical

or

in any piece

embodying’

governors.

of coal and oxygen

of heat to

the

water

A furnace into heat. it

a clearer

the motion of a has nothing to

of mechanism.

energy

endowing

is now known

just as it does now,

understanding single

work-

the maker In the days

not.

of heat was what

the steam engine

and the develol~ment

and every

whether

are

either

trans-

is a t~nnsfor~ter

The with

boiler

of

is a ttans-

greater

molecular

The engine is a transformer of the heat energy into visible energy. mechanical rectillinean and rotary motions, while the main shaft is again

a transferrer

of

rotary

energy

to

the

distant

room

where,

through the agency of pulleys and belts the transformations are chiefly such as change the character or direction of motion, converting rotary into reciprocating motion, or ‘i&c-z~i~~‘sa, etc. In like manner

a galvanic

battery

and acids with electrical conducting relay

or

the

electrical

sounder

is a transformer

of the

energy

of zinc

energy.

is again

The leading wires are transferrers, energy where it is needed, while the

a transformer

of

the

electrical

energy

into mechanical motions of an armature which may record its own movements, or the latter may be interpreted at once by an experienced listener. If a Morse key be put in such a circuit, it is as a controller of the transformations, and of course of the transference as well.

It neither

adds to nor subtracts

from the energy,

it simply

controls it.

So long as the Morse key is manipulated by hand, energy available is subject to the will of the operator, only however in its rate of aTeZ&eg, not as to its generation, its the electric

velocity of transmission Those are the physical any intention, and manipulator might

or its transformations in relations which are beyond

could have.

not be

changed

the sounder. the. reach of

by any will

or wish the

It is, however, possible to make an automatic governor or key which shall so contro1 the electricity as to produce a set of signals similar to those made by hand, but this automatic device is built upon physical principles, has its own laws of working, and, wkzZe it is -working, is not subject to any one’s dictation or will or wish. If it does its work properly it is because it is made in accordance with the laws of matter and of energy, which are concerned in its It is as working, whether the maker knew all those laivs or not. true for such a piece of mechanism as for a boiler injector or the governor of a steam engine. These principles or laws are simply adopd, not adapted ; the mechanism is always adapted to the principles or physical laws which are to be operative, and it is right that the distinction between physical laws and the apparatus through which transformations of energy or the control of energy, are possible, should not be lost sight of, for I have known where thestatement of the recognition of a physical law in the sense in which

1 have

physical awarded What,

law it.

described itself.

then,

are

The the

it, has been law

made

has allowed

physical

conditions

as a claim it, and which

upon

the

the court

has

underlie

the

speechelectric transmission of speech ? Speech,-articulate consists of sound vibrations in the air, generally of a highly complex character. The sounds themselves are partIy arbitrary and would partly automatic ; that is, what I call a tree a Frenchman So much is purely call Z’n~bre, and a Chinaman something else. physical difftirence bet ween arbitrary, but there is a difference ,-a my word

tree and your word tree, w.hich no amount of pains taking

on my part could subject to volition

make identical, the character of my voice is not ; it is as automatic as the sound of a violin or of

a cornet, and that for the reason that the instrument that produces it is a physical instrument, having its own laws of vibration and The pitch may he varied, but not the quality, and so resonance.

Lldbcrw

4

it is for a cornet

or a violin.

:

/ 1. k‘. i .,

Articulate

sounds are the arbitrary

ones, and have no particular character like musical instruments, no particular series of harmonics belongs to speech, but articulate sound vibrations by

in air involve

the expenditure

ence

of

such

question

LYZC~‘~~,and can only be maintailrcd

of energy

vibrations

of energy.

and

from

any

one

If the distance

question

point

to

of the

another,

translcr-

is simply. a

be not too great, there ma!. be

enough energy in the vibrations in air to affect the auditory nerve If the souudof a listener, and no transformation will be needed. waves are prevented by a tube from spreading spherically in space, the energy will not be so wasted and the sounds be heard at a greater

distance,

rendered

but there

at a greater

transference

must

the relations,

is a iimit

distance,

be employed.

if any, between

nomena must be employed. electricity quickly distributes that a Morse an electric

key enables

circuit. and variety

a closed door, side of the

and eiectrical

for

they impart

no hand

a

in a similar

The which such sound-waves

phe-

one to send electric pulses at will through to sound vibrations can move

When

portion

way.

wit11 the

sound vibrations

of their

energy

One may whisper

and be heard by one whose

door.

and

We might be supposed to know Ihat itself in a metallic circuit, and also

of sound vibrations.

and cause it to vibrate

is to be

is to be used, then

vibrations

But a key that will respond

fall upon any surface

if speech

for transformation

If electricity

sound

,~tz~t ~ZL~C~SSL~~~~V 6~ autumntic, rapidity

there, and

apparatus

ear is against

to

it,

close to

the other

smaller and thinner the surface against spend themselves, the greater will be the

amplitude

of the

movements.

Let

responding

to any sound vibrat.ion,

such

a

surface,

be provided

capable

with freely

of

moving

electric terminals, so that every vibration shall send into the wire a corresponding electric impulse or wave, and we have a device that will do for speech in an automatic way what the Morse key Gil do when manipulated by hand, namely, vary the strength of an in the

electric

current

chosen

symbols.

mitter, but in reality to control an electric sound-waves.

So

circuit

in accordance

Such a device

is now

it is an automatic curl-ent operated

far as the apparatus

with

certain

arbitrarily

generally called a transgovernor. as its function is by the variable energy oi described

does

what

has

been said, we have an electric circuit in which the electric energy is a variable quantity depending upon the vibratory movements of

Cl?2 Tei+dl~.,?t~~ sj’.sicvllrs.

1886.1

JM.,

the tympanum, the

provided

5

and this may be from the maximum to nothing if permit,

entirely broken. With the R’Iorse key, this range is reached the other,

the range

cannot

be

ting some of the vibrations vibrations

so great

for each signal

without

that constitute If the

produced.

I ,125 feet per second, say, one second,

velocity

and if a sound

then the first wave

between

them

will

danger

the sound.

in the air are a series of continuous

sound is being

wave, and

quantity which the current be

conditions

waves

The

sound

so long

as the

of sound

in air be, say,

of any kind be produced will be I ,125 feet from

be

; with

of omit-

an

unbroken

series

for,

the last

of similar

If such a series had acted upon the terminals of the elecones. tric circuit, the same unbroken series of electric waves would have been produced. WH:\‘r A system

more

or sawn down

either

be

electricity,

or it may be gnawed

If time train

off- by

is to be kept,

may be secured with

attained of action

uniformity

off be

and the

a

is the physical,

some or

are

is not a method

pendulum

to effect

this ; I, therefore,

apparatus

for

such a patent,

time and

keeping if the

be paralleled

by

the

by

celebrated

and

each

in

The end these may

Uniformity for time-keeping, but keeping. had said : I‘ I have kept, it is necessary

and

claim

had

mGve?Hent,

wheel,

or methods.

of time

;” if some

~~z;fovm

different,

movement,

courts

red-hot

or a spring,

early maker of a pendulum clock that in order that time should be mechanical

made

balance

condition

to have a uniform,

would

by

systems

necessary

with an axe,

saw run by steam,

wire

weight

steps

to different

of action

to attain

by beavers.

a pendulum

of gears

be referred

employed

a circular

a platinum

it must

by

is the same, but

properly

If the discovered

a set

?

processes

or by

by hand,

burned

SYSTEM

or

A tree may be cut down

than one way.

or it may

which

A

Some things may be done some purpose. yet there are few things that may not be

some end or accomplish with a single movement, donetin

IS

is a series of steps

I

the

have

invented

method

patent

office

upheld

the

fifth

claim

a

of and the

had

claim, of the

granted the

case

famous

It might be true that no one had telephone patent of 1S76. stated the condition so tersely before, yet the Clepsydra embodied the

proposition

and

astronomers

had

predicted

eclipses

on the

6

fldhi’lli~

basis of unifornl

mot:on

tar time

LJ. I;. I.,

_’

keeping

far

thousands

of >.ears

before. Morse

proposed

a telegraphic

key, a transfttrrinz armature,

whi’ch

wire,

system

consisting

anJ an electro-magnet,

should

record

its

movements.

of a battery, :vith

a movable

Not

one

EIe i uvented neither battery, steps was original with him. nor conducting wire, nor elcctrd-magnet, but he combined such a way as to produce not been

reached

which a batteiy,

valuable

before.

Bain

a

results,

at distances

proposed

a telegraph

of the nor key, these

which

in

had

system,

in

a key, a wire, and an electro-chemical instrument The difNeither of these steps did he invent.

were employed.

ferences were, briefly, that where Morse employed magnetism and its mechanical relations, Kain employed chemism and its optical relations. it.

One embossetl paper, the other made a blue mark upon the diflerences were deeper than this, for the battery-

But

power

needed

to

do

the

work

was

much

less

in

Bain’s

than

in

Morse’s, and, moreover, there is a limit to the speed with which an armature of a magnet can move, and, therefore, a limit to its telegraphic

speed, but there is no such limit to the speed of such chemical

reactions.

Indeed,

the only

ment of Hain’s system these systems,

was its

the electricity

the transmitting

end

had corresponding a similar

motions

of telegraphy, movement

for the abandonIn each of delicacy.

was ‘to it was

of whatever of the

wherein

heard

unnecessary

which

for the work

end, and the movements, system

reason I ever

do work to

do

sort, at the

key.

Then

was fitted

at

at the receiving receiving

end,

there was the Dial

a finger moving

of a finger

about

round a dial caused In each a receiving dial.

and all systems, it was recognized as a physical necessity that if electricity was to do a certain work, it must be fitted for it at the transmitting

station.

If dots

be made at the transmitting as a transferrer, forming

not

property,

the amount

and

dashes

station.

as a transformer,

its efficiency

of energy

are

wanted,

they

The wire is employed and

as a conductor

it can transmit

if it

must simply

has such a trans-

is so much impaired,

in a given

time is less, and

the characteristics of the energy are more or less effaced. It is not, then, singular to the telephone that the characteristics of the energy the electricity the physical

needed

at the condition

at the receiving

transmittina

end, but

that underlies

end should

be given

on the contrary,

all electrical

apparatus

to

it is what-

ever and depends conservation laws must.

solely

tions of mechanical system,

upon

the la\vs of the

transformation

of energy, and must be conformed To give a new crook to a magnet, details

in a transmitter,

is, to me, as ridiculous

some different

color

as it would

and then christen

and

to, as any other or vary the rela-

and call them a new be to paint

it a new thing.

the parts

That

is not

saying but that such changes may be improvements, but so long as the series of changes is precisely the same, from beginning to end,

in both

transmitter

and

receiver,

I do

not

recognize

the

appropriateness of calling anything a new system. A different set of changes, involving different transformations of energy, different laws requiring

different

these must belong

apparatus,

T do call a different

to both transmitter

In conformity

this, what

and

and receiver.

are

the possible

sounds of any sort may be electrically

transmitted

at another

to

system,

ways

by

which

and reproduced

place ?

As to the so-called transmitter, or the device for fitting the electric energy for the work it has to do. There are two ways in (I .)

which electric energy in a given circuit may be controlled. (I) By varying the resistance, and (II), by varying the rlectro-motive force in it. If there be any third way, I do not know of it. If. then, the energy

of sound-waves

can be so utilized

resistance in an electric circuit phases of the sound-waves, we there is to be no transformation,

it is evident

be wholly mechanical, for the sound vibrations mechanical movements in an elastic medium, transformations, the last term the same sense.

as to vary

in conformity with the shall have one method,

of the

the

varying and as

that the action

will

themselves are but and if there be no

series will

be mechanical

in

If sound energy can be made to vary the etectro-motive force in a circuit, without changing the resistance in the circuit, tkLen we The disshall have another and a different kind of transmitter. covery

of magneto-electricity

make

it possible,

and some

of the

very first magneto-electric experiments pointed out the way. namely, the generation of electric cnrrents by means of the motion of the armature of a magnet. (2.) As t 0 receivers. The range of possible receivers is not restricted as is that of transmitters and a great number of ways of utilizing the electrical energy that has been properly adapted by

8 n

i ~oii,Ptri _ transmitter

It will

have been devised.

various effects which electricity (I.) Electricity is competent

1J. b’. I., be well here to recall the

is competent to produce. to affect a magnet, which

set itself at right angles to the wire through which flows. Ordinary galvanometers are constructed to action of- electricity. (II.)

Electricity

is competent

to produce

this property the common electric telegraph other applications have been founded. (III.) Electricity is competent to decompose

a magnet, and

tends

to

the current utilize this and upon

hundreds

compound

of

chemical

substances, as for instance, ivater; and for the utilization of this property of electricity, a common and simple one is the production of a blue mark by means of the decomposition of the ferro-cyanide of potassium as in Bain’s electric telegraph. is competent to deposit one metal upon another (IV.) Electricity up the great industry of metal, and from this property has grown electro-plating. (V.) Electricity

is

competent

to

produce

heat,

the

highest

temperature which man is able to produce at present is that in an electric arc, and is used for the fusion of refractory substances, such as platinum, (VI.) systems

gold

Electricity of electric

by incandescence, direction.

and

steel.

is competent to produce light, lighting, namely, that by the are

developments

of

the

(VII.) Electricity is competent to reduce bodies, and this property has been utilized his telegraphic systems. (VIII.)

Electricity

is competent

at a junction of metals, according that, which is knoivn as I’eltier’s (IX.) Electricity is competent

to produce

and the arc and

possibilities

in

two that that

the friction between by Edison in one of either

heat

or cold

as the current fiows this way or phenomenon. to produce various physiological

effects, and is extensively used as a therapeutic agent. (S ) Electricity is competent to give a tortional strain to a conductor through which it flows, either right handed or left handed, according as the current is towards or away from the This has been used to measure the strength of the observer. current flowing through the wire [ SI.) Elcctrlcity is colnl,
as a kind of galvanometer. to produce I-cry various

gaseous

~l;rll.,

072 TL~~i~ph7EL’ sysfLv7~s.

188h. 1

.phenumena. ,of gaseous

and a visible molecules,

motion

9

of paddle-wheels,

as is exhibited

in various

by the impact

forms of Crooke’s

tubes. (XII.) other

Electricity

is competent

transparent

know,

only

medium,

in the

to twist a ray of light

but

this is at present

investigation

of

physical

in air or

used, so far as I

phenomena

among

molecules. (XIII.)

Electricity

substance, known

called

is competent

ether,

as the electric

phenomena

are

investigation

to

a certain

field,

manifest,

produce

condition,

a field within and which

is competent

disruptive

discharge,

as in the phenomena

on a small scale by electric Electricity

any considerable

will do, which It

available

the subject

of

a noise or sound

of thunder

storms

and Leyden

jars.

produce

attraction,

to

but

by and this

been known perhaps longer than any eIectrica1 kind, has not been utilized to

I have

to

in a teleljhonic

of priority,

arz

other

not enumerated,

is possible

in cotinection

questions

machines

that there

It is not my intention matters

generally interesting

estent.

It is not improbable

effects

to produce

is competent

phenomenon, which has otller of an experimental

citv

is

various

bjr physicists. Electricity

di&overed.

which

which

are at present

(X1V.j

(XV.)

in the non-material

make

things

which

or that will

nearly

every

electri-

hereafter one

be

of these

receiver,

to undertake

any settlement

with the telephone, and the names

nor

which

to

I shall

of historical

enter

upon

employ

to

any de-

s’gnate the different systems I describe, I only adopt for the sake of distinctions which exist, and these can be more easily kept in mind if so individualized, Farrar,

of Keene,

with electro-magilets an electric

circuit,

than in any N. H.,

discovered

and vibrating that

the

other

way. in

185 I, by

reeds that completed

magnet

was

capable

experiments and broke

of responding

IO

i,~,~ihi~trY :

simultaneously

to

seved

tilstinct

[J.

series

of such

F. I.,

reed vibrations,

and that suggested to him that if he could electricity in the circuit by voice vibrations,

contrive to vary the as he did with the speech’ electrically transmit

reed vibrations, that he could He was not able to devise an appropriate couraged sibility

from the attempt of

receiver,

doing

it

by

by the. expressed Prof.

and had proved

transmitter,

Silliman.

its ability

opinion He

and was disof the impos-

had,

however,

the

to act in the way proposed.

I

cannot allude to Farrar’s system as complete,for the work was but half done, and I therefore put in the place of the transmitter the interrogation Nearly mechanism capable

point, to indicate

what was lacking.

ten years after that, that Farrar lacked,

of responding

to

the

Reis, of Germany, invented namely, an apparatus that

minutest

shades

of acoustic

the was

vibra-

tions, and having an automatic attachment making part of an electric circuit, the motions of this attachment, or the electrodes, as it may be called, being governed altogether by the sound-waves in the air.

FIG. 2.

Reis details

made

a number

of transmitters,

in each, but they ali had in common

varying

the

a membrane

mechanical stretched

taut over an aperture, and against which sound-waves of any kind were to impinge. This membrane had fastened to its middte a thin strip or disc of platinum foil, which was connecQd by a wire to a binding post. Connected strip reaching to the middle platinum

wire, fixed at right

to another binding of the membrane,

post was a metal where a piece of

angles, was so adjusted

by a screw as

to touch gently upon the platinum disc and so complete the electric circuit with a battery,and an electro-magnet for a receiver.The energy of the sound-waves was employed to control the electric energy in the circuit, and it was expected that any change in the one would make a corresponding change in the other. That Reis.

I IN

IX66.j

Jan.,

expected

TL~/‘~p/lum

this, is perceived

for compound broken

sound

-one, which,

in his lecture, where

\ribrations if it

in air,

was to

be

made

he gives

the curves

a continuous

transmitted

must not have lost any of its characteristics. intended to have reproduced in his receiver of the sounds

j :

SjJstt’71iS.

at the transmitter.

and

and

nnt a

reproduced,

It is certain that he all the characteristics

He explains

the action

oi

his transmitter as making and breaking the circuit for every vibration of the membrane, and a deal of wearisome talk has been made of late years intention

about Reis’s

to be in the

reproduce

sounds

~%frr&‘uvc,one

function

of the

of all kinds with

point to Reis’s statement the sounds of the piano,

not possibly

apparatus

their

declaring

to

the

transmit

characteristics,

and

and

theJ-

that he thus did transmit and reproduce accordeon, clarionet, horn, organ pipes

and speech. The other party declares make and break the circuit for every could

party

have intentionally

that Keis’s intention was to vibration, and therefore he transmitted

speech

for a con-

tinuous circuit and an undulatory current are essential to do that. If, therefore, Reis did do what he says he did, it was accidentally done, and the

apparatus

It ought

work. named

to be

instruments

same continuousness the transmission of a number

not

remarked,

were

working that

reproduced,

that

is now

as it

if the there

insisted

was

intended

of separate

tones in harmonic

have

on as being

to

which

the for

is made up

series, and continuity

transmit

human

he alluded

as

is

But Reis

speech,

‘I though not with distinctness sufficient for everyone,” if anything that it was distinct enough for some. the lack of distinctness

been

essential

of such sounds as of any other.

says that he was able to

to.

tones of the abovemust

of speech, for the sound of a piano string

as much a characteristic distinctly

was

adding,

which

implies

Reis explains being due to the

fact that the higher overtones were too weak in the receiver for all to hear, not that some of them were not present at all But that objection of a lack of distinctness was brought against the telephone

of the

present

day.

Over

and

over

again,

I have

heard

persons say when first listening to a telephone that was speaking well, that they couldn’t hear what was said, and I dare say everyone has had a similar

experience

who

has worked

with

telephones

to any extent. The fact is, that nearly everyone requires some experience with a telephone before he can make out all that is said, and

Reis’s

audience

.was

not

made

up

of e.xperienced

persons.

12

IAdbetlr

.

\

J. F. I.,

There is, however, no reason at all to doubt that Keis did transmit speech with his apparatus, for, as I ha\-e said before, the working of the transmitter is nr&o~zrrtz’i.,and depends upon the sound-wa\.es that fall upon it, and not upon anyone’s intention of how it shall Take any Reis transmitter and couple it in a circuit do its. work. Now, speak to the with a battery without anything for a receiver. transmitter. Will the sound-waves vary the current strength in a proportional way ? In other words, will the current be the kind known as undulatory, and one capable of reproducing the words spoken? There is only one arlswer to this question ; there are no ifs nor buts about it. Whether,they be heard or not, is another question depending upon the kind of device used for transforming the electric energy, and its degree of sensitivity, also, the acuteIf an electro-magnet ill ness of hearing of the one who listens. adapted to the conditions be used for a receiver, the speech might not be heard, but it would not be because the character of the work of the transmitter was at fault, but because the receiver was not delicate enough. To say otherwise, would be like denying the existence of a current of electricity in a circuit, because the needle of a galvanometer made for strong currents gave no indication of one. If it is of any importance to know whether there be a current or not, include in the circuit the most delicate galvanometer to be had. The test for the character of the working of the Reis transmitter is similar ; put the most delicate receiver at hand in the ci t-cuit and listen. When such a test as that is applied, it is always found that the current from a Reis transmitter is identical with the Where this is one in common use to-day for telephonic purposes. done, however, the deniers of Reis’s claim assert that the transIllitter works on account of knowiedge acquired since 1876, but they kno~v better, and argue thus for commercial reasons only. In~leed, I think it proper to say here that 1 have conferred with a great number of electricians in various parts of the country about this matter, ant\ there is the greatest unanimity concerning it, that Reis did invent a speaking telephone : that he used it fbr that put-pow, and that it works in the same \~a\*~1s tlocs the modern A number have given me testimonials to commer-ciai telepllone. tllat effect, and several r~l~o do not \vish to be mix4 in the contro‘L-he only versy, express privately to me the same views precisely. ones that oppose it are those who have a pecuniary interest in denying it.

J :I

1880.

n ,

Keis’s

system

of

employment

of

to vary

the

resistance

current

in conformity

more of

by

an

are

in which

causing

two

magnet

in

with

magnetic

air

with

sounds

in

the

as in the

resonant

makes

a tolerable

the

all

the

‘l‘he

very

closely

hanging

and,

as

to

main is

source the

resembles be

the

prevent of the

armature,

mounted

of the

might

electro-

to oppose

upon

too,

produces

all

screw

induction This,

the

spring

a stop

side.

to-day.

there,

a

strenqtii,

which other,

these

an arma-

magnetic

the

is

upon

a

a common

armature

and

supposed,

a

the relay

receiver.

Dublin,

in Reis’s

in

other

magnet,

are

side,

magnetic

instrument

spring

electrodes

to

The

recoil

of

with and

of

horizontal

Yates,

provided

on the

due

case;

one

telephone

case.

the

break

poles is

the

Of

case.

rearrangement,

by

is

consists

without

the

the

which

receiver

a resonant

changes

molecular

on the

kIis

so as

transmitter

current,

electro-magnet

current

armature,

this

an

the

the

control

His

circuit.

upon

electrodes, thus

vibrations.

same

reinforced

an

upon

of

in

consists

and

governor

: One

vat-yin:;

attraction

contact

relay,

the

sound

mounted

varieties

operate

electrodes,

the

a corresponding

sound

just

in

electro-magnet,

ture,

to

the

automatic

a battery

there

the

at

J

1-

transmission

vibrations to the

an

sl’,StPIIlS.

telephonic

sound

properly

provided

Tx~ydlUIEt~

UlZ

J

placed

a drop

transmitter,

current

electro-magnet

to which of

the

of

and

water thus

Reis

receiver

was in

a

betxveen

the

prevented

; he also

liable better

platinum

the

way,

nbsokute mounted

ancl

so

g
---‘-) 9

FIG. 3.

better

results.

pupils,

told

me that

and

sulphate

the

same

Yates,

Reis

of

place

which

teaches phonic

Dr.

one

Reis

copper and

for

of

London,

who

was

one

himself

placed

water

and

sulphuric

solution,

and

the

is well

enough

lesson

that

controversy. had

Messel,

actually

has

been been

the

various

purpose.

authenticated

It has achieved

same

other This

for history

overlooked said

electric

over

of

transmission

over

acid

solutions,

in

experiment and

of

credence,

so far in this and

Reis’s

again, of speech,

telethat

if

that

~IodLWLW:

14 everybody

would

have

heard

buried and so little known of the highest importance, Reis’s

speech

of

1J. F. I.,

it, that

it

of it, because and therefore,

could

not

have

been

the achievement was one if so little was known of

transmission,

is not denied

it was because Ire didn”t do it. But it did it in 1866, and that it was known at

that Yates

the time at the University there, but it did not appear to be of enough importance to even chronicIe. Silence, therefore, does not tell against Reis, but against the contemporaries of Reis and Yates. The allied

grandest with business

nothing

without

difference

consists metallic

a diaphragm,

down

into

current

carrying

with

and

armature

worth,

A steam

except

engine

a speaking telephone Of&e early in 1876.

his plan and that

at

liquid. the

so varied in

the

mounted

from

transmitted,

Reis

its

This

solution

wire

for wire

the

middle

and

which

a wire

was

vessel,

I have

for

made

The

part

of the receiver

reaching

an

series of that

reactions

reached

electric

an electro-

by varying

the

from

the

electro-magnet

upon a tube, which was advantageous

for the

of a with

sound made at the in a corresponding

current had

of and

and The

described,

conductor,

a battery

receiver. Any in the solution

strength

liquid.

to the one

same, namely, the resistance

be

is good

for listen-

ing, as the sounds were thereby prevented from scattering degree they did with Reis’s mounting. It did not differ ciple

it

structure of the transmitter, which consisted containing a liquid conductor, the top covered

the

resistance

little

of I Chicago, designed for it in the Patent

magnet with armatrlre diaphragm moved the way,

but

tact and energy.

between

in the vessel,

is of

coal and stoking.

Elisha Gray, entered a caveat only

invention

the

the ear were

to the in prin-

sound practically

to

be the

the air vibrations acting upon an electrode varied of an electric circuit maintained by a battery, and

OH

mep/20YlO

varied

the

_lan., 1886. ] the varying

current

the armature,

causing

magnet’s

it to move

I?3

systetxs.

inductive

in accordance

strength

with

such

upon

current

changes. McDonough, a Reis

also of Chicago,

transmitter

lessening

by

the liability

in structure

to

making

to the

with Reis’s. Drawbaugh,

Bell

departed

the variable

from

armature originating

the

as a system,

is identical

Italian, both

lay

S\'STEiM.

system

already

described.

with the movable

its armature,

being

sound-waves,

proposing

set in, forced

to

vibrations

Beginning

electrodes

and

he placed

speak

to the

similar to the

should react upon the poles of the magnet,

and they upon the coils of wire surrounding that was electrical

an

and in the place of that apparatus

with

itself, which

and

was similar

and Meucci,

he dispensed

resistance,

an electro-magnet

contacts,

receiver

of this system. BELL'S

with the transmitter

His

considered

of Pennsylvania,

claim to the inventions

platinum

disruption.

This,

Gray’s.

about the same time had modified multiple

them, and the current

maintained in them by a galvanic battery, thus causing waves in the circuit corresponding to the sound-waves

FIG.

5.

The receiver was another electro-magnet which produced them. similar to the first,, but so mounted that the vibrations set up there should reach the ear advantageously. SO far as the action at the receiver was concerned, it was similar in all respects to the action in Reis’s receiver, nevertheless the whole is deserving the distinction

of a separate

system,

for

the

receiver

now became

a trans-

mitter,

and thus it had an entirely new function in addition to the Tx?P renzzy nez.?Jthin, r about it was the traizsmitt~~, which old one. acted by setting up electro-motive forces in the circuit, which reacted upon the electro-motive force of the battery, and therefore varied

the strength

of current

in the circuit.

The successive

steps

in this method tions

in the

magnetic

are : Sound

armature

field.

of

The

electro-magnet,

varying

and the

electro-motive

tortes

vibrations

in air causing

the magnet,

varying

field

current

reacts

the upon

of electricity

of a vibratory

the armature

away

The

is one

being

the energy

quite

unlike

the electric

action

the source

the Reis energy

is varied

means

by magnetic

and fro in direction,

changing

while

only,varying

At

the receiver, The

a varying

magnetic

The

changes

which

of

the

degrees

from

testified

in a London

armature

its

it on

testify

what

unpacking, the intention

William,

who

in

of attraction

and vibrates,

impart-

of fact, the form of

Centennial

This

receiver

it home facing

with

was

him.

the

he showed

given

was intended

so the man who I think was. called

to Sir

During of

poles.

forty

transor fifty

Sir William

the receiver

but had not succeeded,

been

of the

electro-magnet, the coil being a disc that fitted

bent up to an angle where

had

in

was not the same

but that the armature

found

Sir

home,

result

exhibition

the

position

Court,

is similar

currents

still bent out of place, that he had endeavored

remember

than

got

proper

talk after his return

the

for the transmitter

who carried

armature

its effects

At

one end of it.

Thomson,

portation,

to

in one

by w’nry&g

strength

As a matter

telephone, the receiver was a cylindrical being within the cylinder, the armature William

vibratory, are all

produces

other

by the

in obedience

air.

employed

upon

is still stronger,

transformations

produced

moves

used for a receiver.

like a cover

by

current

current.

to the adjacent

the electro-magnet

is varied the

really

one the

of

source.

currents

field and a corresponding

upon the armature,

as that

the

of its currents,

the succession

magnetic

ing its energy

other

in strength.

f/k di~rctim by c/znq+g strength of a continuous each.

in tire

a controller

The contrast are

forces

and therefore

transmitter

currents

or

transforma-

of the current

in Bell’s

means directly.

for on the one hand the direction,

while

and

towards

electro-motive

by a separate

the strength

directly,

moved

is simply

the

in it, setting

themselves,

which

is provided

In the ?Ceis transmitter, mechanical

vibrations

transmitter,

which

of

coil

of successive

of all the changing

of the sound

the

present

to whether

from the poles.

vibra-

of the

kind, now in this direction

now in that, according tions of energy,

forced

strength

with the to make

it

and he Eould not

to be bent

up as he

made it was called up to that anyone less eminent as an

expert,

and who

Im.,

On

rX86.j

TrZejMaw2e Syst~~~s.

should give such testimony incompetent. In the same year, nets for both receiver battery,

and have

as that,

would

1876, I proposed and transmitter,

each

instrument

17

be at once

r~dcti

out

as

to employ permarlent magso as to dispense with a

of the

same

fornl.

This

was

FIG. 6.

before I knew anything as to the instruments that Bell had employed, and the first one made was with a straight bar magnet This kind was soon found with the coil wound over only one end. to be much more efficient than the electro-magnet and battery, and was adopted to the exclusion of the other. Considered as a system, however, it differs from Bell’s only in this, that in the latter, the generated currents modified the current permanently in the circuit, while in mine the generated currents were the only ones in the circuit. Several electricians have stated that the two are identical, and that the only object of employing a battery the magnets magnetized, in spite of the well-enough

was to keep known fact

that a magnet may be made stronger by permanent magnetism than by a current on a line of any considerable external resistance, without using an inordinate battery. Somehow I had, for twenty years, the idea of the reciprocal action of magneto-electric devices. I had&ied, in 1855, to make one magneto machine run another one, at-h, failing to do it, wrote to the edltor of the S&e?&& The response was one of A~~erican to know why it didn’t work. two or three lines in the column to correspondents, which answer It 1 have forgotten, for I haven’t seen the number since that time. was marked A. E. D., MO, where I was living at the time. Also, in 1864, I proposed a similar plan for a telegraph, the sender and receiver

to be alike,

and with

similar

functions.

I mention

these

in justice to myself and in order to point out that there was nothing that was new to me in such combination of actions. The system used at present in L~~LZZteCepl’Lorz~/ consists of a transmitter of the Reis pattern, and differing from it only in the substitution of hard carbon where Reis used platinum, while for a WHOLE

No. VOL.

CXXI.--(THIRD

SERIES, Vol. xci.)

3

1J. F. I.,

FIG.

receiver I 876.

is used my straight-bar It is Reis’s

system

7.

permanent

magnet

plus a permanent

magnet.

HERLINER’S

Berliner phone,

proposed

because

His system

a still

consisted

of

SYSTEM.

more

it involved

telephone

novel

principles

plan

for a speaking

unlike

of a transmitter

similar

any

of the

to the Reis’s

teleothers.

in prin-

FIG. 8.

was

ciple, and his receiver two similar instruments battery, varying

were

when an electric

to the transmitter current

to

current

would would

a duplicate

vary

vary

be

of the

put

would

in circuit

traverse

the strength

the

with a suitable

the line.

of the current,

temperature

The

transmitter.

of the

Talking and this

electrodes

at

the receiving instrument enough to develop there what may be called a modified Travellian effect, and produce a sound, the character

of which

trical

energy

would

spent

at the

used as a transmitter, ment had a double upon the convertability doing

work

depend

in moving

upon

terminals.

so that, function. the

diaphragm. by

varying

The

rate of the

receiver

elec-

could then

be

like the Bell system, each instruThe Berliner receiver depended

of electricity

nious plan, and is a system

the

itself,

into

heat, the latter

This

was

as much

at once

a highly

inge-

so as any L could

name. proved

The same principle has been varied somewhat and imupon by others. I, myself, in 1878, used the heating effect of the current in a short wire to work a receiver. Preece,

of

the

in 1880 or 1881,

same

sort ; while

likewise

Cross

has

described lately

some

obtained

experiments surprisingly

On

_latl., 1886.1 good

Tclc/l/‘loze Si,sfefli~*.

results by using a platinum

to the middle

could

my opinion,

six

inches long,

fixed

to of the diaphragm, and a current strong enough He described the effect to be such that red hot.

keep the wire the talking

wire about

I c,,

be heard

several

the transformations

cases, and I therefore

inches

from

of energy

include

them

under

the

are

receiver.

the

the

111

same in these

head

of

Berliner’s

system, EDISON’S

Ten or twelve competent adapted name

years

the discovery

mitter,

between

the

variable the

current

of the

Reis’s

break in the current were

purpose.

Edison

vibrations

parts

mechanical

resistance

and

structure,

It that

to

the

a motophoiie,

soundchanged

It is a takes the place impossible,

collld

and it

fas-

current.

was

his motograph

the

trans-

which

diaphragm

there

make

he gave

of lampblack,

lampblack

transmitter,

great

adapted

the modification

so varied

in which

and

against

of the

was

and, at first,

a telephonic

a mass

transmitter.

in Edison’s

sufficiently then

receiver, invented

traversed

transmitter, in

he

that electricity

two surfaces,

and a diaphragm,

The

of the

resistance

poses, calling

Later,

a solid back

platinum

account

it.

impinge.

the conductivity

discovered

between

to a telegraphic

to

in which

waves could

of

Edison

to lessen the friction

Motograph

tened

ago,

SYSTEM.

the

a

changes

excellent he

in

for

to telephonic when

on

occur

its pur-

then

pos-

FIG. p.

sessed

a telephonic

leaves nothing the

transmitter

receiver

there

system

to be desired. that

vastly

were

which, It

for

loudness

embodied

increased

transformations

its

of performance,

mechanical efficiency,

electrical,

details and

chemical

in

in the and

mechanical, such as had not been even known until his discovery. I am very strongly of the opinion that Edison’s system is one different from anyquite distinct from any other, being radically thing

found in Reis,

or Gray,

or Bell.

UOLBEAK’.-;

In 1878, I devised oneSof could

the

battery

impinge

what

;YSTEM,

I called

plates

was

NO.

a battery

so mounted

I.

transmitter,

upon it and cause it to vibrate.

used for the double

function

of a battery

in which

that the sound-waves In fact, the plate was

element

and

an acoustic

diaphragm, the other element of the battery, zinc, being thick and The cell was thin and small, holding but about a tablerigid. spoonful of dilute acid. When this cell was spoken to, the vibrations of the plate were suf%icient to give the proper characteristics to the current which the cell itself provided, and speech was rendered

in the

ordinary

receiver

with

distinctness

nearly

grsufficient

++ FIG.

for every attraction varying

IO.

I also invented a new receiver combining one.” of a magnet, and the varying friction produced by An

magnetism.

electro-magnet

made

with

the the

a core which

could be rotated on its axis within its coil had resting upon its two poles the two ends of a curved armature, the middle poinuo which was fastened to the middle of a diaphragm. When a current of electricity traversed* the coil, the magnet attracted the armature, holding it snug against the round sides. When now the core was rotated, the adhesion caused the middle of the plate to be bent in or out, as the turning was one way or the other. If the current varied

in strength,

the

magnet

varied

in

strength,

the

adhesion

varied with it, and the armature was thrown into vibrations that corresponded with the current charges, and so speech could be rendered with it. In this it is the varying friction caused by magnetic changes tion as in Reis,

which

is the cause of the sounds, not magnetic

or chemical

dissociation

as in Edison’s,

induc-

while

the

transmitter had the double function of both battery and transmitter, and, therefore, in accordance with my method of distinctions, I rightfully call this a ‘system. .DOLBEAR’S

I once had a receiver tricity

to pass between

SYSTEM,

so made two plates

as to

NO.

2.

permit

a current

with a few drops

of elec.

of ammonium

chloride

between

them

elected

by the

current

would move receiver much

in the expectation would

as the

in principle

dissociative

chemical

the immediate

cause of the sound with

leaked

FIG.

to work

assumed

it necessary

to use the high

get from an induction

of two pIates as perfectly

and had

plainly.

form.

In

a

in as was

one

time, while

between

the plates,

II.

still

from

new phenome-

better

results

a transmitter,

until

I found

force which I could only

as much

insulated

This

For

electro-motive

coil.

which

electricity

At

from

out towards

its present

of the

vibrations.

I still heard the talking

non I at once began

decomposition products

I expected,

relations

this the liquid

the receiver

the

gaseous

from any I have described,

experimenting

when I found

that

in

I found the result

the plates.

still different

result

as the receiver each

other

consisted

as it was

pos-

sible to make them both by a thin layer of air and by thick varnishing, the resistance was practically infinite, and no current could it ; therefore

traverse

a transmitter

which must be maintained, coil is an essential consists of the

variable

being

an induction

coil of high

nals of

coil

the ordinary constitute

its commercial in two ways:

connected The

working,

by which

used platinum,

structure

of

the

of the receiver

for it adds to the capacity

it becomes

combined

with

3,000 ohms or more, the termireceiver

by

is such as to

but in addition to that the varnishing important part, an essential part in

s an ordinary

is then like a charged

transmitter

of the plan of Reis,

with the two plates

prays a very

(r.)A

Reis

An induction

The complete

transmitter

resistance,

it an air condenser,

upon the plates

property

resistant

used where

line wire.

only vary a current

was out of the question.

part of the apparatus.

hard carbon this

such as could

dielectric,

electrified,

electroscope

of the condenser

and (2.) in its absorptive retaining

or electrometer,

its charge. and

It

is much

than when lectric different

from

the

the plates are simply metallic and incaIn operation this system is radically action.

others,

for (I .) it is not

operated

by a current.

22

The

opposed

each

other.

plates are

One at its middle

other

oppositely

law

has no application

line is entirely tricity and tricity

phenomena.

static

accumulates the shore. likened

The

measurements various

magneto

the

it comes

line, therefore,

telephone

may

have

strength

reports

satne as in the common

condition.

for magneto

condition,

from the outset must

and the character

will

be

placed

net

to vary

of

are line

work

in it just the

in same

my

receiver,

the current,

necessarily

and if

to vary. unlike

is in a different

the transformations

to be found in the others, it is a system

If two receivers

who have declared

there can be nothing

and receiver

with

current

(3.) High electro-motive lines. A battery and a transmitter,

of the transmitter

the others, and as the transferring

while

river with has made

in telephones

employed

there were currents

purposes,

evidently

As both transmitter

condition

that there was no measurable

telephone

essential

there be no current

and it

of level,

may be likened to an unobstructed of water flowing. Prof. Cross who

of the current

for it is the function

elec-

beyond,

barrier

its electrical change

But there have been some electricians

good

the

the coil to the ground to an impassible

a continuous

that so far as the line was concerned

however

body,

In

in my line, which is just what I have maintained

force is another

g charged

it piles up, so to speak, as the tide does against

transmitters,

be the case.

of the

place in it are of the nature of

to an ocean tide and

the magneto line variable quantities

condition

taking through

telephone there,

attract

lines, for as no elec-

it, the line itself becomes

changes

goes uninterruptedly

the

electrical

(2.) The

from that in the other

can flow through

electro-static

and therefore

but no current traverses the receiver by thousands of megohms and ohms

to it.

different

any electrical

charged,

of them is free to move slightly towards the point, the strength of the attraction determin-

ing the amount of movement, for its resistance is measured

In

[J. F. I.,

/)&war:

any

of

electrical

of energy

not

by itself.

circuit

uncharged,

if one

On

J:ln., r886.j

TeZephme

S+.rtems.

23

attempts to use the arrangement for the transmission of speech he will fail, for merely vibrating one plate near another will not generate an electrical

phenomenon,

but if the

way, one may then use each instrument In this way I have

worked

the most ordinary

(4.) current duced

the finger

that

if an

in contact

with

on the line would by sound

vibrations

resistance transmittter. receiver

moistened

with

or receiver.

electric the

years,

experiment

with the frog’s

never leg

I never

prepared

completed the

gravity cells and the end of The efficient transmitter. this transmitter to make every

done

that

in circuit summer

is for

it.

has

witnessed leg

was

of a tin cup,

by the change in pressure procup, so that it was a variable

represented

but have

circuit

bottom

I have threatened

six or eight

ment, yet I confess

13.

be varied in the

I have

which

that the properly

in any

over a half mile of line with

With a dozen is a tolerably

it

which

an ideal receiver

charged

insulation.

In 1878 I found

the finger

be

as transmitter

successfully

FIG.

though

line

Ever since Galvani’s been a standard experiIt is said

the phenomenon.

of a frog

is a particularly

delicate

electroscope,

and that it only requires the contact of a piece of I therefore prozinc and copper to throw the leg into spasms. posed to connect such a leg with the plate of a telephone, completing the circuit through that the changing movements

the leg, a battery

currents

of the frog’s

plate, in which

would

leg

which

case the diagram

is but-one

other

complete

expecting

cause

corresponding

would

be communicated

represents

BKEGUET

There

and a transmitter,

still another

muscular to the

system.

SYSTEM.

system

that I chance

to know

of, and that is Hreguet’s. 1,ippmann made the discovery that the surface of mercury was visibly deformed by a current of electricity upon it from the point, and Hreguet reduced this to telephonic purTransmitter and receiver are both alike and have similar poses.

functioils.

A glass vessel contains some mercury with some acidulated water upon it. A small glass tube drawn to a point but not closed, is also filled with mercury and properly supported above, so that the point of the tube should be quite near the surface of the mercury. ‘Ihe mercury in both cup and tube must be provided with external corn pleted. either tube

may

be

When these two are connected thus, any motion towards or away from the surface will be followed

metallic

connections

that an electric

of by

a corresponding motion of the other. There are several telephone inventions

circuit

of importance,

and some

of them of the highest, that are in the nature of improvements. Transmitters and receivers have both been made more efficient by their use, while some have only a scientific A few of these I shall notice. Among

transmitters

embodying

name the thermo-eIectric-pile. meeting of the American Science, an experiment Sound into Electricity,”

and theoretical

diKerence

interest.

in principle

I would

In 1873 I described at the Portland Association for the Advancement of

I had made “ On the in which the vibration

Convertability of a tuning

of fork

upon the face of a thermo-pile had developed electricity. At the time the criticism on the paper was that the vibration resulted in heat, which

was the cause of the phenomenon,

FIG. 15.

As

soon as the magneto

coupled

it

fork

before,

as

in circuit and

with at

once

telephone

was

a thermo-pile heard

the

available and

applied

pitch

of the

for the test

I

the tuning fork

at the

receiver,

and

:hat,

thermo-pile.

I

with a therm0 but about expected.

too, at

have

the

also

transmitter. of

-0001

a volt,

As contrasted

half an inch long,

and with

is at the other

possibly through

blown

the

out

half

such

a mife

from

the

in

the

density

vary

nothing currents

much

can be

an electric

arc,

extreme.

sensitive

with

changes

an arc would

of

with such weak

As the arc is exceedingly arc may be

distance

heard the voice, but only very weakly, The electro-motive forces are at best

to

air

currents,

breath,

it

in

vibrations

air

the current

occurred

strength

and to

as an

me that

made

enough

to

to

go

enable

FIG. 16.

sounds to be reproduced arc by a speaking or three through

inches

terminals

away

the primary

be injured

by it.

tube, every

by such

from

wire

The

word

sounds ?iFre spoken

the

of the secondary

of

directed

to the

the sparks

two

arc.

of a large

a current

driving

The current was passed induction coil that could not

fifteen

connected

or

twenty

alternately

amp&es.

with

The

the magneto

Only the faintest show of a sound could and the static receivers. I did, however, hear some sounds, but not speech. be heard. Whistling .

was plainest.

I discovered

as bearing the most

one thing

upon future sudden

break

times less sonorous

of such

effect

from a single Leclanch6. is that it is impossible the telephone,

so

ordinary

of

effect

ceived, but their not possible

of interest

to produce the

ear

magnetization gradualness

to get a spark

a current

an hundred than the break

give.

The explanation probable a sudden enough break to effect could

perceive

it.

Not

and demagnetization

prevents

long

too,

; that is, that

produced telephone

an acoustic

of any appreciable

though

spark four or five inches

in transmitters

in the receiving

cell would

that

ing of such a current,

and of some importance,

improvements

with half was easily

length

a dozen obtained.

that the

are not effect.

It

perwas

by the break-

bichromate As

cells a

it has been

26 found

by

experience

tllat

electro-motive

an

force

three or four volts in the primary circuit transmitter of that kind was not so efficient be explained

that

the terminals

of such transmitters

within

the

slight

be an arc the current considerable electro-motive volts,

than

distances,

to which

the formation

to the performance,

is not varied,

it continues

of an

for if there

right

on with

no

diminution. It is, therefore, necessary to use a lower force, and that from two Leclanche cells, say three

is as much as can ever

Elisha Gray discovered enon a good many years tension

currents

passed

metallic

surface

that there

the metal

movable

are subject,

arc across the space is detrimental

greater

with a Blake or other as less. I take it to

gave

of the circuit.

be employed

with

such transmitters.

a curious electro-physiological phenomago, namely, that when vibratory high through

a finger

was an apparent

contact

upon a movable

increased

adhesion,

and

out a sound whiclr was the pitch of the interruption This

he modified

into a telephonic

receiver.

The

phenomenon is curious when compared with that of the motophone of Edison; for in the latter the friction is lessened by the current, while

in the former

it is increased.

Lastly, there are three but novelty to recommend know

telephonic receivers, which have them, but I thought you might

nothing like to

of them.

FIG.

(1.1 An

incandescent

a speech

receiver.

I)erforms

better

to low

redness.

The

when I

17.

electric

lam-p of the

current

needs

the current

suppose

it

ordinary

to be a strong

is sufficient

to heat

is to be explained

impacts

held against

are against

the

by what

described under the head of Berliner’s system. (2 > Crooke’s tubes may be similarly employed, By using one resistance induction coil is needed. gaseous

sort makes one, and

it

filament 1 have

only a high in which the

the side of the tube, or bulb, and that

the ear, one may hear the spoken

words.

Jan.,

I 886.1

FIG. 18.

,(3.] A Leyd en J‘ar of the ordinary ing the outer coatings

coating

being

while

pattern

the knob

the terminals

held, one hand grasp-

is placed

of a secondary

in the

from

ear, the two

almost

any kind

of a transmitter.

FIG. 19.

It tivity

was Hughes,

of England,

of hard carbon

who

and pointed

discovered

the

great

out its adaptability

sensi-

to telephonic

A discovery of such importance, that if he had seen fit purposes. to patent, as he might have done, he would have practically controlled

the telephone

-of Great

Britain

distinctions.

It

for commercial has

has been claimed

the use of plumbago own hard carbon

and

properties

very much because would required

starch some better,

by those for

could and

discover

if the

he first

described

be similar.

Yet

but an infinitesimal

first

that

should

an amylose

I heard

of the atoms

If

for the

Sir William

amount

useful

then

purpose, wouId

claim purpose,

Thomson

of invention

It is the properties

one should

cotton

of

and arrange-

and the molecular gas coke.

to

also

to be compared

constitution

be used for a certain

should

other

they

that is named carbon.

and

Society

who own the right

such uses that

are no more

that are wanted,

one

for

are not the properties

are not the same in lampblack that

among

upon the molecular It is the atom

ment of the body.

cover

Royal

this

of any sort, but they

the body, but depend

afterwards

The

him

lampblack

than peet and anthracite. The properties of a body

molecular

purposes.

honored

just

disand

answer

the cotton the cases say that it

to substitute

gas

28 coke

/)c)ilKnv : for

lampblack,

to him. The

Blake

and

\ve all

transmitter

[J. F. I.,

know

consists

what

simply

infinitesimal in

the

means

adoption

of

Hughes’ hard carbon for the platinum in Reis’s transmitter. It makes it much more efficient, but does not change its mode of opetxtion nor vary the mechanical relations. Hunning, an English clergyman, has made a very useful transmitter by employine b granulated hard carbon, arranged mechanically in the circuit with this transmitter

as Edison arranged his carbon button, the best long line work has been done.

a11d

In conclusion, I do not pretend to say who was the first inventor but I think I have made it plain that there of an art of telephony, are several arts of telephony that are complete in themselves, just as there are several arts of picture painting. One man paints with a brush, another

with a roller

and

a press.

When

the

pictures

are done, no one can tell, by inspection, which way either was made, hence it is improper to speak of t/zr art of picture making_ Leaving out all that \?ras done before 1876, I submit that the work of that year ought not to control systems that have been invented and discovered in their entirety since that time, and have aImost nothing

in common

law which

equity

has

which

been

113s been

name of science, justice, after

herself every

inco~upjnefenf.

lvith

whose

a judge,

signature

it.

misjudged

1 protest

against

; 1 protest

scandalized

eyes are the court

; and I protest not

bandaged

of highest

to a judgment _ ._-._

__

it

against

in the

of of

against

it in the

as are the eyes of

appeal,

in her

name

it in the name

and who writes

court,

co?+@efexf

or

_____ ~___~

GENESIS OF CHoLmca.-In a recent sitting of the French Academy of Medicine, Professor Peter expressed the opinion that European and Indian cholera differ only by the relative morbific intensity of the producing causes. The two forms may arise spontaneously, either in Europe or in India, being engendered in either case by volatile ptomaines produced by organic putrefaction. M. Gustave Le Bon reports some interesting obser\ratioms, made during his visits to India, which strikingly corroborate these views. The cholera in India is confined almost exclusively to the Hindoo population. Even in the great cities all the English live in cantonments, which are reThe. served for their exclusive use, at some kilometres from the towns. hygienic arrangements are very complete ; neatness is pushed to excess, and the most scrupulous attention is paid to the origin of the water which is used. -COV~@S Rendus, .Ce$+. zz, zS8_y.