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.. L i v

FROM THE LIBRARY OF
DR. CHARLES SINGER

^> ^

7
1'

MEDALLION AND AUTOGRAPH
FKOM MONUMENT TO PHIL1IT REIS AT FRIEDRICHSDORF.

PHILIPP REIS;

INVENTOR OF

THE TELEPHONE

A BIOGKAPHICAL SKETCH,

WITH DOCUMENTARY TESTIMONY, TRANSLATIONS OF THE

ORIGINAL PAPERS OF THE INVENTOR AND

CONTEMPORARY PUBLICATIONS.

SILVANUS P. THOMPSON, B.A., D.Sc.,

PROFESSOR OF EXPERIMENTAL PHYSICS IN UNIVERSITY COLLEGE, BRISTOL.

LONDON:

E. & F. K SPON, 16, CHAEING CEOSS.
NEW YORK: 35, MURRAY STREET.

1883.

Tt+Ts

PREFACE.

THE title of this little work sufficiently indicates its nature
and scope. The labour of preparing it has not been slight,
and has involved the expenditure of much time in prose-
cuting inquiries both in this country and in Germany
amongst the surviving contemporaries of Philipp Eeis. To
set forth the history of this long-neglected inventor and of
his instrument, and to establish upon its own merits, without
special pleading, and without partiality, the nature of that
much-misunderstood and much-abused invention, has been
the aim of the writer. The thought that he might thus be of
service in rendering justice to the memory of the departed
worthy has inspired him to his task. He has nothing to
gain by making Eeis's invention appear either better or
worse than it really was. He has therefore preferred to let
the contemporary documents and the testimony of eye-
witnesses speak for themselves, and has added that which
seemed to him desirable in the way of argument in the form
of four appendices.

The author's acknowledgments are due in an especial
manner to Mr. Albert Stetson, A.M., of Cohasset, Massa-
chusetts, who has given him much valuable assistance in the
collection of information both in Germany and in this
country, and who has also assisted in the translation of some

590

PREFACE.

of the contemporary documents to be found in the work.
To the friends, acquaintances, and pupils of Philipp Eeis,
and especially to the surviving members of the family at
Friedrichsdorf, who have most kindly furnished many de-
tails of information, the author would express his most
cordial thanks. The testimony now adduced as to the aim
of Philipp Eeis's invention, and the measure of success which
he himself attained, is such, in the author's opinion, and in
the opinion, he trusts, of all right-thinking persons, to place
beyond cavil the rightfulness of the claim which Eeis him-
self put forward of being the inventor of the Telephone.
Full and sufficient as that testimony is, much more remains
as yet unpublished. The author has, for example, been
permitted to examine a mass of evidence collected by the
Dolbear Telephone Company, which entirely corroborates
that which is here presented. It is, however, for certain
reasons beyond the author's control, deemed well at the
present moment to withhold this testimony for a little while
from publication. The appearance of this volume at the
present time needs no apology from the author. He is
conscious that all he can do will add little or nothing to
the lustre with which the name of Philipp Eeis will be
handed down to posterity. When the Jubilee of Philipp
Eeis comes to be celebrated in 1884 (January 7th), the
world will find out its indebtedness to the great man whose
thoughts survive him.

CONTENTS.

PAGE

PREFACE ...... . . . v

LIST OF ILLUSTRATIONS . viii

I BIOGRAPHY OF THE INVENTOR ...... 1

II. THE INVENTOR'S APPARATUS . . . . .14

(a) Transmitters.
(5) Receivers.

III. THE CLAIM OF THE INVENTOR ...... 35

IV. CONTEMPORARY DOCUMENTS ...... 50

V. TESTIMONY OF CONTEMPORARY WITNESSES .... 112

APPENDIX

I. COMPARISON OF REIS'S TRANSMITTERS WITH RECENT INSTRU-
MENTS ......... 131

II. ON THE VARIATION OF ELECTRIC RESISTANCE AT A POINT OF

IMPERFECT CONTACT IN A CIRCUIT .... 143

III. COMPARISON OF REIS'S RECEIVERS WITH RECENT INSTRUMENTS 154

IV. ON THE DOCTRINE OF UNDULATORY CURRENTS . . .165
SCHEDULE OF AUTHORITIES AND REFERENCES .... 180
ADDITIONAL REFERENCES CONCERNING REIS'S TELEPHONE 182

LIST OP ILLUSTRATIONS.

PAGE

Medallion-portrait of the Inventor (from the Medallion executed
FIG. by Kumpf in 1878), and Autograph. . . Frontispiece

1. Vignette. Tomb of Philipp Reis, at Friedrichsdorf . . 13

2. First Transmitter (the Wooden Ear) — back view ... 16

3. „ „ „ front „ . . .1C

4. „ „ „ side „ . .16

5. „ „ „ section,, ... 16

6. „ „ „ details . . . 17

7. Second Transmitter (Tin Tube) 19

8. Third Transmitter (Collar-box) 19

9. Fourth Transmitter (Bored Block) 20

10. „ „ „ section ... 21

11. Sixth Transmitter (Wooden Cone) 22

12. Eeis's Photograph of himself, holding his Telephone (Seventh

Form) in his Hand 23

13. Seventh Transmitter (" Hochstift " Form) .... 24

14. Eighth Transmitter (Lever Form) 25

15. Ninth Transmitter (Transitional Form) .... 26

16. „ „ „ „ section . 26

17. Tenth Transmitter (Square Box) 27

18. „ „ „ opened .... 27

19. First Receiver (Violin Form) . . . . . .29

20. Second Receiver (Cigar-box) ...... 30

21. Third Receiver (Electromagnet) 32

22. Fourth Receiver (Knitting-needle) 33

23. „ „ „ ..... 33

24. Curve of Condensation and Rarefaction in Sound-wave . . 53

25. Telephone ("Bored Block") shown to Physical Society of

Frankfort-on-the-Main . . 55

LIST OF ILLUSTRATIONS. ix

FIG. PAGE

26. Sound Curves 58

27. „ „ 59

28. Facsimile sketch from Reis's Letter to Mr. Ladd ... 83

29. The Telephone (from Reis's Prospectus) .... 86

30. „ „ (from Miiller-Poiallet's Physics) ... 97

31. Details of Transmitter ( „ „ ) . . . 97

32. Receiver ( „ „ ) . . . 97

33. The Telephone (from Pisko's Acoustics) . . . .100

34. „ „ (from Kuhn's Handbook) .... 109

35. Cone used in Transmitter ........ 117

36. Metal Tympanum 117

37. Second Receiver (Cigar-box) 118

38. Receiver with Lid 118

39. Projected form of Receiver with Electromagnet . . .119

40. „ „ „ . 119

41. Sketch of Experimental Transmitter ..... 122

42. Yeates' Receiver for Reis's Telephone 128

43. Berliner's Transmitter 136

44. Blake's Transmitter 137

45. Comparative Series of Transmitters ..... 139

46. Comparative Series of Receivers ...... 157

47. Curves from Reis's Memoir " On Telephony " . . .173

48. Curves from Bell's Specification (U.S. Patent) . . .173

PLATE

I. Curves from Yon Legat's Report on Reis's Telephone.
II. Reis's Telephone, from Yon Legat's Report.

PHILIPP EEIS.

CHAPTEK I.

BIOGRAPHY OF THE INVENTOR.

[Compiled chiefly from papers left by the deceased, and from the bio-
graphical notice of the late Professor Schenk.]

PHILIPP EEIS, or, as his full name appears from his auto-
biographical sketch to have been, Johann Philipp Eeis, was
born on the 7th of January, 1834, at Gelnhausen, in the
principality of Cassel. His father, who belonged to the
Evangelical Church, was a master baker, but also pursued
farming to some extent, as the circumstances of small
provincial towns generally require. As his mother had died
young, his paternal grandmother undertook the bringing up
of the boy. " While my father," writes Herr Eeis, " strove
constantly to cultivate my mental powers by instruction
concerning the things which surrounded me (by discussing
that which was actually observed), my grandmother turned
her activity to training my disposition and to the develop-
ment of the religious sentiments to which she was eminently
fitted by the experiences of a long life, by being well-read,
and especially by her gift of narration."

On attaining his sixth year the boy was sent to the
common school of his native town. His teachers soon re-
cognised that he possessed no ordinary endowments, and

PEILIPP BEIS,

sought to induce his father to entrust him later to a higher
institution of learning. His father agreed to this ; and the
plan was to have been carried out after the boy had passed
the middle-class of the common school. How the father
contemplated the carrying out of the plan is not known ;
he died ere the son had yet completed his tenth year.

As a considerable number of children from Frankfort-
on-the-Main and its neighbourhood, attended that time
Garnier's Institute at Friedrichsdorf, near Homburg, the
idea occurred to his guardian and his grandmother to
entrust the boy to this school. He entered there when in
his eleventh year. " The foreign languages, English and
French, taught in the Institute, attracted me specially. The
library of the Institute, rich and well chosen for its size, gave
my mind excellent nourishment." At the end of his four-
teenth year he had passed through the school, organised as
it then was, and he now went to Hassel's Institute at
Frankfort-on-the-Main. His delight in the study of language
induced him to learn Latin and Italian. And here, also,
the taste for the study of natural sciences and mathematics
appears to have been awakened in him. The lively zeal with
which he applied himself to both these disciplines induced
his teachers to advise his guardian that he should allow the
boy to attend the Polytechnic School at Carlsruhe, on
finishing his course at the Institute. " All the endeavours
of my well-wishing teachers shattered themselves, however,
against the will of one of my guardians, who was also my
uncle. He wished that I should follow mercantile pursuits.
... I wrote him at that time that I should, indeed, be
obedient and learn the pursuit prescribed for me, but that I
should in any case continue my studies later."

On the 1st of March, 1850, Philipp Eeis entered the colour
establishment of Mr. J. F. Beyerbach, of Frankfort, as an
apprentice. By diligence and punctuality he soon won the

INVENTOR OF THE TELEPHONE.

esteem of his principal. All his leisure time he bestowed
upon his further education. He took private lessons in
mathematics and physics, and attended the lectures of
Professor E. Bottger, on Mechanics, at the Trade School.
And so the end of his apprenticeship arrived. At the
conclusion of it he entered the Institute of Dr. Poppe, in
Frankfort. " Several of my comrades in this establishment,
young people of sixteen to twenty years old, found it, as I
did, a defect that no natural history, history, or geography,
was taught. We determined, therefore, to instruct one
another in these subjects. I undertook geography, and
formed from this first occasion of acting as teacher the con-
viction that this was my vocation. Dr. Poppe confirmed me
in this view and aided me by word and deed."

In the year 1851, whilst resident in Frankfort, Eeis had
become a member of the Physical Society of that city. This
Society, which still flourishes, then held, and still continues
to hold, its meetings in the Senckenburg Museum. Lectures
in Chemistry and Physics are delivered by resident professors
in regular courses every week throughout the winter, under
the auspices of this Society ; and every Saturday evening is
devoted to the exposition of recent discoveries or inventions
in the world of physical science, astronomy, etc. The most
active members of this Society during the time of Eeis's
connection with it were the late Professor Bottger, Professor
Abbe (now of Jena), and Dr. Oppel, all of whom contributed
many valuable original memoirs to the JakresbericJite, or
Annual Eeports, published by the Society. Amongst its
corresponding and honorary members it counted the names
of all the best scientific men of Germany, and also the names
of Professor Faraday, Professor Sturgeon, and Sir Charles
Wheatstone. Doubtless the discussion of scientific questions
at this Society greatly influenced young Eeis. He remained
for three years a member, but dropped his connexion for a

B 2

PHILIPP REIS,

time on leaving Frankfort. He subsequently rejoined the
Society in the session of 1860-61, remaining a member until
1867, when he finally resigned.

In the winter of 1854-5 we find him most zealously busied
with preparations for carrying out his decision to become a
teacher. In 1855, he went through his year of military
service at Cassel. Eeturning to Frankfort, he worked away
with his customary and marvellous energy, attended lectures
on mathematics and the sciences, worked in the laboratory,
and studied books on Pedagogy. " Thus prepared, I set my
mind on going to Heidelberg in order to put the finishing
touch to my education as teacher. I wanted to settle down
in Frankfort in this capacity, and undertake instruction in
mathematics and science in the various schools. Then in
the spring of 1858, I visited my former master, Hofrath
Gamier, in whom I had ever found a fatherly friend. When
I disclosed to him my intentions and prospects, he offered me
a post in his Institute. Partly gratitude and attachment,
and partly the ardent desire to make myself right quickly
useful, induced me to accept the proffered post."

In the autumn of the year 1858 he returned to Friedrichs-
dorf, and in September 1859 he married and founded his
peaceful home.

Until Easter, 1859, he had but few lessons to give ; that
he utilised every moment of his spare time most conscien-
tiously in earnest activity and sound progress is nothing
more than was to be expected from what has been said
above.

It was during this time that Eeis undertook the first ex-
perimental researches of an original nature. Working almost
alone, and without any scientific guide, he was led into lines
of thought not previously trodden. He had conceived an
idea that electrical forces could be propagated across space
without any material conductor in the same way as light is

INVENTOR OF THE TELEPHONE.

propagated. He made many experiments on the subject,
the precise nature of which can never now be known, but in
which a large concave mirror was employed in conjunction
with an electroscope and a source of electrification. The
results which he obtained he embodied in a paper, of which
no trace now remains, bearing as its title ' On the Eadiation
of Electricity/ This paper he sent in 1859 to Professor
Poggendorff for insertion in PoggendorfFs well-known
' Annalen der Physik.' Greatly to his disappointment the
memoir was not accepted by Professor Poggendorff. Its
rejection was a great blow to the sensitive and highly strung
temperament of the young teacher ; and as will be seen was
not without its consequences.

The other piece of original work undertaken at this time
was the research which resulted in his great invention — the
Telephone. From the brief biographical notes written by
the lamented inventor in 1868 we extract the following : —

" Incited thereto by my lessons in Physics in the year
1860, I attacked a work begun much earlier concerning the
organs of hearing, and soon had the joy to see my pains
rewarded with success, since I succeeded in inventing an
apparatus, by which it is possible to make clear and evident
the functions of the organs of hearing, but with which also
one can reproduce tones of all kinds at any desired distance
by means of the galvanic current. I named the instrument
' Telephon.' The recognition of me on so many sides, which
has taken place in consequence of this invention, especially
at the Naturalists' Association (Versammlung Deutscher
Naturforscher) at Giessen, has continually helped to quicken
my ardour for study, that I may show myself worthy of the
luck that has befallen me."

His earliest telephones were made by his own hands, in a
little workshop behind his house, whence he laid on wires
into an upper room. He also carried a wire from the physical

PHILIPP REIS,

cabinet of Garnier's Institute across the playground into one
of the class-rooms for experimental telephonic communica-
tion ; and a firmly established tradition of the school is still
preserved, that the boys were afraid of making a noise in
that class-room for fear Herr Eeis should hear them in his
place amongst his favourite instruments.

In 1862 Eeis sent once again to Professor Poggendorff a
memoir, this time on the Telephone. This, in spite of the
advocacy of Professor Bottger and of Professor Miiller of
Freiburg, both of whom wrote, was declined by Professor
Poggendorff, who treated the transmission of speech by
electricity as a myth. Eeis, who was convinced that the
rejection was because he was " only a poor schoolmaster,"
was more deeply pained than ever.

Of the various public exhibitions of the Telephone given
by Eeis in the years 1861 to 1864, much will be found in
the latter part of this book in which the contemporary
notices are reprinted. The first public lecture was in 1861,
before the Physical Society of Frankfort (see p. 50), the
last the above-mentioned occasion at Giessen (see p. 93) in
1864. By this time Eeis's invention was becoming widely
known. In addition to his own lectures on the subject, the
Telephone had been the subject of lectures in various parts
of Germany. It was lectured upon by Professor Buff in
Geissen twice, by Professor Bottger both in Frankfort and
in Stettin ; by Professor . H. Pick, by Professor Osann of
Wurtzburg, by Professor Paul Eeis of Mainz, and by others.
In 1863 Eeis's Telephone was shown by Dr. Otto Volger,
Founder and President of the Free German Institute (Freies
Deutsches Hochstift), to the Emperor of Austria and to King
Max of Bavaria, then on a visit to Frankfort.

Telephones were being sent to various parts of the world.
They were to be found in the Physical Laboratories of Munich,
Erlangen, Wiesbaden, Vienna, and Cologne. They were

INVENTOR OF THE TELEPHONE.

sent to distant parts of the world, to London,* to Dublin, to
Tiflis in the Caucasus. In Manchester, before the Literary
and Philosophical Society, Eeis's Telephone was shown in
1865 by Professor Clifton, who, however, from not having
Eeis's own original memoirs on the subject before him,
utterly mistook — if the Journal of Proceedings be not in error
— the nature of the instrument, and not knowing the theory
of vibration of the tympanum so beautifully demonstrated
by Eeis, imagined the instrument to be a mere harmonic
telegraph for transmitting code signals in fixed musical
tones ! Telephones, too, were becoming an article of commerce
and, good and bad,t were being bought for the purpose of
placing them in collections of scientific apparatus. The
invention was, however, too soon for the world. To Eeis's
great disappointment, the Physical Society of Frankfort took
no further notice of the invention, the lustre of which shone
upon them. He resigned his membership in the Society in
October 1867. The Free German Institute of Frankfort, to
which Eeis had next betaken himself, though electing him
to the dignity of honorary membership, left the invention
aside as a philosophic toy. The Naturalists' Assembly,
including all the leading scientific men of Germany, had
indeed welcomed him at Giessen ; but too late. The sensitive
temperament had met with too many rebuffs, and the fatal
disease with which he was already stricken told upon his
energies. In particular the rejection of his earlier researches
had preyed upon his disposition. It is narrated by eye-
witnesses still living, how, after his successful lecture on the

* An autograph letter of Philipp Eeis to Mr. W. Ladd, the well-known
instrument maker of Beak Street, London, describing his telephone, is
still preserved, and is now in possession of the Society of Telegraph
Engineers and Electricians of London. It is reproduced at p. 81.

t As to the difference in quality of the instruments, see the testimony
of the maker, Albert of Frankfort, on p. 44. Prof. Pisko (see p. 101) seems
to have had a peculiarly imperfect instrument.

8 PHILIPP REIS,

Telephone at Giessen, Keis was asked by Professor Poggen-
dorff, who was present, to write an account of his instrument
for insertion in the ' Annalen/ to which request Eeis's reply
was : " Ich danke IJinen recht sehr, Herr Professor ; es ist zu
spat. Jetzt will i c h nicht ihn schicken. Mein Apparat wird
ohne Beschreibung in den Annalen lekannt werden"

Haemorrhage of the lungs and a loss of voice, which
eventually became almost total, intervened to incapacitate
him for work, and especially from working with the telephone.
In 1873 he disposed of all his instruments and tools to
Garnier's Institute. To Herr Garnier he made the remark
that he had showed the world the way to a great invention,
which must now be left to others to develop. At last the
end came. The annual Eeport of Garnier's Institute for the
academic year 1873-1874 contains the following brief notice
of the decease and labours of Philipp Eeis : —

" At first active in divers subjects of instruction, he soon
concentrated his whole faculties upon instruction in Natural
Science, the subject in which his entire thought and work lay.
Witnesses of this are not only all they who learned to know
him in Frankfort, in the period when he was preparing for
his vocation as teacher, but also his colleagues at the Institute,
his numerous pupils, and the members of the Naturalists'
Association (Naturforscher Versammlung) at Giessen, who,
recognising his keen insight, his perseverance and his rich
gifts, encouraged him to further investigations in his newly
propounded theories. To the Association at Giessen he
brought his Telephone. To the Association at Wiesbaden,
in September 1872, he intended to exhibit a new ingeniously
constructed gravity-machine, but his state of health made it
impossible. This had become such during several years, that
he was enabled to discharge the duties of his post only by
self-control of a special, and, as is generally admitted,
unusual nature; and the practice of his vocation became

INVENTOR OF THE TELEPHONE.

more difficult when his voice also failed. In the summer of
1873 he was obliged, during several weeks, to lay aside his •
teaching. As by this rest and that of the autumn vacation
an improvement in his condition occurred, he acquired new
hopes of recovery, and resumed his teaching in October with
his customary energy. But it was only the last flickering
up of the expiring lamp of life. Pulmonary consumption,
from which he had long suffered, laid him in December upon
the sickbed, from which after long and deep pains, at five
o'clock in the afternoon, on the 14th of January, 1874, he
was released by death."

The closing words of his autobiographical notes, or " curri-
culum vitce" as he himself styled them, were the fol-
lowing : —

" As I look back upon my life I can indeed say with the
Holy Scriptures that it has been ' labour and sorrow/ But I
have also to thank the Lord that He has given me His
blessing in my calling and in my family, and has bestowed
more good upon me than I have known how to ask of Him.
The Lord has helped hitherto ; He will help yet further."

In 1877, when the Magneto-Telephones of Graham Bell
began to make their way into Europe, the friends of Philipp
Eeis were not slow to reclaim for their deceased comrade the
honours due to him. In December 1877, as the columns
of the Neue Frankfurter Presse show, a lecture was given
upon the history of the Telephone, at the Free German
Institute, in Frankfort, by Dr. Volger, its President, the same
who in 1863 had shown the Telephone to the Emperor of
Austria. On that occasion the Telephone of Eeis's own
construction, presented by him to the Institute after his
exhibition of it in 1862, was shown.

Early in 1878 a subscription was raised by members of the
Physical Society of Frankfort for the purpose of erecting a
monument to the memory of their former colleague. This

PHILIPP EEIS,

monument, bearing a portrait medallion, executed by the
sculptor, Carl Kumpf, was duly inaugurated on Sunday,
December 8, 1878, when an appropriate address was pro-
nounced by the late Dr. Fleck, of Frankfort. The ' Jahres-
bericht,' of the Physical Society for 1877-78 (p. 44), contains
the following brief record : —

" The Society has erected to the memory of its former
member, the inventor of the Telephone, Philipp Eeis
(deceased in 1874), teacher, of Friedrichsdorf (see 'Jahres-
bericht/ 1860-61, pp. 57-64; and 1861-62, p. 13), in the
cemetery of that place, a monument which was inaugurated
on the 8th of December, 1878. This monument, an obelisk
of red sandstone, bears in addition to the dedication, a well-
executed medallion portrait of Philipp Eeis, modelled by the
sculptor, A. C. Eumpf, and executed galvanoplastically by
G. v. Kress."

The inscription on Eeis's monument in the Friedrichsdorf
Cemetery is : —

HIER EUHT

PHILIPP KEIS

GEB. 7. JANUAE 1834
GEST. 14. JANUAR 1874

SEINEM VERDIENSTVOLLEN

MITGLIEDE
DEM EEFINDER DBS

TELEPHOKS
DER PHYSIKALISCHE VEREIN

ZU
FBANKFURT-A-M.

ERRICHTET
1878

INVENTOR OF THE TELEPHONE.

PRINCIPAL DATES IN EEIS'S LIFE.

1834 January 7 .

1850 March 1 . .

1855

1858

1859 September 14.

1860

1861 October 26

November 16.

1861 December

1862 May 8 .
„ May 11 .

Philipp Eeis born.

Apprenticed to Beyerbach.

Year of Military Service at Cassel.

Settled in Friedrichsdorf.

Married.

Invented the Telephone.

Eead Paper "On Telephony by the
Galvanic Current " before the Phy-
sical Society of Frankfort-on-the-
Main.

Eead Paper to the Physical Society
of Frankfort-on-the-Main, entitled
"Explanation of a new Theory
concerning the Perception of Chords
and of Timbre as a Continuation
and Supplement of the Eeport on
the Telephone."

Wrote out his Paper "On Tele-
phony/' as printed in the ' Jahres-
bericht.'

Notice in ' Didaskalia ' of Eeis's
invention.

Lectured and showed the Telephone
to the Free German Institute
(Freies Deutsches Hochstift) in
Frankfort-on-the-Main.

Article on the Telephone, communi-
cated by Inspector Von Legat to the
Austro-German Telegraph Society,
and subsequently printed in its
' Zeitschrift ' (Journal).

PEILIPP EEIS,

1863 July 4 . .
„ September 6 .
„ Sept. 17-24 .

1864 February 13 .

„ September 21

1872 September

1874 January 14

Showed his improved Telephone to
the Physical Society of Frank -
fort-on-the-Main.

Eeis's Telephone shown to the Em-
peror of Austria and the King of
Bavaria, then visiting Frankfort.

Meeting of the "Deutscher Natur-
forscher " at Stettin ; Eeis's Tele-
phone shown there by Professor
Bottger.

Meeting of the " Oberhessische Ge-
sellschaft fur Natur- und Heil-
kunde " at Giessen ; Lecture by
Professor Buff, and exhibition by
Eeis of his Telephone.

Meeting of the "Deutscher Natur-
forscher" at Giessen. Eeis gave
an explanation of the Telephone
and the history of its invention,
and exhibited it in action before
the most distinguished scientific
men of Germany.

Meeting of the "Deutscher Natur-
forscher " at Wiesbaden ; Eeis
announced to show his "Fall-
maschine," but prevented by ill-
health.

Philipp Eeis died.

IN YEN TOE OF THE TELEPHONE.

Fig. 1.
Monument to Pliilipp Reis in the Cemetery at Friedrichsdorf.

14 PHILIPP BEIS,

CHAPTEE II.

THE INVENTOR'S APPARATUS.

IN describing the various forms successively given by the
inventor to his apparatus, as he progressed, from the earliest
to the latest, it will be convenient to divide them into two
groups, viz. the Transmitters and the Eeceivers.

A. — Eeis's Transmitters.

So far as can be learned, Eeis constructed transmitters in
some ten or twelve different forms. The complete series in
this course of evolution does not now exist, but the principal
forms still remain and will be described in their historical
order. Theoretically, the last was no more perfect than the
first, and they all embody the same fundamental idea : they
only differ in the mechanical means of carrying out to a
greater or less degree of perfection the one common principle
of imitating the mechanism of the human ear, and applying
that mechanism to affect or control a current of electricity by
varying the degree of contact at a loose joint in the circuit.

First Form. — THE MODEL EAR.

Naturally enough the inventor of the Telephone began
with crude and primitive * apparatus. The earliest form of

* Dr. Messel, F.C.S., a former pupil of Reis, and an eye-witness of his
early experiments, makes, in a letter to Professor W. F. Barrett, the

INVENTOR OF THE TELEPHONE. 15

telephone-transmitter now extant, was a rough model of the
human ear carved in oak wood, and of the natural size, as
shown in Figs. 2, 3, 4, & 5.

The end of the aperture a was closed by a thin membrane
&, in imitation of the human tympanum. Against the centre
of the tympanum rested the lower end of a little curved
lever c d, of platinum wire, which represented the " hammer "
bone of the human ear. This curved lever was attached to
the membrane by a minute drop of sealing-wax, so that it
followed every motion of the same. It was pivoted near its
centre by being soldered to a short cross-wire which served
as an axis ; this axis passing on either side through a hole
in a bent strip of tin-plate screwed to the back of the wooden
ear. The upper end of the curved lever rested in loose
contact against the upper end g of a vertical spring, about one
inch long, also of tin-plate, bearing at its summit a slender
and resilient strip of platinum foil. An adjusting-screw, h,
served to regulate the degree of contact between the vertical
spring and the curved lever. The conducting- wires by which
the current of electricity entered and left the apparatus were
connected to the screws by which the two strips of tin-plate

following very interesting statement : " The original telephone was of a
most primitive nature. The transmitting instrument was a bung of a
beer-barrel hollowed out, and a cone formed in this way was closed with
the skin of a German sausage, which did service as a membrane. To this
was fixed with a drop of sealing-wax a little strip of platinum correspond-
ing to the hammer of the ear, and which closed or opened the electric
circuit, precisely as in the instruments of a later date. The receiving
instrument was a knitting needle surrounded with a coil of wire and placed
on a violin to serve as a sounding board. It astonished every one quite
as much as the more perfect instruments of Bell now do. The instrument
I have described has now passed into the hands of the Telegraph Depart-
ment of the German Government." [The instrument now in the museum
of the Keichs Post-Amt in Berlin is not this, but is the first of the " Im-
proved " Telephones described later by Reis in his " Prospectus " (see
p. 85), and is stamped " Philipp Reis," " 1863," " No. 1."] S.P.T.

PHILIPP REIS,

were fixed to the ear. In order to make sure that the current
from the upper support of tin should reach the curved lever,

Fig. 2.

Fig. 4

Fig. 5.

INVENTOR OF THE TELEPHONE.

another strip of platinum foil was soldered on the side of the
former, and rested lightly against the end of the wire-axis, as
shown in magnified detail in Fig. 6. If now any words or

Fig. 6.

sounds of any kind were uttered in front of the ear the
membrane was thereby set into vibrations, as in the human
ear. The little curved lever took up these motions precisely
as the " hammer "-bone of the human ear does ; and, like the
" hammer "-bone, transferred them to that with which it was
in contact. The result was that the contact of the upper end
of the lever was caused to vary. With every rarefaction of
the air the membrane moved forward and the upper end of
the little lever moved backward and pressed more firmly
than before against the spring, making better contact and
allowing a stronger current to flow. At every condensation
of the air the membrane moved backwards and the upper end
of the lever moved forward so as to press less strongly than
before against the spring, thereby making a less complete
contact than before, and by thus partially interrupting the
passage of the current, caused the current to flow less freely.

18 PHILJPP EEIS,

The sound waves which entered the ear would in this fashion
throw the electric current, which flowed through the point of
variable contact, into undulations in strength. It will be
seen that this principle of causing the voice to control the
strength of the electric current by causing it to operate upon
a loose or imperfect contact, runs throughout the whole of
Eeis's telephonic transmitters. In later times such pieces of
mechanism for varying the strength of an electric current
have been termed current-regulators.* It would not be
inappropriate to describe the mechanism which Eeis thus
invented as a combination of a tympanum with an electric
current-regulator, the essential principle of the electric
current-regulator being the employment of a loose or im-
perfect contact between two parts of the conducting system,
so arranged that the vibrations of the tympanum would alter
the degree of contact and thereby interrupt in a correspond-
ing degree the passage of the current.

Mr. Horkheimer, a former pupil of Eeis, informs me that
a much larger model of the ear was also constructed by
Eeis. No trace of this is, however, known.

Second Form. — TIN TUBE.

The second form, a tube constructed by Eeis himself, of
tin, is still to be seen in the Physical cabinet of Garnier's
Institute, at Friedrichsdorf, and is shown in Fig. 7. It
consists of an auditory tube a, with an embouchure represent-
ing the pinna or flap of the ear. This second apparatus
shows also a great similarity with the arrangement of the
ear, having the pinna or ear-flap, the auditory passage, and
the drum-skin (a, b, c). Upon the bladder c there still
remains some sealing-wax, by means of which a little strip

* Or sometimes " tension-regulators," though the latter term is acknow-
ledged by most competent electricians to be indcscriptive and open to
objection.

INVENTOR OF THE' TELEPHONE. 10!

of platinum, for the all-essential loose-contact that controlled
the current, had formerly been cemented to the apparatus.

Fig. 7.

Third Form. — THE COLLAR-BOX.

The third form, also preserved in the collection in Garnier's
Institute, is given in Fig. 8, which, with the preceding, is
taken by permission from the pamphlet of the late Professor
Schenk, consists of a round tin box, the upper part of which
fits upon the lower precisely like the lid of a collar-box.
Over this lid 6, which is 15 centimetres in diameter, was

Fig. 8.

formerly stretched the vibrating membrane, there being also
an inner flange of metal. Into a circular aperture below
opened an auditory tube- a, with an embouchure representing
the pinna. The precise arrangements of the contact-parts of
this apparatus are not known. Mr, Horkheimer, who aided
Eeis in his earlier experiments, has no knowledge o£ this
form,* which he thinks was ; made later than June* 1862.

c 2

PHILIPP REIS,

This is not improbable, as the design with horizontal mem-
brane more nearly approaches that of the tenth form, the
" Square-box " pattern.

Fourth Form, — THE BOEED-BLOCK.

The instrument described by " Keis in his paper " On
Telephony," in the Annual Eeport of the Physical Society of
Frankfort-on-the-Main, for 1860-61 (see p. 50), comes next
in order. The inventor's own description of this telephone
(Fig. 9) is as follows : —

" In a cube of wood, r s t u v w x, there is a conical hole a,
closed at one side by the membrane & (made of the lesser
intestine of the pig), upon the middle of which a little strip
of platinum is cemented as a conductor [or electrode]. This
is united with the binding screw p. From the binding
screw n there passes likewise a thin strip of metal over the
middle of the membrane, and terminates here in a little
platinum wire, which stands at right-angles to the length
and breadth of the strip. From the binding-screw p a

INVENTOR OF THE TELEPHONE.

conducting wire leads through the battery to a distant
station." The identical apparatus used by Eeis was after-
wards given by him to Professor Bottger, who later gave it
to Hofrath Dr. Th. Stein, of Frankfort, from whose hands it
has recently passed into the possession of the author of this
work. It possesses one feature not shown in the original
cut, viz. an adjusting screw, li, which, so far as the writer can
learn, was put there by Eeis himself. There appears no
reason to doubt this, since there was an adjusting screw in
Eeis's very earliest form of transmitter, the wooden ear. A
section of the actual instrument is given in Fig. 10.

Fig. 10.

Fifth Form. — THE HOLLOW CUBE.

Another form, a mere variety of the preceding, is described
as follows by Professor Bottger in his " Polytechnisches
Notizblatt " (see p. 61) :—

" A little light box, a sort of hollow cube of wood, has a
large opening at its front side and a small one at the back of
the opposite side. The latter is closed with a very fine
membrane (of pig's smaller intestine) which is strained stiff.
A narrow springy strip of platinum foil, fixed at its outer
part to the wood, touches the membrane at its middle ; a
second platinum strip is fastened by one of its ends to the

23 PHILIPP REIS,

wood at another spot, and bears at its other end a fine
horizontal spike, which touches the other little platinum
strip where it lies upon the membrane,"

Sixth Form. — THE WOODEN CONE.

Another transmitter, also a mere variety of the Fourth
Form, has been described to me by Herr Peter, of Friedrichs-
dorf, who assisted Reis in his earlier experiments. Fig. 11

Fig. 11.

is prepared from a rough sketch furnished me by the kindness
of Karl Reis. Herr Peter describes the apparatus as having
been turned out of a block of wood by Reis upon his own
lathe. The conical hole was identical with that of Fig. 9,
but the surrounding portions of the wood were cut away,
leaving a conical mouth-piece.

Seventh Form. — " HOCHSTIFT " FORM.

The engraving presented below (Fig. 12). has been engraved
with the utmost fidelity by Mr, J. D. Cooper, from a photo-
graph lent to the author by Ernest Horkheimer, Esq., of
Manchester, a former pupil of Reis. The original photograph
was taken in 1862, having been sent by Reis in June of that
year to Mr. Horkheimer, who had left for England. The
photograph was taken by Reis himself with his own camera,
the exposure being managed by a slight movement of the

INVENTOR OF THE TELEPHONE.

foot, actuating a pneumatic contrivance of Keis's own inven-
tion, which was originally designed to turn over the pages
of a music book at the piano. Reis is here represented as
holding in his hand the telephone with which he had a few
days preceding (May 11, 1862) achieved such success at his

lecture before the Freies Deutsches Hochstift (Free German
Institute) in Frankfort (see p. 66). This instrument was
constructed by Eeis, young Horkheimer assisting him in the
construction. Mr. Horkheimer has very obligingly indicated

PEILIPP REIS,

from memory the form of the instrument — but dimly seen in
the photograph — in a sketch from which Fig. 13 has been
prepared. Mr. Horkheimer adds that the cone was a wooden
one ; and that the square patch behind at the back was, he
thinks, a box to contain an electro-magnet.

Fig. 13.

Eighth Form. — LEVER FORM.

The Transmitter described with so much minuteness by
Inspector von Legat in his Eeport on Eeis's Telephone in
1862 (see p. 70), differs from the earliest and latest forms,
so much so that some have doubted whether this form was
really invented by Keis. It is not described anywhere else
than in Legat's Keport (in the " Zeitschrift " of the Austro-
German Telegraph Union, reprinted also in Dingler's
Journal), except in Kuhn's Handbook, where, however, the
description is taken from Legat. Nevertheless a comparison
of this instrument (Fig. 14) with the original model of the
ear, from which Eeis started, will show that it embodies no
new point. There is, first, a conical tube to receive the
sound, closed at its end with a tympanum of membrane.
There is next a curved lever, c d, the lower end of which rests
against the centre of the membrane. Thirdly, there is a ver-
tical spring, g, which makes contact lightly against the upper

INVENTOR OF THE TELEPHONE.

end of the curved lever. Lastly, there is an adjusting screw.
It may be further pointed out that in each case the current
enters (or leaves, as the case may be) the lever at its middle
point. This form of transmitter is so closely allied indeed
to the primitive " ear " as to be alike in every feature save
the external form of the sound-gathering funnel. The only
reasonable doubt is not whether it be, as Legat asserts, Keis's

Fig. 14.

transmitter, but whether it ought not in chronological order
to rank second. Legat's paper was not published, however,
till 1862, whilst the fourth form was described by Eeis in
1861. No trace of any instrument corresponding in form to
Fig. 14, save modern reproductions from Legat's drawing, has
been found. The instrument held by Keis in his harjd in
the photograph (Fig. 12) is so strikingly like the form
described by Legat, that it furnishes an additional reason for

PH1LIPP REIS,

accepting Legat's statement that this transmitter really is
Reis's invention.

Fig. 15.

Fiff. 1C

INVENTOE OF THE TELEPHONE.

Ninth Form. — TRANSITIONAL FORM.

Our knowledge of this form is derived solely from infor-
mation and sketches supplied by Mr. E. Horkheimer, who
assisted Eeis in its construction. Figs. 15 and 16 are
engraved after Mr. Horkheimer's sketches. The conical
mouthpiece was of wood : the contact pieces of platinum.
The point c was attached to a springy slip of brass, g, fixed
across the wooden box ; and the adjusting-screw, li, served to
regulate the degree of initial pressure at the point of contact
which controlled the current.

Tenth Form. — THE SQUARE Box.

The last form of Reis's Transmitter is that which has
become best known, being the only one (except Fig. 9) which
found its way into the market. It is here named, for the sake
of distinction, as the " Square Box " pattern. It consisted of

Fig. 17. Fig. 18.

a square wooden box, having a hinged lid. Fig. 17 is repro-
duced from Eeis's " Prospectus " (see page 85), whilst
Fig. 18 is taken from Prof. Schenk's biographical pamphlet.

28 PHILIPP EEIS,

In this instrument the idea of the human ear is still carried
out. The tin funnel, with its flaring embouchure, still repre-
sents the auditory tube and pinna. The tympanum, no
longer at the very end of the tube, is strained across a circular
aperture in the lid. Upon it rests the strip of platinum foil
which serves as an electrode, and resting in loose contact
with this lies the little angular piece of metal which Eeis
called the " Hammerchen." Above all lay a circular glass
disk (a cover to keep out the dust), which was removed
when the instrument was used. So sensitive did this form
prove itself that it was found unnecessary to speak right into
the mouthpiece, and the speaker in practice talked or sang
with his mouth at some little distance vertically above the
instrument ; a method which had the advantage of not so
soon relaxing the membrane by the moisture of the breath.
The figures show also the auxiliary apparatus attached at
the side, consisting of a key for interrupting the circuit
(added at first to enable the experimenters to single out the
" galvanic tones" from the reproduced tones, and later
applied, as Eeis explains in his " Prospectus," on page 87),
and an electro-magnet to serve as a " call," by which the lis-
tener at the other end could signal back to the transmitter.

This form of instrument, which has been so frequently
described in the Text-books of Physics, was constructed for
sale first by Albert of Frankfort, later by Ladd of London,
Konig of Paris, and Hauck of Vienna. Further details con-
cerning it will be found in this book, in Eeis's " Prospectus,"
and in other contemporary documents.

Although this form is the one most commonly referred to
as " the Eeis Telephone," it is evident from a consideration
of the entire group of forms that Eeis's invention was in no
way limited to one individual pattern of instrument. For in
all these forms there was embodied one all-embracing prin-
ciple ;— that of controlling the electric current by the voice

INVENTOR OF TEE TELEPHONE. 29

working upon a point of imperfect contact, by the agency of a
tympanum, thereby opening or closing the circuit to a greater
or less degree, and so regulating the flow of the current.

B. — Reis's Receivers.

First Form. — THE VIOLIN EECEIVER.

The first form of apparatus used by Eeis for receiving the
currents from the transmitter, and for reproducing audibly
that which had been spoken or sung, consisted of a steel
knitting-needle, round which was wound a spiral coil of silk-
covered copper-wire. This wire, as Eeis explains in his
lecture " On Telephony," was magnetised in varying degrees
by the successive currents, and when thus rapidly magnetised
and demagnetised, emitted tones depending upon the fre-
quency, strength, etc., of the currents which flowed round it.
It was soon found that the sounds it emitted required to be
strengthened by the addition of a sounding-box, or resonant-
case. This was in the first instance attained by placing the
needle upon the sounding-board of a violin. At the first
trial it was stuck loosely into one of the /-shaped holes of the

Fig 19.

violin (see Fig. 19) : subsequently the needle was fixed by its
lower end to the bridge of the violin. These details were
furnished by Herr Peter, of Friedrichsdorf, music-teacher in

PHIL1PP EEIS,

Garnier's Institute, to whom the violin belonged, and who
gave Eeis, expressly for this purpose, a violin of less value
than that used by himself in his profession. Eeis, who was
not himself a musician, and indeed had so little of a musical
ear as haidly to know one piece of music from another, kept
this violin for the purpose of a sounding-box.. It has now
passed into the possession of Garnier's Institute. It was in
this form that the instrument was shown by Eeis in October
1861 to the Physical Society of Frankfort.

Second Form. — THE CIGAR-BOX EECEIVER.

Later a shallow rectangular wooden box was substituted
for the violin, and the spiral was laid horizontally upon it
(Fig. 20). The date when this modification was made was

Fig. 20.

either at the end of 1861 or the early spring of 1862. A
cigar-box was the actual sounding-box, and the needle was
supported within the coil, but not touching it, with its ends
resting upon two wooden bridges.

Third Form.— THE ELECTRO-MAGNET EECEIVER.
Though the precise history of this form of telephonic
receiver is defective, there can be little doubt that it was
conceived by Eeis amongst his earliest researches. When
there were in common use so many electric and telegraphic
instruments in which an electro-magnet is employed to move
an armature to and fro, it is not surprising that Eeis should

INVENTOR OF THE TELEPHONE. 31

have thought of availing himself of this method for repro-
ducing the vibrations of speech. Speaking of the two parts
of his invention, the Transmitter and the Eeceiver, Eeis
himself says :* " The apparatus named the ' Telephone/ con-
structed by me, affords the possibility of evoking sound-
vibrations in every manner that may be desired. Electro-mag-
netism affords the possibility of calling into life at any given
distance vibrations similar to the vibrations that have been
produced, and in this way to give out again in one place the
tones that have been produced in another place." A remark,
almost identical with this, is also made by Inspector von
Legat (see p. 74) in his Eeport on Eeis's Telephone. It
may be here remarked that the form of this receiver is
known only from the figure and description given in that
Keport, and from the extract therefrom printed in Kuhn's
' Handbook ' (see p. 109). Keis seems to have very soon
abandoned this form, and to have returned to the needle,
surrounded by a coil, in preference to the electro-magnet. The
electro-magnet form is, however, of great importance, because
its principle is a complete and perfect anticipation of that of
the later receivers of Yeates, of Gray, and of Bell, who each,
like Keis, employed as receiver an electro-magnet the function
of which was to draw an elastically mounted armature back-
wards and forwards, and so to throw it into vibrations corre-
sponding to those imparted to the transmitting apparatus.
Fig. 21 shows the disposition of the electro-magnet, and of
its vibratory armature upon a sounding-board. This appa-
ratus was a good deal larger than most of Keis's instruments.
The sounding-board was nearly a foot long : the coils of the
electro-magnet were six inches long, and over an inch thick.
The armature, a rod of iron of elliptical section, was affixed
cross-wise at the end of a "light and broad J) vertical lever,

* See Die OeschicJite und Entwickelung des Elektrisclien Fernsprech-
wesens (issued, officially from the. Imperial German Post-office, 1880), p. 7L

PHILIPP REIS,

about seven inches long, which seems to have been made of
wood, as in Legat's Report it is also denominated as a
"plank" (Balken).

Fourth Form. — THE KNITTING-NEEDLE KECEIVER.

The final form adopted by Eeis for his Keproducing-
apparatus is that commonly known as the Knitting-needle
Eeceiver. It differs only from the first form in that the
needle and its surrounding spiral no longer stand upright on

INVENTOR OF THE TELEPHONE.

a violin, but lie horizontally upon a rectangular sounding-
box of thin pine wood. The coil of silk-covered copper wire
is wound upon a light wooden bobbin, instead of being
twisted round the needle itself. Two wooden bridges stand

Fig. 22.

Fig. 23.

upon the sounding-box, and through these pass the pro-
truding ends of the needle, whilst an upper box or lid,
hinged to the lower at the back, is added above. Figs. 22
and 23 show this form, the former being reproduced from
Keis's own Prospectus (see p. 85), the latter being from
Miiller-Pouillet's ' Text-book of Physics ' (see p. 95). Herr

34 PHILIPP REIS,

Albert, mechanician, of Frankfort, who made and sold the
Reis telephones, says that the upper box was added at his
suggestion. Originally it was so constructed (see Tig. 22),
that when closed it pressed upon the steel needle. In the
instruments of later date, the notches which fitted over the
needle were cut so deeply (see Fig. 23), that the lid did not
press upon the wire. Eeis's own instructions are (see p. 86)
that the sound is intensified by firmly pressing the lid
against the needle, as was done occasionally by the listeners
who pressed their ears against the lid in order to hear more
distinctly. The little key seen at the end of the sounding-
box, in Fig. 22, was used for interrupting the current and so
to telegraph back signals to the transmitter.

INVENTOR OF THE TELEPHONE. 35

CHAPTER III.

THE CLAIM OF THE INVENTOR.

IN the present century, when so many facilities exist for the
diffusion of knowledge, and when every new discovery and
invention is eagerly welcomed and immediately noised
abroad to every country of the globe, it is hard to believe
that the inventor of an instrument of the highest scientific
value, destined to play an important part in social and com-
mercial life, should have been suffered to live and die in
unrecognised obscurity. Still harder is it to believe that his
invention passed into almost complete oblivion, unacknow-
ledged by most of the leading scientific men of his day and
generation. But hardest of all is it to believe that when
at last attempts were made to give to him, whose name and
fame had thus been permitted to languish, the credit of the
splendid researches in which he wore his life away, those
attempts could be met on the one hand by an almost complete
apathy, and on the other by a chorus of denial, not only
that any such invention was made, but that the inventor had
ever intended to invent anything of the kind. Yet nothing
less than this has happened. Philipp Reis, the inventor of
the Telephone, the first to scheme, and carry out into
execution, an instrument for conveying to a distance by
means of electric currents the tones of human speech and
human song, is no longer amongst the living. He cannot

D 2

36 PHIL1PP REI8,

reclaim for himself the honours that have been showered
upon the heads of others, who, however worthy of those
honours they were — none will deny that — were only not the
first to deserve them. In his quiet grave, in the obscurity of
the German village where his daily work was done, he sleeps
undisturbed by the strife of tongues. To him it matters
nothing now, whether his genius be recognised and his
invention applauded, or whether ignorance, and calumny, and
envy, alike decry both. Nevertheless, the memory of him
and of his work will live, and will descend to posterity as of
one whom his own generation knew not, whose peculiar
greatness passed unheeded save by a chosen few. Nor will
posterity be the less ready to accord honour to him who in his
own day could not even obtain justice. Yet something more
than a mere historic justice for the poor schoolmaster of Fried-
richsdorf does the world owe ; justice to the great invention
that is now imperishably associated with his name : justice
to the struggling family whom, instead of enriching, it
impoverished ; and, not least, the justice of patience, whilst
the story of his life and work, and the words he himself has
written thereupon, are unfolded.

The point at issue, and for which justice has been invoked,
and of which ample proof is given in these pages, is not
whether Philipp Keis invented a telephone — that is not denied
— but whether Philipp Eeis invented the Telephone. The
irony of fate, not .to say the curious ignorance which is often
called by a less polite name, has decreed by the mouth of
popular scientific writers, of eminent engineers, and of accom-
plished barristers, that Reis's invention was not an instrument
for transmitting human speech at all — was not intended
even for this — that it was a purely musical instrument in its
inception, and that it has always so remained. These clever
persons begin to persuade themselves of this view, and forth-
with invent a question-begging epithet, and dub the instru-

INVENTOR OF THE TELEPHONE. 37

ment as a mere " tone-telephone " / If some unprejudiced
person ventures to speak of Eeis's instrument as having, as
a matter of history, transmitted speech, all the contemptuous
reply that he gets from the eminent somebody, who poses as
an authority for the moment, is : Oh, but, you know, it was
only a tone-telephone, a musical toy, and when some one was
singing to it you fancied you caught the words of the song
which, during singing, were occasionally projected along with
the music. I've always regarded the accounts of its transmission
of speech as a good joke ; all it could possibly do was occasionally
to utter an articulate noise in combination with a musical tone.
Besides, you know, Mr. Reis was a musical man, who only
intended it to sing, and if it spoke it only spoke by accident ; but
such an accident never did or could occur, because the construc-
tion of it shows that it not only did not but could not transmit
speech. If Mr. Eeis had really penetrated the fundamental
principle of the articulating telephone, he would have arranged
his instruments very differently ; and then, you know, if he
really had transmitted speech the discovery would have attracted
so much attention at the time. Moreover, if he had meant it to
talk, he would have called it the articulating telephone, and not
a telephone for transmitting tones, you know ; no one before
Graham Bell ever dreamed of using a tympanum to catch
articulate sounds, or had he done so he would have been
laughed at.

To all such clap - trap as this — and there has been
enough ad nauseam of such — the one reply is silence, and a
mute appeal to the original writings of Eeis and his con-
temporaries, and to the tangible witness of inexorable
scientific facts. All the most important of these will be
found in their appropriate places. They amply establish the
following points : —

I. — Eeis's Telephone was expressly intended to transmit
speech.

38 PHILIPP REIS,

II. — Eeis's Telephone, in the hands of Eds and his con-
temporaries, did transmit speech.

III. — Eeis's Telephone will transmit speech.

Before proceeding to discuss these three points we will
pause for a moment, first to clear away a lurking verbal
fallacy, then to point out the partial historic acknowledg-
ment already conceded to Eeis's claims.

Eeis did not call his instrument an " articulating telephone."
Neither did he call it a <(tone telephone." He called it
simply " The Telephone " (Das Telephon),* as will be seen in
his own first memoir (p. 57). He did speak of his instru-
ment again and again as an instrument "for reproducing
tones." But it must be remembered that the German word
Ton (plural Tone) used by Eeis is more nearly equivalent to
our English word " sound," and includes articulate as well as
musical tones, unless the context expressly indicates other-
wise. So that when Eeis talked of the Reproduction of
Tones he was using words which did not limit his meaning
to musical tones, as indeed his memoirs show in other ways.
He started from a consideration of the mechanical structure
of the human ear, and endeavoured to construct an instrument
on those lines because the ear can take up all kinds of tones.
Eeis was not so foolish as to imagine that the construction of
the human ear was solely designed for musical, to the exclusion
of articulate tones. We are not aware that the epithet, Tone-

* The name " Telephone " had already been applied by Sir C. Wheat-
stone (183 L) to an acoustic arrangement for transmitting sounds through
wooden rods to a distant place in a purely mechanical manner. It is
needless to observe that speech as well as music can be thus transmitted ;
and though Wheatstone gave telephonic concerts, this does not prove (nor
do telephonic concerts given through Eeis's instrument prove) that speech
could not be transmitted also. The name " Fernsprecher," now used in
Germany for the Telephone, was only suggested in 1877 by Dr. Stephan,
Postmaster of the German Empire, in obedience to the absurd fashion
which has raged since 1871 in Germany of rejecting words of classic
derivation.

INVENTOR OF THE TELEPHONE. 39

Telephone, was ever applied to Eeis's instruments until it
became advisable (!) to seek a means of disparaging an old
invention in order to exalt a new one. And it is a curious
point that the true musical " tone-telephones," i.e. instruments
designed expressly to transmit specific musical tones for the
purpose of multiple telegraphy, were invented (by Varley,
Gray, La Cour, Graham Bell, and Edison) long after Eeis's
Telephone, between the years 1870 and 1876. All these
were dependent practically upon the tuning-fork system of
vibration, whereas Eeis's system was based on the tympanum
of the ear. To classify Eeis's invention with these would be
absurd.

Having shown the fallacy bound up in the term " tone-
telephone," we will dismiss the point with the remark that
henceforth it will be a waste of time to argue with any person
who applies that question- begging epithet to Eeis's in-
vention.

Partial historic acknowledgments of Eeis's claims as
inventor of The Telephone have been made from time to time
by those best qualified to speak.

Mr. Edison, the inventor of the famous lamp-black button
transmitter, which he christened later as " The Carbon Tele-
phone," has himself stated in his account of his inventions,*
that he was started upon this line of investigation by having
put into his hand, by the late Hon. Mr. W. Orton, a manu-
script translation of Legat's Eeport on Eeis's Telephone,
given in the Journal of the Austro-German Telegraph Union
(see Translation, p. 70). So that he was, therefore, aware
at least of this : that in Eeis's instruments " single words
uttered, as in reading, speaking, and the like, were perceptible
indistinctly, nevertheless, here also the inflexions of the
voice, the modulations of interrogation, exclamation, wonder,

* See proceedings in U. S. Court (Dowd suit), Edison's second answer,
and Prescott's ' The Speaking Telephone,' p. 218.

40 PHILIPP EEIS,

command, etc., attained distinct expression." So far as Mr.
Edison is concerned, therefore, Eeis is his starting-point by
his own direct avowal.

Professor Graham Bell has not failed to acknowledge his
indebtedness to Eeis, whose entry " into the field of telephonic
research " he explicitly draws attention to by name, in his
" Eesearches in Electric Telephony," read before the American
Academy of Sciences and Arts, in May 1876, and repeated
almost verbatim before the Society of Telegraph Engineers,
in November 1877. In the latter, as printed at the time,
Professor Bell gave references to the researches of Eeis, to
the original paper in Dingler's 'Polytechnic Journal' (see
Translation, p. 61) ; to the particular pages of Kuhn's
volume in Karsten's 'Encyclopaedia' (see p. 106), in which
diagrams and descriptions of two forms of Eeis's Telephone
are given ; and where mention is also made of the success
with which exclamatory and other articulate intonations of
the voice were transmitted by one of these instruments ; and
to Legat's Eeport, mentioned above (and given in full on
p. 70). Professor Bell has, moreover, in judicial examina-
tion before one of the United States Courts expressly and
candidly stated,* that whilst the receivers of his own early tone-
telephones were constructed so as to respond to one musical
note only, the receiver of Eeis's instrument, shown in Legat's
Esport (as copied in Prescott's ' Speaking Telephone,' p. 10),
and given on p. 109 of this work, was adapted to receive
tones of any pitch, and not of one tone only. It is further
important to note that in Professor Bell's British Patent he
does not lay claim to be the inventor, but only the improver
of an invention : the exact title of his patent is, " Improve-
ments in Electric Telephony (Transmitting or causing sounds
for Telegraphing Messages) and Telephonic Apparatus."

* Published volume of Proceedings in the United States Patent Office,
before the Commissioner of Patents. Evidence for A. G. Bell, p. 6.

INVENTOR OF THE TELEPHONE. 41

So far as Professor Bell is concerned, therefore, he is guilt-
less of stigmatising the Eeis instrument as a mere " tone-
telephone."

Professor Dolbear, the inventor of the " Static Eeceiver "
form of Telephone, is still more explicit in avowing Keis's
claim. In the report of his paper on "the Telephone,"
read, March 1882, before the Society of Telegraph Engineers
and of Electricians* we find : " The speaker could testify
that the instrument would talk, and would talk well. The
identical instruments employed by Eeis would do that, so
that Eeis's transmitters would transmit. Secondly, his
receiver would receive; and Eeis did transmit and receive
articulate speech with such instruments."

As far as Professor Dolbear is concerned, therefore, he
admits in unequivocal terms the whole claim of Eeis to be
the inventor of The Telephone.

Count du Moncel, author of a work on the Telephone, which
has run through several editions, though he has classified
Eeis's instrument as a mere " tone- telephone," has recently
admitted! that he was, until the year 1882, ignorant of
some of Eeis's instruments and of his original papers. He
has, moreover, added these words : " Nevertheless, it would
not be just not to acknowledge that the Eeis Telephone formed
the starting-point of all the others ; " also these significant
lines : " It is probable that in this matter, as in the greater
number of modern inventions, the original inventor obtained
only insignificant results, and that it was the man who first
succeeded in arranging his apparatus so as to obtain really
striking results that received the honour of the discovery and
rendered it popular."

So far as the Count du Moncel is concerned, therefore,
the claims of Philipp Eeis to be the inventor of the tele-

* Proc. Soc. Telegr. Engin. and Electr. vol. xi. p. 134, 1882.
t ' Electrical Review,' July 22, 1882, p. 49.

42 PHILIPP REIS,

phone are admitted, though hesitatingly, to be historically
just.

We now return to the proof of the three points previously
enunciated.

I. — Reis's Telephone was expressly intended to
transmit speech.

Keis's first instrument was (see p. 16) nothing else than a
model of the mechanism of the human ear. Why did he
choose this fundamental type which runs through all his in-
struments from first to last ? The reason is given in his own
first memoir (p. 51), " How could a single instrument repro-
duce at once the total actions of all the organs operated in human
speech? This was ever the cardinal question!' Eeis con-
structed his instrument therefore with intent to reproduce
human speech. For this reason he borrowed from the ear
the suggestion of a tympanum. Of the operation of the tym-
.panum he had the most exact and perfect conception. He
says (p. 54), " Every tone, and every combination of tones " —
and this includes articulate tones, of course, and is just as
true of them as of any other kind — " evokes in our ear, if it
enters it, vibrations of the drum-skin, the motions of which may
le represented ly a curve!' And further : " As soon, therefore, as
it shall become possible, at any place and in any prescribed manner,
to set up vibrations whose curves are like those of any given
tone, or combination of tones, we shall then receive the same im-
pression as that tone or combination of tones would have pro-
duced upon us!' Again, it is clear that his study of acoustics
led him to employ the tympanum, because of its special value
in responding to all the complex vibrations of human speech.
It is no less significant that when a decade later Varley,
Gray, and Bell, set themselves to invent tone-telephones for
the purpose of multiple telegraphy, they abandoned tympa-
nums as being unsuitable for tone-telephones, and in lieu

INVENTOR OF THE TELEPHONE. 43

thereof employed vibrating tongues like those of tuning-
forks. Eeis's use of the tympanum had a very definite
meaning then ; it meant nothing less than this : I intend my
instrument to transmit any sound that a human ear can
hear. That it was explicitly within his intention to transmit
speech is confirmed by another passage of his first memoir
(p. 58), wherein he remarks with a shade of disappointment
that though " the consonants are for the most part tolerably
distinctly reproduced, the vowels are not yet to an equal
degree." To his own pupils and co-workers he communi-
cated his ideas. One of the former, Mr. E. Horkheimer, now
of Manchester, expressly says (see p. 117) that Eeis's inten-
tion was to transmit speech, and that the transmission of
music was an afterthought adopted for the convenience of
public exhibition, just as was the case with the public exhi-
bitions of Bell's Telephone fifteen years later.

Nor did this imperfection cause Eeis to hide his intentions
from the world. He modestly claimed such success as he ,
had obtained, and left the rest. In 1863 he drew up a
Prospectus (given in extenso on p. 85), which was printed to
accompany the instruments 4which were sold ; and of which
copies are still extant. In this document he says : " Besides
the human voice, according to my experience, there can
also be reproduced the tones of good organ pipes, from F
to c, and those of a piano." In this same Prospectus
(p. 87) occur the instructions for the use of the signal call
by which the listener communicates his wishes to the speaker.
Those instructions run : " One beat = sing ; two beats =
speak." Can any sane person doubt that Eeis intended his
instrument to transmit speech, when such directions stand
printed in his own Prospectus ? Legat's Eeport (1862)
speaks of Eeis's instrument as intended (see p. 77) to speak,
and further describes the use of an elliptic cavity to which
the listener can apply his ear. Kuhn (1866) (see p. 106) says

44 PEILIPP REIS,

that the square-box transmitter (Figs. 17, 18) did not send
speech well, and complains that he could only get from it an
indistinguishable noise. Doubtless he spoke too loudly.
Pisko (1865) speaks of the Eeis instrument as intended for
speaking (p. 105). Further, in the letter which Eeis wrote
in 1863 to Mr. W. Ladd, of London, he expressly emphasises
by underscoring the word that his Telephone can transmit
"any sound" that is sufficiently loud, and he refers to the
speaker and listener at the two ends of the line as " the cor-
respondents." The only reply henceforth possible to any
person who shall assert that Keis's Telephone was not ex-
pressly intended to transmit articulate speech is the good
honest retort : impudentissime mentiris.

II. — Reis's Telephone, in the hands of Reis and his
contemporaries, did transmit speech.

Of the performance of his instruments Eeis speaks modestly
and carefully, nothing extenuating of his failures, nothing
exaggerating of his successes. I shall not attempt to be
wiser than he ; nor seek to make out his instrument to have
been either more perfect or more reliable than he himself
knew it to be. The membrane tympanum of his transmitter
was liable to become relaxed by the moisture of the breath
rendering the instrument — as Graham Bell found fifteen
years later with his membrane magneto-transmitters — uncer-
tain in its action. Moreover, in some earlier forms of Eeis's
transmitter, notably those with a vertical tympanum, the
adjustment of the contact-points that controlled the current
was a matter of delicacy requiring experience and practice,
so that casual experimenters failed to obtain the results
which Eeis himself obtained ;* they obtaining only a noisy

* Mr. E. Albert, of the firm of J. W. Albert and Sohn, of Frankfurt,
to whom Keis entrusted the manufacture of Telephones for public sale, thus
writes : " The most important part was the membiane, because the delicacy

INVENTOR OF TEE TELEPHONE. 45

snarl where he obtained intelligible speech. Lastly, the
very delicacy of the essential parts, the conducting strips of
metal which lay lightly in contact against one another, mili-
tated against a uniformity of success when tried with dif-
ferent voices, some of wmVh were too low to produce any
effect, others so loud as to rattle the delicate contact-pieces in
a manner fatal to the attainment of the desired result.

In spite of all these drawbacks, which were not inherent in
the principle of the instrument, there is plenty of evidence
that Reis's Telephone did transmit speech. Eeis himself records
this fact :

(1.) In 1861, in his memoir ' On Telephony ' (see p. 58),
" The consonants are for the most part tolerably distinctly re-
produced, lut the vowels not yet in an equal degree"

(2.) In his ' Prospectus ' (p. 86) Eeis says that the tones of
organ-pipes and of the piano can be reproduced as well as
the tones of the human voice, " according to my experience."

(3.) The fact is attested by Inspector Wilhelm von Legat,
in his Keport in the ' Zeitschrift ' (p. 77), 1862. After alluding
to the indistinctness of the vowels, he says : " Single words,
uttered as in reading, speaking, and the like, were perceptible

of the apparatus depended principally upon that part. As it was not
possible to make every membrane equally good, so it came about that
instruments of different degrees of superiority came into use, and various
decisions were arrived at as to the ability of the instrument to perform
the functions for which it was designed. Those who happened to have a
poor instrument were able to hear but little ; while those who possessed a
good instrument were astonished at its performances. A good instrument
reproduced the words sung into it in such a manner that not only the
pitch but also the words of the song were perfectly understood, even when
the listener was unacquainted with the song and the words."

M. St. Ed me, of Paris, who contributed to ' Cosmos,' vol. xxiv. p. 349,
1864, an article on Reis's Telephone, of which he had seen an example in
Konig's atelier, said that when the scale was sung it needed a trained ear
to distinguish the notes amidst the noises of the receiver. He must have
got hold of an uncommonly bad transmitter with a flabby tympanum to
have failed so completely.

46 PH1LIPP REIS,

indistinctly, nevertheless, here also the inflexions of the voice, the
modulations of interrogation, exclamation, wonder, command, etc.,
attained distinct expression"

(4.) Professor Quincke, of Heidelberg, testifies (see p. 113)
that he heard and understood words spoken through a Reis
Telephone in 1864.

(5.) Professor Bottger, editor of the ' Polytechnisches Notiz-
blatt,' in 1863 says (see p. 90)': "The experimenters could
even communicate words to one another, though certainly
indeed, only such as had often been heard by them."

(6.) Dr. Eudolph Messel, an old pupil of Reis, and an eye-
witness of his early experiments, has written * : " There is
not a shadow of a doubt about Reis having actually achieved
imperfect articulation. I personally recollect this very distinctly,
and could find you plenty more people who witnessed the
same."

(7.) Herr Peter, a former colleague of Philipp Reis, whose
testimony will be found on page 126, narrates how he doubted
the powers of the instrument until he had verified them for
himself by speaking into it words which could not possibly
be premeditated.

(8.) Mr. E. Horkheimer, who aided Reis in his earlier work,
though he left Germany when the development of tfre
instrument was yet very far from complete, has even given
(see p. 117) a list of the words and expressions which he has
heard transmitted by the earlier forms of the instrument.

(9.) Herr Philipp Schmidt, brother-in-law of Philipp Reis,
and now acting-paymaster in the Imperial German Navy at
Wilhelmshavn, says : " he succeeded finally in reproducing at
a distance, words and whole sentences." " There never was
any understanding between my brother-in-law and myself as

* Letter of Dr. Messel to Professor W. F. Barrett quoted, in Professor
Barrett's memoir, ' On the Electric Telephone,' read Nov. 19, 1877, to the
Dublin Royal Society. Vide Proc. Boy. Soc. Dubl. 1877.

INVENTOR OF THE TELEPHONE. 47

to particular words and sentences: on the contrary, these
were quite spontaneous."

(10.) Mr. S. M. Yeates, of Dublin, who in 1865 constructed
a modified Eeis Telephone (see p. 128), has thus described the
performance of the instrument : " Before disposing of the
apparatus, I showed it at the November meeting (1865) of
the Dublin Philosophical Society, when both singing and
the distinct articulation of several words were heard through it,
and the difference letween the speakers' voices clearly recognised!' *

It is difficult to conceive how testimony on this point could
be stronger. From so many different sources it is alike
agreed that — with the instrument presumably in good
adjustment — Eeis's Telephone, in the hands of Eeis and his
contemporaries, did transmit articulate speech.

III. — Reis's Telephone will transmit speech.

Eeis's Telephone consists of two parts : a " transmitter,"
into which the speaker speaks; and a "receiver," at which
the hearer listens. Their various forms have been described
in detail in the preceding chapter. All that we are con-
cerned with at this place is, whether these instruments will
at the present day do what is asserted. The writer has
tested every form of Eeis's transmitter, save only some of the
tentative historic forms shown in Figs. 2-8, 13, 15, & 16, ante,
and has found them perfectly competent to transmit speech,
provided proper precautions were taken : namely, that the
contacts were clean and in adjustment, that the tympanum
was tightly stretched, and that the speaker did not speak too
loudly : f in other words, that the instruments were properly
used. Any one who wants not to succeed in transmitting
speech with Eeis's transmitter has only to neglect these
reasonable precautions. It is not, therefore, difficult to fail.

* See Barrett's ' Telephones Old and New ' (1878), p. 12.
f See Reis's own remark at bottom of p. 57.

48 PEILIPP EEIS,

The writer has also tested both the better-known forms of
Keis's receiver (Figs. 21, 22, & 23), and finds that both are
perfectly competent to receive speech electrically and repro-
duce it audibly, both vowels and consonants being perfectly
distinct and articulate, though never as loud as in more
modern forms of telephone-receiver. From a steel wire,
magnetised, as prescribed by Eeis, by surrounding it with a
coil of wire through which the current passes, the writer has
obtained articulation exceeding in perfection of definition,
both of vowels and of consonants, the articulation of any other
telephone-receiver he has ever listened to. Perhaps it may
be objected that it is difficult to listen to a steel wire. Eeis
met this difficulty in his own way by mounting his steel wire
upon a small sounding-box to strengthen the sounds, and
added a flat upper case against which the ear of the listener
can be pressed, and which can be removed, or opened as a
lid, when a whole audience is to hear simultaneously the tones
of the instrument when working in a loud and disagreeable
manner, as a transmitter of the coarser vibrations of a loudly
sung melody. The lid is not wanted for this latter purpose —
is an encumbrance; which, nevertheless, by its presence
proves the more delicate functions of the instrument. Eeis's
instructions in his ' Prospectus/ p. 86, are that pressing this
lid down firmly upon the steel core increases the loudness of
the sounds. Any one who wants not to succeed in receiving
speech with Eeis's receiver has, as before, only to neglect
reasonable precautions. He has only to use an imperfect or
bad transmitter, or use it carelessly, or put the receiver to a
sufficient distance from his ear, to attain this result. There
are people who have failed to make Eeis's receiver receive.

This is not the place to discuss a doctrinaire objection
sometimes raised, that it is theoretically impossible for Eeis's
instruments to work. For the moment we are concerned
with the practical question : Do they work ? No one

INVENTOR OF THE TELEPHONE. 49

practically experienced in telephones, even if he should
deny that Eeis had any such intention, will dispute that
they can now be made to transmit speech. Professor Dolbear,
himself no mean authority on telephones, testifies, as quoted
above (p. 41), "that the instruments would talk, and would
talk well" He would, indeed, be a bold man who would
come forward to deny what can be shown any day as an
experimental fact : that Rds's Telephone will transmit speech.

We have now shown that Philipp Eeis was the undisputed
inventor of an instrument which he called the Telephone,
which instrument can now be used to transmit speech ; which
was then used to transmit speech ; and which was invented
on purpose to transmit speech. So far the result of the
examination into the facts of the case is conclusive enough.
A more complete case could hardly be desired. No honest
person could hesitate for want of proof, either greater in
amount or more direct to the point.

Nevertheless, I propose in another section to go a little
further and to prove a technical point of highest interest ;
namely, that there is not in the Telephone Exchanges of
England to-day, any single telephone to be found in which
the fundamental principles of Eeis's Telephone are not the
essential and indispensable features. These considerations
being, however, of a strictly technical nature, will be best
considered in an Appendix. As, however, we are able to
show that those instruments which are now in daily use for
transmitting speech, embody the two fundamental principles
upon which Eeis based the instrument which he called " Das
Telephon" it would be dishonest to the memory of the
deceased inventor to claim anything less than that he was
the " first and true inventor " of the Telephone.

50 PHILIPP RE1S,

CHAPTER IV.

CONTEMPORARY DOCUMENTS.

THE following documents, drawn from the scientific literature
of the time, are placed in chronological order, beginning with
the first memoir published by Philipp Reis himself, in the
Jaliresbericht of the Physical Society of Frankfort, for th,e
year 1860-61. Every care has been taken that the trans-
lations here given shall be faithful in every detail to the
originals. All notes and comments by the translator are
distinguished by being enclosed in square brackets.

[1.] ON TELEPHONY BY THE GALVANIC CURRENT.
By PHILIPP REIS.

[Translated from the Annual Report (Jahresbericht) of the Physical
Society of Frankfurt am-Main, for 1860-1861.]

THE surprising results in the domain of Telegraphy, have
often already suggested the question whether it may not also
be possible to communicate the very tones of speech direct to
a distance. Researches aiming in this direction have not,
however, up to the present time, been able to show any
tolerably satisfactory result, because the vibrations of the
media through which sound is conducted, soon fall off so
greatly in their intensity that they are no longer perceptible
to our senses.

A reproduction of the tones at some distance by means of

INVENTOR OF THE TELEPHONE. 51

the galvanic current, has perhaps been contemplated ; but at
all events the practical solution of this problem has been
most doubted by exactly the very persons who by their
knowledge and resources should have been enabled to grasp
the problem. To one who is only superficially acquainted
with the doctrines of Physics, the problem, if indeed he
becomes acquainted with it, appears to offer far fewer points
of difficulty because he does not foresee most of them. Thus
did I, some nine years ago (with a great penchant for what
was new, but with only too imperfect knowledge in Physics),
have the boldness to wish to solve the problem mentioned ;
but I was soon obliged to relinquish it, because the very first
inquiry convinced me firmly of the impossibility of the
solution.

Later, after further studies and much experience, I perceived
that my first investigation had been very crude and by no
means conclusive : but I did not resume the question seriously
then, because I did not feel myself sufficiently developed to
overcome the obstacles of the path to be trodden.

Youthful impressions are, however, strong and not easily
effaced. I could not, in spite of every protest of my reason,
banish from my thoughts that first inquiry and its occasion ;
and so it happened that, half without intending it, in many a
leisure hour the youthful project was taken up again, the diffi-
culties and the means of vanquishing them were weighed, —
and yet not the first step towards an experiment taken.

How could a single instrument reproduce, at once, the
total actions of all the organs operated in human speech ?
This was ever the cardinal question. At last I came
by accident to put the question in another way : How
does our ear take cognizance of the total vibrations of all the
simultaneously operant organs of speech ? Or, to put it more
generally: How do we perceive the vibrations of several
bodies emitting sounds simultaneously ?

E 2

52 PHILIPP REIS,

In order to answer this question, we will next see what
must happen in order that we may perceive a single tone.

Apart from our ear, every tone is nothing more than the con-
densation and rarefaction of a body repeated several times in a
second (at least seven to eight times *). If this occurs in the
same medium (the air) as that with which we are surrounded,
then the membrane of our ear will be compressed toward the
drum-cavity by every condensation, so that in the succeeding
rarefaction it moves back in the opposite direction. These
vibrations occasion a lifting-up and a falling-down of the
" hammer " [malleus bone] upon the " anvil " [incus bone]
with the same velocity, or, according to others, occasion an
approach and a recession of the atoms of the auditory
ossicles, and give rise, therefore, to exactly the same number
of concussions in the fluid of the cochlcea, in which the
auditory nerve and its terminals are spread out. The greater
the condensation of the sound-conducting medium at any
given moment, the greater will be the amplitude of vibration
of the membrane and of the " hammer," and the more power-
ful, therefore, the blow on the " anvil " and the concussion of
the nerves through the intermediary action of the fluid.

The function of the organs of hearing, therefore, is to impart
faithfully to the auditory nerve, every condensation and
rarefaction occurring in the surrounding medium. The
function of the auditory nerve is to bring to our consciousness
the vibrations of matter resulting at the given time, both
according to their number and their magnitude. Here, first,
certain combinations acquire a distinct name : here, first the
vibrations become musical tones or discords (Misstone).

That which is perceived by the auditory nerve, is, therefore,

* [This was the number formerly accepted on the authority of Despretz
as the minimum number of vibrations that could evoke the sensation of a
tone in the human ear. The limit now more usually recognized is that of
Helmholtz, who assigns from thirty to forty double vibrations per second
as the minimum.] — S. P. T.

INVENTOR OF THE TELEPHONE. 53

merely the action of a force affecting our consciousness, and as
such may be represented graphically, according to its duration
and magnitude, by a curve.

Fig. 24.

Let the line a, b, indicate any given length of time, and
the curve above the line a condensation ( + ), the curve below
the line a rarefaction ( — ), then every ordinate erected at the
end of an abscissa will give [according to the height of it], at
a moment indicated by the position of the foot of the
ordinate, the strength of the condensation that is causing the
drum- skin to vibrate.

Our ear can perceive absolutely nothing more than is
capable of being represented by similar curves, and this
method is completely sufficient to bring before our clear
consciousness every tone and every combination of tones.

If several tones are produced at the same time, then the
medium that conducts sound is placed under the influence of
several simultaneous forces ; and the two following laws
hold good : —

If all the forces operate in the same sense, the resultant
motion is proportional in magnitude to the sum of the forces.

If the forces operate in opposite senses, the resultant
motion is proportional in magnitude to the difference of the
opposing forces.

Let us exhibit the condensation-curves for three tones —
each singly (Table I.)* : then, by adding together the ordinates

* [The three plates or tables with which Keis accompanied his Memoir,
containing a variety of undulatory curves corresponding to various com-
binations of tones, both of musical concords and of dissonant sounds, are
not reprinted in this book in their entirety. Table I. contained three sets,
the first of which is reproduced by photo-lithography in reduced facsimile

54 PHILIPP REIS,

corresponding to equal abscissae, we can determine new
ordinates and develop a new curve which we may call the
combination-curve [or resultant curve]. Now this gives us
just exactly what our ear perceives from the three simul-
taneous tones. It ought to cause us as little wonder that
a musician can recognize the three tones, as that (as is the
fact) a person conversant with the science of colour, can
recognize in green, blue and yellow tints. The combination-
curves of table I. present, however, very little difficulty, since
in them all the proportions of the component curves recur
successively. In chords consisting of more than three tones
(Table II.), the proportions of the components are no longer
so easy to recognize in the drawing. But it is also difficult
to an accomplished musician, in such chords to recognize the
individual notes.

Table III. shows us a discord. Why discords affect us so
unpleasantly I leave provisionally to the contemplation of
the gentle reader, as I may perhaps return to this point in
another memoir.

It follows from the preceding that : —

(1.) Every tone and every combination of tones evokes in
our ear, if it enters it, vibrations of the drumskin, the motions
of which may be represented by a curve.*

(2.) The motions of these vibrations evoke in us the per-
ception (sensation) of the tone: and every change in the
motion must change the sensation.

in Fig. 47, p. 173. It was also reproduced by W. von Legat in his
Report from which Plate I. at end of this book is copied, Fig. 1 of that
plate being the same as Fig. 1 of Eeis's Table I. Fig. 2 of Plate 1, was
in like manner copied by Legat from the first figure of Reis's Tahle II., and
Fig. 3 of Plate I., which represents the curves of a non-harmonious com-
bination is the same as Reis's Table III., the only difference being that in
Reis's Table III. the irregular undulations of the resultant curve were
emphasised by being labelled ' Dissonanz.'] — S. P. T.

* [This is true for speech-tones as well as for musical tones. Each kind
of tone may be represented by its own characteristic curve.] — S. P. T.

INVENTOR OF THE TELEPHONE.

As soon, therefore, as it shall be possible at any place and
in any prescribed manner, to set up vibrations whose curves
are like those of any given tone or combination of tones, we
shall receive the same impression as that tone or combina-
tion of tones would have produced upon us.*

Taking my stand on the preceding principles, I have suc-
ceeded in constructing an apparatus by means of which I am
in a position to reproduce the tones of divers instruments,
yes, and even to a certain degree the human voice. It is
very simple, and can be clearly explained in the sequel, by
aid of the figure :

f - ' ' 4

In a cube of wood, r s t u v w x, there is a conical hole, a,
closed at one side by the membrane b (made of the lesser
intestine of the pig), upon the middle of which a little strip
of platinum is cemented as a conductor of the current [or
electrode]. This is united with the binding-screw, p. From

* [This is the fundamental principle, not only of the telephone, but ot
the phonograph ; and it is wonderful with what clearness Reis had grasped
his principle in 1861.]— S. P. T.

56 PHILIPP REIS,

the binding-screw n there passes likewise a thin strip of
metal over the middle of the membrane, and terminates here
in a little platinum wire which stands at right angles to the
length and breadth of the strip.

From the binding-screw, p, a conducting-wire leads
through the battery to a distant station, ends there in a spiral
of copper-wire, overspun with silk, which in turn passes into
a return-wire that leads to the binding-screw, n.

The spiral at the distant station is about six inches long,
consists of six layers of thin wire, and receives into its middle
as a core a knitting-needle, which projects about two inches
at each side. By the projecting ends of the wire the spiral
rests upon two bridges of a sounding-box. (This whole piece
may naturally be replaced by any apparatus by means of
which one produces the well-known " galvanic tones.")

If now tones, or combinations of tones, are produced in the
neighbourhood of the cube, so that waves of sufficient strength
enter the opening a, they will set the membrane I in vibra-
tion. At the first condensation the hammer-shaped little
wire d will be pushed back. At the succeeding rarefaction
it cannot follow the return- vibration of the membrane, and
the current going through the little strip [of platinum]
remains interrupted so long as until the membrane, driven by
a new condensation, presses the little strip (coming from p)
against d once more. In this way each sound-wave effects
an opening and a closing of the current.

But at every closing of the circuit the atoms of the iron
needle lying in the distant spiral are pushed asunder from
one another. (Muller-Pouillet, ( Lehrbuch der Physik/ see
p. 304 of vol. ii. 5th ed.). At the interruption of the current
the atoms again attempt to regain their position of equili-
brium. If this happens then in consequence of the action
and reaction of elasticity and traction, they make a certain

INVENTOR OF THE TELEPHONE. 57

number of vibrations, and yield the longitudinal tone * of the
needle. It happens thus when the interruptions and restora-
tions of the current are effected relatively slowly. But if these
actions follow one another more rapidly than the oscillations
due to the elasticity of the iron core, then the atoms cannot
travel their entire paths. The paths travelled over become
shorter the more rapidly the interruptions occur, and in pro-
portion to their frequency. The iron needle emits no longer
its longitudinal tone, but a tone whose pitch corresponds to
the number of interruptions (in a given time). But this is
saying nothing less than that the needle reproduces the tone
which was imparted to the interrupting apparatus.

Moreover, the strength of this tone is proportional to the
original tone, for the stronger this is, the greater will be the
movement of the drum-skin, the greater therefore the move-
ment of the little hammer, the greater finally the length of
time during which the circuit remains open, and consequently
the greater, up to a certain limit, the movement of the atoms
in the reproducing wire [the knitting needle], which we
perceive as a stronger vibration, just as we should have
perceived the original wave.

Since the length of the conducting wire may be extended
for this purpose, just as far as in direct telegraphy, I give to
my instrument the name " Telephon."

As to the performance attained by the Telephone, let it
be remarked, that, with its aid, I was in a position to
make audible to the members of a numerous assembly (the
Physical Society of Frankfort-on-the-Main) melodies which
were sung (not very loudly) into the apparatus in another
house (about three hundred feet distant) with closed doors.

Other researches show that the sounding-rod [i.e. the

* [That is, at any single demagnetisation of the needle, it vibrates and
emits the same tone as if it had been struck or mechanically caused to
vibrate longitudinally.] — S. P. T.

58 PHILIPP REIS,

knitting needle] is able to reproduce complete triad chords
(" Dreiklange ") of a piano on which the telephone [i.e. the
transmitter] stands ; and that, finally, it reproduces equally
well the tones of other instruments — harmonica, clarionet,
horn, organ-pipes, &c., always provided that the tones belong
to a certain range between F and / *.

It is, of course, understood' that in all researches it was
sufficiently ascertained that the direct conduction of the sound
did not come into play. This point may be controlled very
simply by arranging at times a good shunt-circuit directly
across the spiral [i.e. to cut the receiving instrument out of
circuit by providing another path for the currents of elec-
tricity], whereby naturally the operation of the latter
momentarily ceases.

Until now it has not been possible to reproduce the tones
of human speech with a distinctness to satisfy everybody.
The consonants are for the most part tolerably distinctly
reproduced, but the vowels not yet in an equal degree. Why
this is so I will endeavour to explain.

According to the researches of "Willis, Helmholtz, and
others, vowel sounds can be artificially produced by causing
the vibrations of one body to reinforce those of another
periodically, somewhat after the following scheme : —

An elastic spring is set in vibration by the thrust of the

Fig. 26.

tooth of a cog-wheel : the first swing is the greatest, and
each of the others is less than the preceding one (see Fig. 26)

* [This range was simply due to the degree of tension of the tympanum ;
another tympanum differently stretched, or of different proportions, would
have a different range according to circumstances.]— S. P. T.

INVENTOR OF THE TELEPHONE. 59

After several vibrations of this sort (without the spring
coming to rest) let another thrust be given by the tooth ; the
next swing will again be a maximum one, and so on.

The height or depth of the sound produced in this fashion
depends upon the number of vibrations made in a given
time ; but the quality of the note depends upon the number
of variations of amplitude (Anschwellungen) occurring in the
same time.

Two vowels of equal pitch may be distinguished from each
other somewhat after the manner represented by the curves
(1) (2) : while the same tone devoid of any vowel quality, is
represented by curve (3).

• Fig. 27.

Our organs of speech create the vowels probably in the
same manner by a combined action of the upper and lower
vocal chords, or of the latter and of the cavity of the mouth.

Now my apparatus gives the number of the vibrations,
but with far less strength than the original ones ; though
also, as I have cause to think, always proportional to one
another up to a certain degree. But because the vibrations
are throughout smaller, the difference between large and small
vibrations is much more difficult to recognize than in the
original waves, and the vowel is therefore more or less
indefinite.

60 PEILIPP EEIS,

Whether my views with respect to the curves representing
combinations of tones are correct, may perhaps be deter-
mined by aid of the new phonautograph described by
Duhamel. (See Yierordt's ' Physiology/ p. 254.)

There may probably remain much more yet to be done for
the utilisation of the telephone in practice (zur praktischen
Verwerthung des Telephons). For physics, however, it has
already sufficient interest in that it has opened out a new
field of labour.

PHILIPP EEIS.

Friedrichsdorf, near Frankfort-on- the- Main,
in December 1861.

[Though the foregoing memoir, as printed in the ' Jahres-
bericht/ of the Physical Society of Frankfort-on-the-Main,
is dated "December 1861," it was delivered verbally on
October 26th preceding, as the ' Proceedings ' of the Society
show. From the ' Jahresbericht ' for the succeeding year we
learn that three weeks after the delivery of this communi-
cation Eeis made a second communication to the Society on
a kindred matter. The entry is as follows (' Proceedings f x>f
the Society, p. 13) : "On the 16th November, by the same:
Explanation of a new Theory concerning the Perception of
Chords and of Timbre (' Klangfarben '), as a Continuation and
Supplement of the Memoir on the Telephone." So far as can
now be learned, the substance of this communication was
embodied in the latter part of the paper " On Telephony,"
when written out in December for publication. On the 8th of
January, 1862, the formal thanks of the Society were voted
to Eeis for the manuscript which he had contributed to the
' Jahresbericht/

It is of interest, moreover, to note that the matter did not
immediately drop. Professor Bottger, who as one of the
regular lecturers of the Physical Society, held fortnightly dis-

INVENTOR OF THE TELEPHONE. 61

courses on matters of scientific novelty, took occasion on the
7th of December to recur to the subject then attracting so
much attention. The title of his discourse (see ' Proceedings '
of the Society, p. 11) was " Application of an Experiment
relating to the Transmission of Musical Tones to any desired
distance by means of the Galvanic Current." It is not quite
certain whether Reis was present on this occasion. Early in
the spring of 1863, appeared in Bottger's ' Polytechnisches
Notizblatt' (No. 6 of that year) an article which contains in
condensed form Bottger's discourse. This article was copied
into Dingler's 'Polytechnisches Journal' for May 1863.
vol. clxviii.p. 185, and also into the 'Polytechnisches Central-
blatt' for July 1863, vol. xxix. p. 858. An extract of Reis's
own paper, condensed from the ' Jahresbericht ' by Dr. Roeber
(now President of the Physical Society of Berlin), appeared
in the ' Berliner Berichte ' (i. e. the ' Fortschritte der Physik ')
for 1861, vol. xvii. pp. 171-173. It is interesting to note
that Reis's paper was then deemed worthy to stand in the
pages of the ' Fortschritte ' by the side of the classic researches
of Thomson on Regelation, and of Maxwell on Magnetic
Lines of Force. The following is a translation of Bottger's
notice mentioned above.]

[2.] ON THE TRANSMISSION OF TONES TO A DISTANCE AS
FAR AS DESIRED, BY THE HELP OF ELECTRICITY (TELEPHONY).

[Translated from the original notice by Professor Bottger, which ap-
peared in Bottger's * Polytechnischen Notizblatt,' 1863, No. 6, p. 81, in
Dingler's * Polytechnisches Journal,' 1863, vol. clxviii. p. 185, and in the
1 Polytechnisches Centralblatt,' 1863, t. xxix. p. 858.]

Two decades ago we had not yet gone beyond the first
attempts to give signals at a great distance by the aid of
electricity. Since then telegraphy has attained such a com-
pleteness, and the telegraph wire has reached such a universal
extension, that there seems little left for even the boldest
wish to desire.

62 PHILIPP EEIS,

Now there crops up a first serious research to reproduce
tones at any desired distance by the aid of electricity. This
first experiment which has been crowned with some success,
has been made by the teacher of Natural Science at Fried-
richsdorf, not far from Frankfort-on-the-Main, Herr Ph. Eeis,
and has been repeated in the Auditorium of the Physical
Society in Frankfort, before numerous assembled members on
the 26th of October, 1861. He caused melodies to be sung
not very loudly into one part of his apparatus, which was
placed in a building (the Burger-Hospital), about 300 feet
distant, with closed windows and doors. These same melodies
were audible to the members in the meeting-hall by means of
the second part of the apparatus. These wonderful results
were attained with the following simple pieces of apparatus.
A little light box, a sort of hollow cube of wood, has a large
opening at its front side, and a small one at the back on the
opposite side. The latter is closed with a very fine membrane
(of pig's smaller-intestine) which is strained stiff. A narrow
springy strip of platinum foil, fixed at its outer part to the
wood, touches the membrane at its middle ; a second platinum
strip is fastened by one of its ends to the wood at another
spot, and bears at its other end a fine horizontal spike, which
touches the other little platinum strip where it lies upon the
membrane.

As is known, tones arise from rarefactions and condensa-
tions of the air following quickly after one another. If these
motions of the air, known as waves, strike upon the thin
membrane, they press it against the little plate of platinum
with which it is in contact, and immediately let it vibrate
back again into the hollow cube (or so-called artificial ear) :
they act so that the membrane now takes a form hollowed
toward the cube, now bulged toward the outside. The little
plate of platinum touching it thereby acquires a vibrating
motion, so that it now is pressed against the spike of the
second [platinum plate], now leaves the same.

INVENTOR OF THE TELEPHONE. 63

If now one little plate of platinum be united by a wire
with one pole of a voltaic battery, and the electricity be led,
by a wire fastened to the other pole of the battery, to any
desired distance ; there carried through a spiral, about six
inches long, made of a six fold winding of very thin covered
copper wire ; thence led back to the second platinum strip on
the wooden cube through a second insulated wire ; then at
every vibration of the membrane an interruption in the
current of electricity takes place because the platinum point
no longer touches the other little strip of platinum. Through
the hollow of the wire-spiral there is stuck a thin iron wire
(a strong knitting-needle), which is ten inches long, and
which rests upon two bridges of a sounding-board by its ends
which project on both sides about two inches out of the
spiral.

It is known * that if an electric current be led through a

* [The so-called "galvanic tone" heard on opening or closing the circuit
was well-known, and Wertheim had shown that this tone was, for any
given rod of iron, identical with its " longitudinal tone," i.e. the tone pro-
duced by striking it on the end so as to produce longitudinal vibrations.
But it was one of the most important discoveries in Reis's researches that
such a rod could take up any tone in obedience to the vibrations forced
upon it by periodic interruptions in the magnetising current in the spiral
of any degree of rapidity within very wide limits. The translator has had
occasion to examine this point, ar.d has found iron, steel, and cobalt wires
varying from 4 to 10 inches in length, including some used by Reis him-
self as receivers, to be capable of taking up vibrations from as slow as 40
per second to the very shrillest whistle audible to human ears, or exceeding
36,000 per second. It is sometimes also mistakenly supposed that such a wire
can respond only to the vibrations of tones that are musical, not to those
that are articulate, including both consonants and vowels. This, however,
is an entire mistake. For, using such a wire as a receiver (surrounded by its
proper coil and mounted with an appropriate sounding board, or, better still,
tympanum), in conjunction with a well-adjusted transmitter, the articula-
tion transmitted surpasses that obtainable with any of the ordinary mag-
netic receivers in distinctness, though not in loudness. This discovery of
Reis's is of the greatest importance, especially as some who ought to know
better have very unjustly denied the capability of this part of the apparatus
to act as a telephone receiver for articulate sounds.] — S. P. T.

64 PHILIPP EEIS,

spiral which surrounds an iron rod in the manner described,
at every interruption of the same a tone is audible arising
from the vibration of the rod. If the closings and interrup-
tions of the circuit follow one another relatively slowly, then
there is produced by the changes of position of the molecules
of the rod, evoked by the electricity, a tone, — the so-called
longitudinal tone of the rod, — which is dependent upon the
length and stoutness of the rod. But if the closings and
interruptions of the electric current in the spiral follow one
another more rapidly than the vibrations of the smallest
particles of the iron rod,* which vibrations are determined
by its elasticity, then these particles cannot complete their
paths, receive new impacts, their vibrations become smaller,
but quicker, and follow one another as frequently as the in-
terruptions. The iron rod then no longer gives its longi-
tudinal tone, but a tone, which is higher according as the
interruptions are more frequent in the given time, or lower,
as they are less frequent. It is known that the height and
depth of tones depends only on the number of air-waves
which follow one another in a second. We have seen
above that by this is determined the number of interrup-
tions of the electric current of our apparatus by means of
the membrane and the platinum strip. The iron wire must
therefore give out the tone in the same height or depth as
that which struck the membrane. Now since a very far
leading of the electricity makes it suffer scarcely any weak-
ening in proper apparatus, it is intelligible that one can
make the tone which acts on the membrane at one place
audible, by means of the iron rod, at any desired distance.

* [This limit is a mistake of Professor Bottger's. The longitudinal
tone of an unstrained iron or steel wire 10 inches long would be a note
about four octaves above the middle c of the piano ; whereas, in fact, any
note of the whole piano-gamut down to the lowest note, can be reproduced
by such a wire, as stated in preceding footnote.] — S. P. T.

INVENTOR OF THE TELEPHONE. 65

That the tone is made audible at a distance by the electric
agitations, and not by direct conduction of the sound-waves
through the wires is proved in the most evident way of all,
because one instantly hears no more the tone through the
spiral when a good short circuit is made, as, for example, by
laying upon the two wires which conduct the electricity a
strip of sheet metal right in front of the spiral.

The reproduced tones are, of course, somewhat weaker than
the original ones, but the number of vibrations is similar. If
thus the reproduction [of tones] in exactly similar height
and depth is easily attained, it is however difficult for our
ear, amidst the always smaller vibrations, to which the
diminished strength of the tone is due, to evaluate exactly
the magnitude of the vibrations. But the character of the
tone depends upon the number of variations of amplitude
(Anschwellungen), that is to say, depends upon whether, for
example, in the tones which have similar pitch and therefore
a similar number of waves per second, the fourth, sixth,
eighth, tenth, or sixteenth wave is stronger than the others.
For physicists have shown that an elastic spring is set in
vibration by the thrust of the teeth of a cog-wheel ; the first
vibration is the greatest, all those that follow being less. If
there comes, before the spring comes to rest, a fresh thrust
from a cog, then the next vibration is again equal to the
greatest first vibration without the spring making any more
vibrations on. that account ; and by this means vowel-tones
may be artificially produced.

One may also be yet far removed from being able to carry
on a conversation with a friend dwelling a hundred miles
distant, and recognise his voice, as if he sat near us ; but it
can no longer be maintained that this is impossible. Indeed
the probability that this will be attained * is already become

* [Professor Bottger had not to wait long for the fulfilment to a very
large degree of this anticipation; for within six months Dingler's Journal,

PEILIPP EEIS,

as great as the probability of the reproduction of natural
colours in photography has become through the notable
researches of Mepce.

[The second public exhibition which Eeis made of the
telephone was, like the first, in Frankfort-on-the-Main, but
this time before a Society known as the Freies Deutsches
Hochstift, or Free German Institute, a kind of Athenaeum
Club for the city of Frankfort, now for many years established
in the well-known house where the poet Goethe was born,
in the Grosse Hirschgraben. In 1862, however, the" Free
German Institute held its meetings in another building
known as the Saalbau. And on May the llth of that year
Philipp Eeis lectured upon and exhibited the Telephone.
A journal which appeared then, and still appears, in
Frankfort, with the title of ' Didaskalia,' devoted to light
literary and artistic news, popular science, and general in-
telligence of an informing character, ordinarily inserted
notices of the chief meetings of the Hochstift. On this occa-
sion a preliminary paragraph was inserted in the following
terms : — ]

[3.] TELEPHONY, i.e. SOUND-TRANSMISSION.

[TRANSLATION FROM ' DIDASKALIA,' MAY STH, 1862.]

The excellent physicist, Mr. Phil. Reis, of Friedrichsdorf,
calls by this name his surprising invention for using the
telegraph line to transmit really audible tones. Our readers
will perhaps remember having heard some time since of this

iu which this article appeared, contained Legat's report on Keis's instru-
ments, in which not only were various modifications in their construction
made known, but also the transmission of voice-tones, not yet perfectly
but with recognisable modulations and intonations, was recorded. Reis
had, indeed, succeeded nearly as well as this with his first instrument, as
his memoir of 1861 shows. See p. 58.]

INVENTOR OF TEE TELEPHONE. 67

invention, the first trials with which Mr. Eeis performed
here in the Physical Society. Since then the invention has
been constantly developed, and will, no doubt, become of
great importance.

[The lecture which followed this announcement was duly
given on the llth of May. In the Saalbau there is a suite
of four rooms. The Lecture to the assembled members of the
Hochstift was delivered in the Auditorium, at one end of
the suite : the wires were passed through the two intervening
rooms to the fourth chamber, where the transmitter was
placed, the doors being closed. The battery and wires were
borrowed from the Physical Society for this occasion, per-
mission for their use having .been granted on May 2nd,
as appears in a formal entry in the minute-book. The fol-
lowing notice of Eeis's discourse, believed to have been
written by Dr. Volger, Founder and first President of the
Hochstift, appeared in ' Didaskalia ' for May 14th.]

[4.] TRANSLATION FROM ' DIDASKALIA/ 12TH MAY, 1862.

Yesterday's meeting of the Free German Institute was a
very numerously attended one from the fact that the subject
in the order of business, " Telephony by Transmission of the
Galvanic Current," as explained by the inventor himself,
Mr. Phil. Eeis, excites so great an interest that it rightly
deserves the most general attention.

In a lecture exceedingly interesting, universally under-
stood, clear, and concise, Mr, Eeis gave a historical outline
of the origin and development of his idea of the practical
possibility of the transmission of tones in a galvanic way.

His first attempts were mostly unsuccessful in solving the
cardinal question propounded by him. " How is it possible
that a single instrument can reproduce at once the total action
of all the organs operated in human speech ? " Until finally
it occurred to him to seek the solution of the problem in the

68 PHILIPP EEIS,

question, "How does our ear take cognisance of the total
vibrations of all the organs of speech acting at once ? " or
" How do we perceive the vibrations of several bodies sound-
ing at once ? "

In order to answer this question the lecturer went more
closely into the anatomy of the ear and into the formation of
tones in general. After this was determined, he took up
again his experiments in reference to the transmission of
tones by means of galvanism.

Afterwards Mr. Eeis constructed considerably enlarged
the parts of the ear necessary for hearing, by which it was
finally possible for him to transmit the tones brought to the
mechanically-imitated ear.

The experiments by him some months ago in the Physical
Society, were, to the astonishment of all, exceedingly plain
and clear, whereas the experiment following the lecture of
yesterday was less successful. This was due partly to the
poor conductivity of the wires, partly to the locality.

Although much is still left to be done for the practical
utilisation (Verwerthung) of the telephone, yet a new and
interesting field of labour is hereby opened to physics.

[No more complete report than the foregoing is to be found,
and it is believed that the discourse, which like all those
given by Eeis was delivered extempore, was never committed
to writing. Its resemblance to the discourse of the preceding
autumn before the Physical Society is great ; and indeed it
may be said that all Reis's discourses upon the telephone
were practically identical in their contents. A few months
after this lecture, Reis presented a pair of instruments, trans-
mitter and receiver, to the Hochstift. These instruments
were not the same as those used by Reis at his lecture, but
were of the " improved " type, whilst those used by Reis at
his lecture to the Hochstift, were, so far as respects the trans-
mitter at least, more like the form described by W. von Legat,

INVENTOR OF THE TELEPHONE. 69

and figured in Plate II., Fig. A;* and according to Mr.
Horkheimer, who helped Eeis on this occasion, the trans-
mitter was provided with a conical mouthpiece of wood. The
transmitter presented later by Eeis is of the " square-box "
form (Fig. 17), and is stamped, " 1863, Philipp Eeis, 2,"
and the receiver is of the " knitting-needle " form (Fig. 23).
These instruments are carefully preserved by the Hochstift in
the " Goethehaus," amongst their archives " in everlasting
remembrance " of the inventor. A few months later, in 1863,
the Emperor of Austria and the late king Max of Bavaria
were residing at Frankfurt and visited the " Goethehaus ; "
and on this occasion Eeis's instruments were shown to these
distinguished visitors by the Founder and President of the
Hochstift, Dr. Volger.

In honour of his brilliant invention Eeis was, shortly
after his lecture, elected an honorary member of the Freies
Deutschcs Hochstift.]

[The next document in order is a Eeport by Wilhelm von
Legat, communicated to the Austro-German Telegraph Union
(Verein) in 1862, and printed in the ' Journal ' of that Society.
It was reprinted verbatim in Dingler's ' Polytechnisches
Journal,' for 1863, vol. clxix. p. 29. This Eeport is of great
importance. It is quoted by Graham Bell, in his earliest
account of his telephone. It was this Eeport, moreover,
which in 1875 or 1876, in a translated manuscript form, was
put into Mr. Edison's hands by the then President of the
Western Union Telegraph Company, and which formed the
starting-point of Edison's subsequent work.]

[* Compare * Die Geschichte und Entwickelung des Fernsprechwesens,'
a pamphlet issued officially in 1880 from the Imperial German Post-Office
in Berlin, p. 6.]

70 PH1LIPP &EIS,

[5.] ON THE KEPRODUCTION OF TONES IN THE ELECTRO -
GALVANIC WAY.

By v. LEGAT, Inspector of the Eoyal Prussian Telegraphs in

Cassel.

[Translated from the Journal of the Austro-German Telegraph Society
(edited by Dr. Brix), vol. ix. p. 125, 1862. (Zeitschrift des deutsch-
osterreichischen Telegraphen-Ve reins, 1862.)]

It might not be uninteresting to make known to wider
circles the following ideas concerning the reproduction of
tones in an electro-galvanic way, which have recently been
put forward by Herr Philipp Eeiss [sic] of Friedrichsdorf,
before the Physical Society, and before the meetings of the
Free German Institute (Freies Deutsches Hochstift) in
Frankfort-on-the-Main ; also to state what has hitherto been
attained in the realisation of this project, in order that
building upon the collected experiences and the efficacy of
the galvanic current, what has already been made service-
able to the human intellect for the advancement of its corre-
spondence, may in this respect also be turned to profit.

In what is here announced we are concerned not with the
action of the galvanic current in moving telegraphic apparatus
of whatever construction for producing visible signals, but
with its application for the production of audible signals — of
tones!

The air-waves, which by their action within our ears
awaken in us the sensation of sound, by first of all setting
the drum-skin into a vibrating motion, are thence, as is
known, conveyed to the inner part of the ear and to the
auditory nerves lying there by a lever apparatus of the
most marvellous fineness, — the auditory ossicles (including
" Hammer," " Anvil," and " Stirrup "). The experiment for
the reproduction of tones is based upon the following : viz.

INVENTOR OF THE TELEPHONE. 71

to employ an artificial imitation of this lever-apparatus and
to set it in motion by the vibrations of a membrane like the
drum-skin in the ear, and thus to open and close a galvanic
circuit which is united by a metallic conductor with a distant
station.

Before the description of the necessary apparatus is
followed out, it might be necessary, however, to go back to
the point how our ear perceives the vibrations of a given
tone, and the total vibrations of all the tones simultaneously
acting upon it ; because by this means will be determined
the various requisite conditions which must be fulfilled by
the transmitting and receiving apparatus for the solution of
the problem that has been set.

Let us consider first the processes which take place in
order that a single tone should be perceived by the human
ear ; so shall we find that each tone is the result of a condensa-
tion and rarefaction several times repeated in a certain period
of time. If this process is going on in the same medium
(the air) in which our .ear is situated, the membrane will at
every condensation be forced toward the hollow of the drum
and at every rarefaction will move itself in the opposite
direction.

These vibrations necessitate a similar motion of the auditory
ossicles, and thereby a transference to the auditory nerves is
effected.

The greater the condensation of a sound-conducting medium
at any given moment, the greater also will be tlje amplitude
of vibration of the membrane and of the auditory ossicles
and of their action ; and in the converse case the action will
be proportionally less. It is, therefore, the function of the
organs of hearing to communicate with fidelity to the auditory
nerves every condensation and rarefaction occurring in the
surrounding medium ; whilst it remains to be the function of
the auditory nerves to bring to our consciousness the number

72 PHILIPP REIS,

as well as the magnitude of the vibrations ensuing in a given
time.

Here in our consciousness a definite name is given to a
certain composition, and here the vibrations brought to the
consciousness become " tones."

That which is perceived by our auditory nerves is conse-
quently the effect upon our consciousness of a force which,
according to its duration and magnitude, may for the sake of
better comprehension, be exhibited graphically.

Let, for example, the length of the line a b be any definite
duration of time, and let the curves above this line denote
the condensations ( + ), and the curves below this line the

rarefactions ( — ) ; then every ordinate erected at the
extremity of an abscissa gives us the strength of the con-
densation in consequence of which the drum-skin vibrates,
at the moment indicated by the position of the foot of the
ordinate.

Anything more than that which is exhibited in this way
or by similar curves our ear cannot in the least perceive, and
this is sufficient to bring to our consciousness each single
tone and each given combination of tones. For, if several
tones are produced at the same time, the sound-conducting
medium is put under the influence of several simultaneously
acting forces which are subject to the laws of mechanics.

If all the forces operate in the same sense, then the
magnitude of the motion is proportional to the sum of the
forces. If the forces act in opposite directions, the magnitude
of the motion is proportional to the difference between the
opposing forces.

Consequently it is possible out of the condensation-curves
of several simultaneously-occurring tones to compound, by the

INVENTOR OF THE TELEPHONE. 73

foregoing principles, a condensation-curve which exactly
expresses that which our ear experiences on the reception of
these simultaneously-acting tones. The objection ordinarily
made to this, that a musician, or even any one, is able to
hear separately the single tones of which this combined
curve is built and constructed, cannot be admitted as a proof
to the contrary ; for one expert in the science of colour will,
for example, in the same way discern in green a mixture of
yellow and blue in their various shades : and the one
phenomenon equally with the other may be referred back
to this ; that, to the person concerned, the factors which make
up the product of that which reaches his consciousness are
well known.

According to that which has been already explained, it is
easy to construct the condensation-curves of various tones,
chords, &c., and for the sake of clearness some examples
follow : —

.Fig. 1, Plate I.,* shows a combination curve of three tones,
in which all the proportions of the components recur
successively.

Fig. 2 shows such a curve of more than three tones, in
which the proportions in the drawing can no longer so
evidently be given; yet the practised musician would here
recognise them, even although in practice it might be
difficult for him to single out, in such chords, the separate
tones.

This method of exhibiting the action of tones upon the
human ear offers the advantage of a very clear perception of
the process ; and that which is exhibited (Fig. 3) shows also
why a discord must affect our ear unpleasantly.

This apparent digression from the aim set forth was neces-
sary in order to indicate that as soon as it is possible for us
to create anywhere, and in any manner whatever, vibrations

* [Plate VIII. of the original in Vol. IX. of the Zeitschrift.j

74 PHILIPP ItEIS,

whose curves and magnitudes are similar to the vibrations of
any given tone, or of any given combination of tones, we
shall have the same impression as this original tone or this
original combination of tones would have produced upon us.

The apparatus hereafter described offers the possibility of
creating these vibrations in every fashion that may be desired,
and the employment of electro-galvanism gives us the
possibility of calling into life, at any given distance, vibra-
tions similar to the vibrations that have been produced, and
in this way to reproduce at any place the tones that have
been originated at another place.

In Fig. 4, Plate II.,* herewith presented, A is the trans-
mitter (Tonabgeber), and B the receiver (Tonempf anger),
which two instruments are set up at different stations. I
make, however, the preliminary remark that the manner of
joining the instruments for interchangeable use backward and
forward is here omitted for the sake of clearness, and the
more so because the whole is not here propounded as a final
fact, but in order to bring that which has been hitherto
accomplished to the knowledge of a wider circle. The
possibility of the working of the apparatus to a greater
distance than that which at present limits in practice the
direct working of the galvanic current may also be left out
of consideration, since these points may be easily rendered
possible by mechanical precautions, and do not affect the
essential part of the phenomena now described.

Let us next turn to the transmitter, Fig. A. It is put
into communication on one side with the metallic conductor
leading to the neighbouring station, and by means of this
with the receiver, Fig. B ; on the other side it is connected,
by means of the electro-motive power, C, with the earth or
a metallic return-conductor.

The transmitter, Fig. A, consists of a conical tube, a b, of
* [Plate IX. of the original Memoir.]

INVENTOR OF THE TELEPHONE. 75

about 15 centimetres length, 10 centimetres in the front,
and 4 centimetres in the back aperture.

(In the practical investigations it has been established that
the choice of material for this tube is without influence on
the use of the apparatus, and moreover a greater length of
the same for the certainty [of action] of the apparatus is
without effect. A greater width of the cylinder spoils the
usefulness of the apparatus ; and it is recommended that
the interior surface be as smooth as possible.)

The narrow hinder aperture of the cylinder is closed
by a membrane, o, of collodion, and on the middle of the
circular surface formed by this membrane rests one end, c,
of the lever, c d, the fulcrum (point of support), e, of which,
supported on a bearing, remains joined to the metallic
conductor.

The choice of the length of the two arms of the lever, c e
and e d, is determined by the laws of force of levers. It is
recommended that the arm, c e, be constructed longer than
the arm ed, in order to bring the smallest movement at c
into action at d with the greatest possible force ; but, on the
other hand, it is desirable to make the lever itself as light as
possible, in order that it may follow the motions of the mem-
brane. An uncertain following of the lever, c d} produces
impure tones at the receiving station. In the condition of
rest the contact, d g, is closed, and a delicate spring, n, holds
the lever firmly in this position of rest.

The second part of this apparatus, the pillar, /, consists of
a metallic support, which is united with one pole of the
battery, C, while the second pole of the battery is carried to
the metallic conductor of the other station.

Upon the support, /, there is a spring, g, with a contact,
which corresponds to the contact at d of the lever c d} and
whose position is regulated by a screw, h.

In order not to weaken the action of the apparatus by the

76 PH1LIPP REIS,

communication of the air- waves which are produced in using
the apparatus, against the back of the membrane, it is recom-
mended, in using the apparatus, to place over the tube, a I,
at right angles to its longitudinal axis, a screen of about
50 centimetres diameter, which fixes tight upon the outer
surface of the tube.

The receiver, Fig. B, consists of an electro-magnet, m m,
which reposes upon a sounding-box, u w, and whose wire
coils are respectively connected with the metallic conductor
and with the earth or metallic return-conductor.

Opposite the electro-magnet, m m, stands an armature,
which is connected with a lever, i, which is long as possible,
but light and broad.

The lever, i, is fastened, pendulum- wise, to the support, k,
and its movements are regulated by the screw, I, and the
spring, p.

In order to improve the action of the apparatus, this
receiver can be placed in one focus of an elliptically arched
cavity of corresponding size, in which case, then, the ear of
him who is listening to the reproduced tones may be placed
at the second focus of this cavity.

The action of the two apparatuses here described, is the
following : —

In a condition of rest the galvanic circuit is closed.

In the apparatus, Fig. A, by speaking (singing, or leading
into it the tones of an instrument) into the tube a b, in
consequence of the condensation and rarefaction of the air
present in this tube, there will be evoked a motion of the
membrane closing the tube at its narrow end, corresponding
to this condensation or rarefaction. The lever, c d, follows the
motion of the membrane, and opens and closes the galvanic
circuit at d g, so that by each condensation of the air in the
tube an opening, and at each rarefaction a closing of the
galvanic circuit ensues.

INVENTOR OF THE TELEPHONE. 77

In consequence of this process, the electro-magnet of Fig. B
(the receiver) will be demagnetised and magnetised correspond-
ingly with the condensations and rarefactions of the mass of air
in the tube A, a b [the mouth-piece of the transmitter], and the
armature belonging to the magnet will be set into vibrations
similar to those of the membrane in the transmitting
apparatus. The plank, i, connected with the armature,
conveys these similar vibrations to the air surrounding the
apparatus, Fig. B, which finally transmits to the ear of the
listener the tones thus produced.

We are not, therefore, dealing here with a propagation of
sound through the electric current, but only with a trans-
ference to another place of the tones that have been produced,
by a like cause being brought into play at this second place,
and a like effect produced.

Here, however, it must not be overlooked that the pre-
ceding apparatus reproduces, indeed, the original vibrations
in equal number, but that equal strength in the reproduced
vibrations has not yet been attained, and the production of
these is reserved for a completion of the apparatus.

One consequence of this temporary incompleteness of the
apparatus, is that the slighter differences of the original
vibrations are more difficult to discern : that is to say, the
vowel appears more or less indistinct, the more so since each
tone is dependent, not only on the number of vibrations of
the medium, but also on the condensation or rarefaction of the
same.

By this it is also explained, that, in the practical investiga-
tions heretofore carried on, chords, melodies, etc., were trans-
mitted with marvellous fidelity ; while single words uttered
as in reading, speaking, and the like, were perceptible more
indistinctly. Nevertheless, here also the inflexions of the
voice, the modulations of interrogation, exclamation, wonder,
command, &c., attained distinct expression.

78 PEILIPP EEIS,

There remains no doubt, that before expecting a practical
utilisation with serviceable results (praktische Verwerthung
mit Nutzen), that which has been here spoken of will require
still considerable improvement, and in particular mechanical
science must complete the apparatus to be used ; yet I am
convinced by repeated practical experiments that the prose-
cution of the subject here explained is of the highest
theoretical interest, and that our intelligent century will not
miss the practical utilisation (Verwerthung) of it.

[This article was also reprinted verbatim in Dingle r's
Polytechnisches Journal, vol. clxix. p. 29, 1863.]

[A peculiar interest is attached to the foregoing article,
partly on account of the unique nature of the instruments
therein described, partly because of the mystery attaching to
the author of the article. Wilhelm von Legat was Inspector
of the Eoyal Prussian Telegraphs at Cassel. How or when
he became acquainted with Philipp Eeis is not known — pos-
sibly whilst the latter was performing his year of military
service at Cassel in 1855. None of Eeis's intimate friends-or
colleagues now surviving can give any information as to the
nature of von Legat's relations with Eeis, as not even his
name is known to them, save from this Eeport. Yet he
was for one year only (1862), the year in which this Eeport
was made, a member of the Physical Society of Frankfort-on-
the-Main. It is possible that he may have been present at
Eeis's discourse in the preceding October. It is probable
that he was present at Eeis's subsequent discourse in May,
1862, to the Freies Deutsches Hochstift. Dr. Brix, then
editor of the ' Journal of the Telegraph Union/ informs me
that Inspector von Legat based his article upon information
derived direct from Eeis, whom he knew, and that the article
was submitted to Eeis before being committed to the ' Journal.'

INVENTOR OF THE TELEPHONE. 79

The particular form of transmitter described in von Legat's
Eeport (see also p. 25, ante) has also some important points
in common with that believed to have been used by Eeis at
the Hochstift. Neither of the specific forms described by In-
spector von Legat are now known to be extant. Inquiries
made in Frankfort and in Cassel have failed to find any trace
of them. Neither at the local Naturalists' Society, nor any-
where else in Cassel, did von Legat describe the invention.
He met with a tragic end during the Bavarian War in 1866,
in the battle near Aschaffenburg, having, according to some,
been shot, or, according to others, fallen from his horse.]

[The next extract is from an article entitled ' Telephonic,'
which appeared in a journal of science published at Leipzig,
under the title ' Aus der Natur.' This article is essentially a
paraphrase of Eeis's memoir read to the Physical Society in
the preceding December (see p. 50), and contains the same
illustrations, including a cut of the transmitter identical with
Fig. 9, p. 20.]

[6.] Aus DER NATUR. (Vol. xxi. 1862. July-October,
pp. 470-474.)

" Until now, however, it was not possible to reproduce
human speech with a distinctness sufficient for every person.
The consonants are mostly tolerably distinctly reproduced,
but the vowels not in an equal degree."

[About this time there arose a Correspondence in the
'Deutsche Industrie Zeitung' ('German Journal of Industry ')
concerning the telephone. In No. xvi. p. 184 (1863), a
correspondent who signs himself " K " asks whether the
account of the telephone is true ? In No. xviii. p. 208,
there is given a brief answer; and No. xxii. contains, on

80 PHILIPP REIS,

p. 239, an extract from Legat's Eeport, on Eeis's Telephone
(see p. 70 of this work), together with an editorial remark
to the effect that he had received a letter from Herr J. F.
Quilling, of Frankfort-on-the-Main, who gives the information
that in the transmission of singing in the telephone, the
singer could be recognized by his voice.]

[7.] [EXTRACT FROM THE ANNUAL EEPORT OF THE PHYSICAL
SOCIETY OF FRANKFORT-ON-THE-MAIN (1863).]

. . . .; "and on the 4th of July, 1863, by Mr. Philipp
Eeis, teacher, of Friedrichsdorf, On the Transmission of Tones
to any desired Distance, by the help of Electricity, with the
production of an Improved Telephone, and Exhibition of
Experiments therewith"

[This was Eeis's second occasion of bringing his Telephone
before the Physical Society. The instrument had now
assumed the " square-box " pattern described at p. 27 of this
work.]

[8.] LETTER OF PHILIPP EEIS.

[In July 1863, Mr. W. Ladd, the well-known instrument-
maker of London, bought one of Eeis's Telephones of Messrs.
J. W. Albert and Son of Frankfort. Philipp Eeis wrote to
Mr. Ladd the following letter of instructions, having heard
that Mr. Ladd proposed to exhibit the instrument at the
approaching meeting of the British Association. The auto-
graph letter, written in English, is still preserved, and has
been presented by Mr. Ladd to the Society of Telegraph
Engineers and of Electricians of London.]

INVENTOR OF THE TELEPHONE. 81

" Institut Garni or,

" Friedrichsdorf.

" DEAR SIR !

" I am very sorry not to have been in Francfort
when you were there at Mr. Albert's, by whom I have been
informed that you have purchased one of my newly-invented
instruments (Telephons). Though I will do all in my power
to give you the most ample explanations on the subject, I
am sure that personal communication would have been
preferable ; specially as I was told, that you will show the
apparatus at your next sientifical meeting and thus introduce
the apparatus in your country.

" Tunes * and sounds of any kind are only brought to our
conception by the condensations and rarefactions of air or
any other medium in which we may find ourselves. By every
condensation the tympanum of our ear is pressed inwards, by
every rarefaction it is pressed outward and thus the tympanum
performs oscillations like a pendulum. The smaller or greater
number of the oscillations made in a second gives us by help
of the small bones in our ear and the auditory nerve the idea
of a higher or lower tune.

" It was no hard labour, either to imagine that any other
membrane besides that of our ear, could be brought to make
similar oscillations, if spanned in a proper manner and if
taken in good proportions, or to make use of these oscillations
for the interruption of a galvanic current.

* [This word, as the context and ending of the paragraph shows, should
have been spelled tones. The letter, written in English by Eeis himself,
is wonderfully free from inaccuracies of composition ; the slip here noted
being a most pardonable one since the plural of the German " ton " is
" tonen" the very pronunciation of which would account for the confusion
in the mind of one unaccustomed to write in English. So far as is known,
this is the only piece of English composition ever attempted by Reis. —
S. P. T.]

82 PHILIPP REIS,

" However these were the principles wich (sic) guided me
in my invention. They were sufficient to induce me to try
the reproduction of tunes [i.e., tones — see footnote. — S. P. T.]
at any distance. It would be long to relate all the fruitless
attempts, I made, until I found out the proportions of the
instrument and the necessary tension of the membrane. The
apparatus you have bought, is now, what may be found most
simple, and works without failling when arranged carefully in
the following manner.

" The apparatus consists of two separated parts ; one for
the singing station A, and the other for the hearing station B.*

" The apparatus A, a square box of wood, the cover of
which shows the membrane (c) on the outside, under glass.
In the middle of the latter is fixed a small platina plate to
which a flattened copper wire is soldered on purpose to
conduct the galvanic current. Within the cercle you will
further remark two screws. One of them is terminated by a
little pit in which you put a little drop of quiksilver ; the
other is pointed. The angle, which you find lying on the
membrane, is to be placed according to the letters, with the
little whole [hole] (a) on the point (a) the little platina -foot
(b) into the quicksilver screw, the other platina foot will then
come on the platina plate in the middle of the membrane.

" The galvanic current coming from the battery (which I
compose generally of three or four good elements) is introduced
at the conducting screw near (b) wherefrom it proceeds to the
quicksilver, the movable angle, the platina plate and the com-
plementary telegraph tof the conducting screw (s). From

* [Reis here sketched a figure identical in all its parts with that which
a fortnight later was issued in his ' Prospectus.' His sketch is reproduced
in facsimile in Fig. 28.]

f [This was the little auxiliary signalling apparatus at the side of the
box, placed there for the same reasons as the auxiliary call-bell attached
to modern telephones.]

INVENTOR OF THE TELEPHONE. 83

84 PH1LIPP REI8,

here it goes through the conductor to the other station B and
from there returns to the battery.

" The apparatus B, a sonorous box on the cover of which
is placed the wire-spiral with the steel axis, wich will be
magnetic when the current goes through the spiral. A second
little box is fixed on the first one, and laid down on the steel
axis to increase the intensity of the reproduced sounds. On
the small side of the lower box you will find the correspondent
part of the complementary telegraph.

" If a person sing at the station A, in the tube (x) the
vibrations of air will pass into the box and move the membrane
above ; thereby the platina foot (c) of the movable angle will
be lifted up and will thus open the stream at every con-
densation of air in the box. The stream will be re-established
at every rarefaction. For this manner the steel axis at
station B will be magnetic once for every full vibration ; and
as magnetism never enters nor leaves a metal without dis-
turbing the equilibrium of the atoms, the steel-axis at station
B must repeat the vibrations at station A and thus reproduce
the sounds which caused them.

" Any * sound will be reproduced, if strong enough to- .set
the membrane in motion.

" The little telegraph, which you will find on the side of
the apparatus is very usefull and agreable for to give signals
between both of the correspondents. At every opening of the
stream and next following shutting the station A will hear a
little clap produced by the attraction of the steel spring.
Another little clap will be heard at station (B) in the wire-
spiral. By multiplying the claps and producing them in
different measures you will be able as well as I am to get
understood by your correspondent.

"I am to end, Sir, and I hope, that what I said will be

* [This word is underscored in Reis's original letter.]

INVENTOR OF THE TELEPHONE. 85

sufficient to have a first try ; afterward you will get on quite

alone.

" I am, Sir,

" Your most obediant Servant,

" PH. EEIS.
" Friedrichsdorf, 13/7, 63."

[9.] REIS'S PROSPECTUS.

[The following " Prospectus " of instructions was drawn up
by Reis to accompany the Telephones which were sold by
Herr Wilh. Albert of Frankfort. The author of this book is
in possession of original copies, of which a number are extant.
The " Prospectus " was also reprinted in its entirety at
page 241 of Professor Pisko's book ' Die neueren Apparate
der Akustik/ published at Vienna in 1865.]

TELEPHOK

Each apparatus consists, as is seen from the above illustra-
tion, of two parts : the Telephone proper, A, and the Repro-
duction apparatus [Receiver], C. These two parts are placed
at such a distance from each other, that singing, or the tones
of a musical instrument, can be heard from one station to the
other in no way except through the apparatus itself.

Both parts are connected with each other, and with the
battery, B, like ordinary telegraphs. The battery must be
capable of effecting the attraction of the armature of the
electromagnet placed at the side of station A (3-4 six-inch
Bunsen's elements suffice for several hundred feet distance).

The galvanic current goes then from B to the screw, d,
thence through the copper strip to the little platinum plate
at the middle of the membrane, then through the foot, c, of
the angular piece to the screw, &, in ivlwse little concavity a

PHILIPP REI8,

drop of quicksilver is put. From here the current then goes
through the little telegraph apparatus, e-f, then to the key
of station C, and through the spiral past i back to B.

If now sufficiently strong tones are produced before the
sound-aperture, S, the membrane and the angle-shaped little
hammer lying upon it are set in motion by the vibrations ;
the circuit will be once opened and again closed for each
full vibration, and thereby there will be produced in the iron
wire of the spiral at station C the same number of vibrations

Fig. 29.

which there are perceived as a tone or combination of tones
(chord). By imposing the little upper case (Oberkastchen)
firmly upon the axis of the spiral the tones at C are greatly
strengthened.

Besides the human voice (according to my experience)
there also can be reproduced the tones of good organ-pipes
from F — c and those of a piano. For the latter purpose A
is placed upon the sounding-board of the piano. (Of thirteen

INVENTOR OF THE TELEPHONE. 87

triads (Dreiklange) a skilled experimentor could with all
exactness recognise ten).

As regards the telegraph apparatus placed at the side, it
is clearly unnecessary for the reproduction of tones, but it
forms a very agreeable addition for convenient experimenting.
By means of the same, it is possible to make oneself
understood right well and certainly by the other party. This
takes place somewhat in the following manner: After the
apparatus has been completely arranged, one convinces one-
self of the completeness of the connexion and the strength
of the battery by opening and closing the circuit, whereby
at A the stroke of the armature is heard, and at C a very
distinct ticking.

By rapid alternate opening and closing at A it is asked at
C whether one is ready for experimenting, whereupon C
answers in the same manner.

Simple signals can by agreement be given from both
stations by opening and closing the circuit one, two, three,
or four times ; for example : —

1 beat = Sing.

2 beats = Speak, &c.

I telegraph the words thus — that I number the letters of
the alphabet and then transmit their numbers —

1 beat = a.

2 beats = 6.

3 „ = c.

4 „ = d.

5 „ = et &c.

z would accordingly be designated by twenty-five beats.

This number of beats would, however, appear wasteful of
time, and would be uncertain in counting, wherefore I employ

88 PHILIPP EEIS,

for every five beats a dactyl-beat (Dactylusschlag), and there
results — ^ ^ for e..

— ^ >^ and one beat for/, &c.

2, = — — - ^, — ^ ^^, — — — -, — *— ' — ', — •— - — -,
which is more quickly and easily executed and easier to
understand.

It is still better if the letters are represented by numbers
which are in inverse proportion to the frequency of their

occurrence.

PHIL. EEIS,

Teacher at L. F. Garnier's Institute for boys.
Friedrichsdorf, near Homburg-by-the-Height,
August 1863.

[The foregoing " Prospectus " was accompanied by a further
document printed as a postscript by Keis, at the top of which
the figure of the instrument was repeated, and which ran as
follows : — ]

"P.P.,

" Since two years ago I succeeded in effecting the
possibility of the reproduction of tones by the galvanic
current, and in setting up a convenient apparatus therefor,
the circumstance has found such a recognition from the most
celebrated men of science, and so many calls to action have
come to me, that I have since striven to improve my originally
very incomplete apparatus, so that the experiments might
thereby become accessible to others.

" I am now in the position to offer an apparatus which
fulfils my expectations, and with which each physicist may
succeed in repeating the interesting experiments concerning
reproduction of tones at distant stations.

" I believe I shall fulfil the wish of many if I undertake to
bring these improved instruments into the possession of the

INVENTOR OF THE TELEPHONE. 89

[physical] cabinets. Since the preparation of the same
requires a complete acquaintance with the leading principles
and a tolerable experience in this matter, I have decided
myself to prepare the most important parts of the same, and
to leave the fashioning of the accessory parts, as also of the
external adornments, to the mechanician.

" The distribution of the same I have made over to Herr
J. Wilh. Albert, mechanician, in Frankfort-on-the-Main, and
have placed him in the position to deliver these instruments
in two qualities, differing only in external adornment, at the
prices of 21 florins and 14 florins (12 thalers and 8 thalers
current), inclusive of packing. Moreover, the instruments
can also be obtained direct from me at the same prices, upon
a cash remittance of the amount.

" Each apparatus will be tested by me before sending off,
and will then be furnished with my name, an order-number,
and with the year of manufacture.

" Friedrichsdorf, near Homburg-by-the-Height,
" in August 1863.

" PHIL. EEIS,
" Teacher at L. F. Garnier's Institute for Boys."

[In September of the same year the telephone was shown
by Prof. K. Bottger at the meeting of the German Naturalists'
Association (Naturforscher), which met on that occasion at
Stettin. Little or nothing is known of what took place at
this exhibition, but Professor von Feilitzsch, of the neighbour-
ing University of Greifswald, has informed the author of
this work that the Telephone there shown was of the form
figured in Eeis's Prospectus (p. 86), and that Eeis claimed at
that time to be able to transmit words by his instruments.
In the same autumn the following notice appeared in
Bottger' s ' Notizblatt,' and was copied thence into Dingler's
' Journal/ and other scientific papers.]

90 PHILIPP EEIS,

[10,] ON THE IMPROVED TELEPHONE.

[Translated from the original notice which appeared in Bottger's ' Poly-
technisches Notizblatt,' 1863, Ko. 15, p. 225, and in Dingler's ' Poly-
technisches Journal,' 1863, vol. clxix. p. 399.]

At the meeting of the Physical Society of Frankfort-on-
the-Main, on the 4th of July, a member of this Society, Herr
Ph. Eeis, of Friedrichsdorf, near Homburg-vor-der-Hohe,
exhibited some of his improved Telephones (means for the
reproduction of tones at any desired distance by the galvanic
current). It is now two years since Herr Eeis first gave
publicity to his apparatus,* and though even already at that
time the performances of the same in their simple artless
form were capable of exciting astonishment, yet they had
then the great defect that experimenting with them was only
possible to the inventor himself. The instruments exhibited
in the above-named meeting scarcely reminded one of the
earlier ones. Herr Eeis has also striven to give them a
form pleasing to the eye, so that they may now occupy a
worthy place in every Physical Cabinet. These new apparatus
may now also be handled by every one with facility, jand
work with great certainty. Melodies gently sung at a
distance of about 300 feet were repeated by the instrument
which was set up, much more distinctly than previously.
The scale was reproduced especially sharply. The experi-
menters could even communicate words to one another,
though certainly indeed only such as had often been heard
by them. In order moreover that others who are less
accustomed [to experimenting] may be able to understand
one another through the apparatus, the inventor has placed
on the side of the same a little arrangement,! which accord-

* [Compare Bottger Polyt. Notizbl. 1863, p. 81, the notice translated
at p. 61 preceding.]— S. P. T.

f [This rather obscure passage refers to the call-key or communicator
fixed to the side of the instruments, and which as the inventor explains in

INVENTOR OF THE TELEPHONE. 91

ing to his explanation is completely sufficient, the speed of
communication of which is indeed not so great as that of
modern Telegraphs, but which works quite certainly, and
requires no special skill on the part of the one experimenting
with it.

We would bring to the notice of gentlemen who are
professional physicists that the inventor of these interesting
pieces of apparatus now has them prepared for sale under
his oversight (the important parts he makes himself), and
the same can be procured from him direct, or through the
mechanician, Mr. Wilhelm Albert, of Frankfort-on-the-Main,
at 14 and at 21 florins, in two qualities, differing only in
external adornment.

[A review, written by Dr. Rober of Berlin, of this and
other articles relating to the Telephone appeared subsequently
in the ' Fortschritte der Physik,' 1863, p. 96.]

[Another consequence of the publicity thus given to the
Telephone was the appearance of an article on that instru-
ment, under the title of " Der Musiktelegraph," in a popular
illustrated weekly family paper, ' Die Gartenlaube,' published
at Leipzig. This article, from the pen, it is believed, of Dr.
Oppel of Frankfort, is made up chiefly of slightly altered
extracts from the previously quoted documents. The form
of the instrument described is identical with that described
in Reis's ' Prospectus,' and the figure given in the ' Garten-
laube/ No. 51, p. 809, is a reprint, apparently from the same
wood-block of the figure which heads Reis's Prospectus, and
which is reproduced on p. 86 of this work. The only
passage of further interest is a brief sentence relating to the

his Prospectus (see p. 87), to be intended, like the call-bell or communicator
of modern telephones, as a means of sending signals to the speaker, and
which, as the Prospectus says, can also be used — as any call-bell can — for
telegraphing words by a pre-arranged code of signals.] — S. P. T.

92 PHILIPP SETS,

exhibition of the Telephone at the German Naturalists'
Assembly at Stettin in 1863, and is as follows : — ]

[11.] " Now in order also to give to a still wider circle,
especially to technologists (Fachmannern), the opportunity
of witnessing with their own eyesight th^ efficiency of this
apparatus, — lately, in fact essentially improved, — Professor
Bottger of Frankfort-on-the-Main exhibited several experi-
ments therewith at the meeting of the German Naturalists
(Naturforscher) and Physicians recently held at Stettin, in
the Section for Physics ; which [experiments] would certainly
have been crowned with still greater success if the place of
meeting had been in a less noisy neighbourhood, and had
been filled with a somewhat less numerous audience."

[The next extract is a brief record from the Eeport of a
scientific society meeting in Giessen, which during the
Austro-Prussian war of 1866 had become disorganised, and
which in 1867 published a condensed account of its proceed-
ings for the preceding years. Amongst those proceedings
was a lecture by the late Professor Buff, at which Eeis's
Telephone was shown, and at which Keis himself is believed
to have been present.]

[12.] [EXTRACT FROM THE ' TWELFTH KEPORT OF THE UPPER-
HESSIAN ASSOCIATION FOR NATURAL AND MEDICAL SCIENCE,'
(' Oberhessische Gesellschaft fur Natur und Heilkunde,')
Giessen, February 1867.]

P. 155. Eeport on the doings and condition of the Associa-
tion from the 1st of July, 1863, to the 1st of July, 1865, by
Herr Gymnasiallehrer Dr. W. Diehl.

... On the 13th of February [1864], ' On the Tones of
the Magnet, with Application to the Telephone, with experi-
ments,' by Professor Buff.

INVENTOR OF THE TELEPHONE. 93

EXHIBITION OF THE TELEPHONE TO THE NATURALISTS' ASSO-
CIATION OF GERMANY. (DEUTSCHE NATURFORSCHER VER-
SAMMLUNG.)

[By far the most important of all the public exhibitions
given by Eeis of his Telephone, was that which took place on
the 21st of September, 1864, at Giessen, on the occasion
of the meeting of the German Naturalists' Association
(Versammlung Deutsche Naturforscher). Here were as-
sembled all the leading scientific men of Germany, including
the following distinguished names, many of whom are still
living : — Prof. Buff (Giessen), Prof. Poggendorff (Berlin),
Prof. Bohn (Frankfurt-a.-M., now of Aschaffenburg), Prof.
Jolly (Munich), Dr. Geissler (Bonn), Prof. Weber (Gottingen),
Prof. Pllicker (Bonn), Prof. Quincke (Heidelberg), Prof.
Dellmann (Kreutznach), Prof. Bottger (Frankfurt-a.-M. and
Mainz), Prof. Kekule (Bonn), Prof. Gerlach (Erlangen),
Dr. J. Frick (Carlsruhe), Dr. F. Kohlrausch (Wlirtzburg),
Prof. Eeusch (Tubingen), Prof. J. Mliller (Freiburg), Prof.
Helmholtz (Heidelberg), Prof. Melde (Marburg), Prof. Kopp
(Marburg), Prof. A. W. Hoffmann (London, now of Berlin),
Mons. Hofmann (Paris, optician), Hofrath Dr. Stein (Frank-
furt-a.-M.), Dr. W. Steeg (Homburg), Mons. Hartnack (Paris,
and of Pottsdam), Prof. G. Wiedemann (Basel, now of Leipzig),
E. Albert (Frankfurt-a.-M., mechanician), Dr. Thudichum
(London), W. Schultze (York, apothecary), Dr. J. Barnard
Davis (Shelton), E. J. Chapman (London, chemist), Dr. L.
Beck (London, chemist), Prof. Chas. J. Himes (U.S.A.,
chemist), E. W. Blake (New Haven, U.S.A., student), C. G.
Wheeler (United States Consul in Niirnberg), and many
others. Dr. C. Bohn (now of Aschaffenburg) was Secretary
of the Association, and also Secretary of the Section of
Physics. The meetings of this Section were held in the
Laboratory of Professor Buff. Eeis came over from Fried-

94 PHILIPP REIS,

richsdorf accompanied by his young brother-in-law, Philipp
Schmidt. A preliminary trial on the morning of that day
was not very successful, but at the afternoon sitting, when
communications were made to the Section by Prof. Buff, by
Eeis himself, and by Prof. Poggendorff, the instrument was
shown in action with great success. Eeis expounded the
story how he came to think of combining with the electric
current interrupter a tympanum in imitation of that of the
human ear, narrating his researches in an unassuming
manner that won his audience completely to him ; and the
performance of the instrument was received with great
applause. Various professors essayed to experiment with
the instrument, with varying degrees of success according to
whether their voices suited the instrument or not. Amongst
these were Prof. Bottger and Prof. Quincke of Heidelberg,
whose account of the occasion is to be found on p. 112. Dr.
Bohn, the Secretary of the Section, wrote for the ' Journal '
(Tagesblatt), issued daily, the following notice.]

[13.] EXTRACT FROM THE EEPORT OF THE GERMAN NATU-
RALISTS' SOCIETY, HELD AT GIESSEN (1864).

"Afternoon sitting on 21st September, 1864.

" Prof. Buff speaks about the tones of iron and steel rods
when magnetised, and exhibits the corresponding experiments.

" Dr. Eeis demonstrates his Telephone, gives thereupon an
explanation and the history of this instrument.

" Prof. Poggendorff produces tones in a metal cylinder,
the slit up edges of which touch one another firmly, and
which is placed loosely round an induction-bobbin through
which there goes an interrupted current."

[This occasion was the crowning point of Philipp Eeis's
career, and might have proved of even greater importance
but for two causes : the inventor's precarious health, and the
indifference with which the commercial world of Germany
viewed this great invention. Where the keen insight of Eeis

INVENTOR OF THE TELEPHONE. 95

contemplated the vast possibilities opened out by the invention
of a new mode of inter-communication, others saw only an
ingenious philosophical toy, or at best a pleasing illustration
of certain known principles of acoustic and electric science.
And in spite of the momentary enthusiasm which the
exhibition of the Telephone had evoked, the interest in it
dwindled away. A few of the public journals of that date,
noticed the invention in eulogistic terms and spoke of the
prospect it afforded of communication between distant friends
and of simultaneous concerts being given in different towns,
all transmitted telephonically from one orchestra. But the
invention came too early. The public mind was not yet
prepared to take it up, and the enthusiasm died away. Still
in a few of the more important books on Physics, Acoustics,
and Electricity, the matter continued to receive attention. In
the well-known Muller-Pouillet's ' Textbook of Physics '
(Lehrbuch der Physik) edited by Professor J. Mliller ; in the
' Technical Physics ' of Hessler, of Vienna, edited by Pro-
fessor Pisko ; in Pisko's ' Eecent Apparatus of Acoustics,'
and particularly in Kuhn's admirable ' Handbook of Applied
Electricity,' the Telephone was accepted as a definite conquest
of science, and was described and figured. From the works
named we transcribe the extracts which follow, and which
sufficiently explain themselves.]

[14.] EXTRACT FROM MULLER-POUILLET'S ' TEXTBOOK OF
PHYSICS AND METEOROLOGY' (LEHRBUCH DER PHYSIK
UND METEOROLOGIE).

[Published at Brunswick, Sixth ed., 1863, vol. ii. page 352,
fig. 325; and Seventh ed., 1868, vol. ii. pages 386-388,
figs. 348-350. The following translation is from the latter
edition.]

" This tone. . . . has Reis used for the construction of his
Telephone.

96 PEILIPP REIS,

" Figure 348 * exhibits Eeis's interrupting apparatus. In
the lid of a hollow cube of wood A, a circular opening is made,
which is closed by an elastic membrane (pig's lesser intestine)
strained over it. Upon the centre of this membrane is glued
a little plate of platinum, which stands in conductive com-
munication with the clamping-screw a by means of a quite
thin little strip of metal / (distinctly visible in Fig. 349)
[Fig. 31].

" Upon the middle of the little platinum plate, rests a short
little platinum pencil, which is fastened at g to the under-
side of the strip of tin-plate h g i, one end of which, h, rests
upon the little metal pillar I, while a little platinum spike
fastened upon its under-side at it dips into the hollow of the
little metal pillar k, containing some quicksilver. The clamp-
ing-screw b, is put into conductive communication with the
little metal pillar k.

" From one pole of the battery there goes a conducting-
wire to the clamping-screw a of the interrupting apparatus
Fig. 348 [Fig. 30], from the other pole of the same there
goes a wire to the clamping-screw d of the reproducing
apparatus, Fig. 350 [Fig. 32], which is to be presently
described. The clamping- screw c, of this apparatus, is con-
nected by a wire with &, Fig. 348 [Fig. 30]. The clamping-
screws c and d are connected with the ends of the wire of the
small magnetising spiral M, Fig. 350 [Fig. 32] ; with the con-
nexion described above, the current of the current-generator
(battery) goes, therefore, through the spiral M.

" As soon now as the- sound-waves of an adequately
powerful tone enter through the mouth-piece S into the
hollow cube A, the elastic membrane which closes this at the
top is set into vibrations. Each wave of condensation on
entering lifts the little platinum plate together with the
little spike which sits upon it ; but if the membrane swings

* [Fig. 30 of this book.]

INVENTOR OF THE TELEPHONE.

downwards, the tin-piece Ji g i, with the little spike at i,
cannot follow it quick enough ; there therefore occurs here,
at each vibration of the membrane, an interruption of the

Fig. 30.

Fig. 31.

Fig. 32.

98 PHILIPP REIS,

current which lets itself be recognised by a little spark
appearing at the place of interruption.

" Now in the spiral M is stuck a knitting-needle, which, as
the figure shows, is fastened into a sounding-board. A lid
provided with second sounding-board may be clapped over
the spiral, and the tone be thereby greatly strengthened.

" If now, tones are produced before the mouth-piece S,
whilst one sings into the same or whilst one blows organ-
pipes, one at once hears at the reproducing apparatus a
peculiar creaking noise which is independent of the pitch of
the tones produced at the interrupting apparatus, but, beside
this, those tones are themselves reproduced ~by the steel wire dis-
tinctly perceptibly, and indeed Eeis found that this is the case
for all tones between F and /.

"In Keis's experiments the interrupting apparatus was
300 feet distant from the spiral, and was indeed set up in
another house with closed doors. But since the length of the
conducting wire can be extended just as far as in direct
telegraphy, Keis gave to his apparatus the name Telephone
(Jahresbericht des physikalischen Vereins zu Frankfurt-a.-M.
fur 1860/61)."

[15.] EXTRACT FROM PISKO'S ' DIE NEUEREN APPARATE DER

AKUSTIK.'

[This book, ' The more recent Apparatus of Acoustics/ by
Dr. Francis Joseph Pisko, Professor of Physics in the Gewer-
beschule in Vienna, was published at Vienna in 1865. At
that time the novelties in acoustics were Konig's apparatus
for the graphic study of sounds, Konig's manometric flames,
Schaffgotsch's singing flames, Helmholtz's ' Eesearches
on the Quality of Sounds,' Duhamel's Vibrograph, Scott
and Konig's Phonautograph, and Keis's Telephone. The
account given of the latter is more detailed in some respects
than any other published at the time.]

INVENTOR OF THE TELEPHONE.

Page 94. — PKINCIPLE OF THE " TELEPHON " OF EEIS.

51. (a) Allied to the Membrane Phonautograph is the
" Telephon" of Eeis* (Fig. 33). Upon the little membrane,
m m, in the middle, is fastened with adhesive wax the round
end s of a light strip of platinum, n s, so that the platinum
strip can join in with all the vibrations of the membrane.
Very near to the central end, s, of the little platinum strip,
n s, a platinum spike stands, in such a way that it is brought
into contact, by the vibrations of the membrane, with the
platinum strip that vibrates with the latter. Suppose now
that the outer end, n, of the platinum strip and the platinum
spike are connected with the poles of a galvanic battery, then,
by the vibration of the membrane the galvanic current will,
according to the phase of the vibration, be alternately esta-
blished and interrupted. Inserted in this circuit, an electro-
magnetic bell, or an electro-magnetic telegraph, will give
signals to great distances that somebody is speaking ; f though,
obviously, it cannot inform what is being spoken.

* [References."] Telephon von Eeis im Jahresbericljt des physikalischen
Vereins zu Frankfurt-a.-M. fur 1860-1861, pag. 57 bis 64. Muller-
Pouittet, Physik, 1863, 6. Auflage, II pag. 352, Fig. 325. Berl. Ber. fur
1861, xvii. pag. 171 bis 173. Der Musiktelegraph in der " Gartenlaube "
1863, Nr. 51, pag. 807 bis 909. Aus der Katur 1862, xxi. pag. 470 bis
484 ; Konig's Catalog, 1865, pag. 5.

f [This part of the apparatus is in fact a " call," serving precisely the
same function as the call-bell attached to ordinary telephones, by which
the subscriber can be "called up" to listen to the instrument. It is not
without importance to observe that this function was perfectly well-known
at the time ; fur it was gravely argued during a former telephone law-suit
in England that the presence of this " signal-call " at the side of the Reis
Transmitter was a proof that it was intended to transmit singing only
and not speech, or "else there would not have been that little Morse-
instrument at the side by which to talk " ! This suggestion is, however,
self-evidently absurd, because if this had been the case the little electro-
magnetic Morse telegraph would have been fixed, not on the side of the
transmitter but on that of the receiver. Reis himself explains the use of
the " call " (see p. 87) in his " Prospectus."]— S. P. T.

H 2

100

PHILIPP REIS,

(5.) As is known, an iron wire around which flow rapidly-
interrupted powerful galvanic currents, is thereby thrown
into tones which, according to circumstances, may be longi-

tudinal or transverse or both together. Such an iron wire,
lying in a multiplying wire-coil, Gf, Eeis inserted at the second
[receiving] station, C. The wire emitted sounds when the

INVENTOR OF THE TELEPHONE. 101

membrane was set into vibrations by singing or speaking
(at S, Fig. 33) into the hollow cubical piece A. In the inves-
tigations made by me with the telephone, the rod (of iron)
never altered the pitch of its tone with the most different
kinds of tones and clangs, and always gave only the rhythm
of the words sung or spoken into the piece A (the trans-
mitter) at S. Usually the air of the song that was sung could
be recognised by its rhythm.* The special researches on
these points follow in paragraph 53. However, it is so far
clear that there is still plenty of time yet before we have the
simultaneous concerts, and the transmission of singing to
different towns, as the daily newspapers have sanguinely
expected. The apparatus of Eeis is certainly a " Telephone "
but not a " Phonic Telegraph." The single means of trans-
mission for song and speech — and that only for moderate
distances — remains the old familiar speaking-tube. Never-
theless, the experiment of Eeis must ever be reckoned
amongst the most beautiful and interesting of school-experi-
ments. And since the means for this are so simple, the
apparatus of Eeis will certainly find a speedy entrance into
educational establishments that are only moderately endowed.
It is easily proved that the tones of the wire in the telephone
do not arise from acoustic conduction, for by cutting out the
coil from the circuit the tones immediately cease.

1. The Telephone of Keis originally consisted of a cube of
wood with a conical boring. The smaller opening was strained
over with a membrane. A knitting-needle which served for a
sounding wire projected about 2 inches on each side of the
multiplying coil, and lay upon the two bridges of a sounding-
box. The surrounding helix consisted of six layers of thin
wire. Fig. 33 shows the Telephone as it is constructed at the

* [Professor Pisko seems to have got hold of an unusually unfortunate
specimen of the instrument if he could make it neither speak nor sing.
His transmitter must have been in exceedingly bad condition to fail so
completely.]

102 PEILIPP REIS,

present time by the mechanician, Albert, in Frankfort, and by
the mechanician, Hauck, in Vienna, according to the directions
of the inventor.

[52.] Details about the Telephone.

(a.) The same (Fig. 33) consists in its essentials :

1. Of a transmitter, A ;

2. Of a receiver, C ;

3. Of a galvanic battery, B, and lastly,

4. Of the conducting wires that connect them.

(&.) The transmitter, A, is essentially a parallelepipedal
body of wood. The upper part, u x, of it is cut out of one
piece [of wood] with square cross -section, the side, xx, of
which measures 9 centimetres, and its height, ux,2'8 cen-
timetres.

This part is moveable upon a hinge on the lower little box,
A A. If the cover, x u, is laid back, one sees that a small
circle of 3' 9 centimetres diameter has been cut out in the
same. Into this hole passes a brass collar with a flange
8 millimetres broad, which is furnished at one side with a
groove like a pulley. Over the collar there is stretched the
membrane, ra m, by means of a silk thread lying in the
shoulder of the same. This circular membrane is surrounded
by a wider circular aperture, I ~b, = 8 • 5 centimetres. A shovel-
shaped little strip of platinum, n s, lies (over it) leading to
the brass binding-screw, d, with the circular part, s, falling
upon the centre of the membrane.

By means of some sealing-wax this circular part is fastened
to the membrane, and thereby compelled to take part in the
vibrations of the same. The further transmission of the
galvanic current from the centre takes place by means of a
platinum or steel point resting in a cup of mercury, which is

INVENTOR OF TEE TELEPHONE. 103

extended in a screw, which transmits the current farther.
The point a serves as a support for the angular hook, a s b,
which in general is supported like a tripod, in order that the
point of contact, s, may remain as constant as possible. The
hook, a s b, is simply struck with a hole at a upon a project-
ing point, and lies upon a broader under part. From b the
galvanic circuit proceeds by means of an overspun wire to the
brass key e (A, Fig. 33), and from there farther in the
direction represented by the arrow.

The lower part A A of the transmitter is put together of
thin wood and forms a parallelepiped, whose height = 6*8 cm.,
and whose width = 7'7 cm. An inclined mouthpiece of
tin with funnel-shaped opening serves to receive the tones.
The longer side of this mouthpiece measures 6 * 7 cm., the
shorter 4 • 7 cm. ; the longer diameter of the widening measures
7*15 cm., the shorter diameter 7*5 cm., and finally the
diameter of the narrow tube 3 • 9 cm.

It is clear that, if necessary, the platinum strip can be
replaced by a strip of thin sheet-brass, the platinum or steel
points by iron. Only in this case the points of contact must be
oftener cleaned to a metallic polish.

(c.) The receiver (Zeichengeber) C is in general a double
resonant box, whose upper part, " the cover," is moveable
upon two hinges, and can be laid back. The length of this
cover is 16*4 cm., its width 9*5 cm., and its height 3 '2 cm.
The length of the lower box measures 22-9 cm., its width
9 *6 cm., and its height 2*5 cm. The under part of the
resonant box bears two wooden bridges, which stand about
7 ' 4 cm. from each other, and which serves as supports for
the 21 • 5 cm. long, and 0 • 9 cm. thick iron needle destined for
reproducing the tones. The length of spiral wound over the
needle, and designed for making an electro-magnet of the
same, is 15 cm. The wooden covers of both parts, scraped

104 PEILIPP REIS,

as thin as possible, and the greatest breadth of the circular
holes shown in the figure, measures 13 mm.

(d.) For a battery one can successfully use a small Smee's
consisting of four elements, or two larger Bunsen's cells.

The conductor must be at least sufficiently long that one
cannot perceive the tones that are produced. For corre-
spondence between the two stations the inventor has employed
the electro-magnetic telegraph arrangement, e v g h, seen in
the mechanism, and easily understood. An agreement in
reference to corresponding signs can be easily arranged, and
the simplest way is to accept the signals arranged by the
inventor. (See ' Prospectus.')

The receiver C gives, when the key e is pressed, the cor-
responding telegraphic signals by means of tones in the rod
E E, while at the transmitter, A, the electro-magnet v gives
the signals by means of the springy armature z.

[53.] Experiments with the Telephone.

(a.) As soon as one brings the mouth to the funnel S and
sings, the membrane of the transmitter, A, vibrates in a
corresponding manner, and the iron rod, E E, at the second
station begins to give forth a tone. Every time a spark is
seen at the first station s, the rod ^at the other station
certainly gives forth a tone. The same is true when one
hears the peculiarly snarling tone which arises from the
stroke of the vibrating platinum strip against the spike of
angular hook resting upon it.

The appearance of these sparks or of the peculiar snarling
at the transmitter A gives the sign to the observers at the
station A that the rod in C is giving a tone. Tones and
melodies which were sung into the sound aperture, and
especially sounds in which the teeth and bones of the head
also vibrated (so-called humming tones), always evoked

INVENTOE OF THE TELEPHONE. 105

a tone in the rod or needle E E, and indeed, as already
mentioned (§ 51), without change in the pitch, but only
with the reproduction of the rhythm of the respective song
or words.

The pitch of the tone excited at C in the rod E E was in
the apparatus at my disposal h • its strength not very great
and its clang snarly, similar to that of a lightly sounding
reed- whistle, somewhat like that of a child's wooden trumpet.
The cuticle lying about the heart of the smaller and even the
larger mammals (from calves, &c.) makes the best membranes.
Goldbeater's-skins reproduce only the deeper tones. The
cover of the sounding-box appeared in my apparatus
superfluous, and indeed the tone was somewhat stronger
without the cover.

1. In experiments with the telephone, one must look closely
as to whether the ends of the platinum strip is still fastened to
the membrane, and one must, if necessary, press upon the
membrane. If the strip will no longer stick, heat a knife-blade,
touch a small piece of sealing wax with it, and carry thus
the melted sealing-wax to the under side of the round end
of the platinum-strip, n s. Then press it immediately on the
membrane, m m.

Ph. Eeis showed his apparatus in very primitive form for the first
time in October, 1861, to the Physical Society at Frankfort-on-the-Main ;
on July 4th, 1863, before the same society, he showed the form represented
in Fig. 33. This time he experimented upon a distance of 300 feet. Pro-
fessor Boettger brought the apparatus before the Naturforscher-Versamm-
lung at Stettin (1863) in the section for Physics.

*****

[16.] HESSLER'S ' TEXT-BOOK OF TECHNICAL PHYSICS/
vol. i. p. 648.

[Next in chronological order comes a notice of the
Telephone in Hessler's ' Lehrbuch der technischen Physik,'
edited by Prof. Pisko, and published at Vienna in 1866. The
brief account given in this work adds nothing to the accounts
previously given, and is evidently written by some person

106 PHILIPP REIS,

ignorant of Eeis's own work, for beside omitting all mention
of the transmission of speech by the instrument, or of its
being constructed upon the model of the human ear, the
writer appears not even to know how to spell Keis's name,*
and speaks of him as " Eeuss."]

[17.] KUHN'S 'HANDBOOK OF APPLIED ELECTRICITY,'

(' Handbuch der Angewandten Elektricitatslehre,' von Carl
Kuhn), being vol. xx. of Karsten's ' Universal Encyclopaedia of
Physics ' (Karsten's ' Allgemeine Encyclopadie der Physik ').

[Karsten's ' Encyclopaedia of Physics,' which has been for
many years a standard work of reference, both in Germany
and in this country, consists of a number of volumes, each of
which is a complete treatise, written by the very highest
authorities in Germany. Thus Helmholtz contributed the
volume on Physiological Optics, Lamont that on Terrestrial
Magnetism, whilst the names of Dr. Brix, Professor von
Feilitzsch, and others, are included amongst the authors.
Carl Kuhn, who wrote vol. xx., was Professor in the Eoyal
Lyceum of Munich, and member of the Munich Academy.
Kuhn's volume on ' Applied Electricity,' published in 1866,

* This error has been copied by Count du Moncel, along with the other
defects of the article, into the fifth volume of his * Applications of Elec-
tricity,' published in 1878. It is rather amusing now to read, at p. 106,
of Du Moncel's treatise that " Heisler " (sic) " pretends " that the telephone
of " Eeuss," which " appears " to have been invented " anterior to the year
1866," was capable of transmitting vocal melodies ! Count du Moncel,
though he has since posed as an authority on the telephone, did not in
1878 shine in that capacity, for on the very same page of the Count's book
may be found the following astounding sentiment : — " Jf it is true, as Sir
W. Thomson has assured us, that at the Philadelphia Exhibition of 1876
there was a telegraphic system transmitting words, we may recognize," &c.
Count du Moncel has since found out that it is true that there was a
Telephone in Philadelphia in 1876 : perhaps he will next discover that
" Reuss" did, "anterior to the year 1866," actually "appear" to transmit
not only what "Heisler" "pretends" he did, but that he also transmitted
spoken words. — S. P. T.

INVENTOE OF THE TELEPHONE. 107

is to be found on the shelves of almost every library of any
pretensions in Great Britain. The account given therein of
Eeis's Telephone is interesting, because it describes two
forms, both of transmitter and of receiver. In fact the
descriptions and figures are taken almost directly from von
Legat's Eeport (p. 70), and from Eeis's Prospectus (p. 87).
The extract translated below includes all the matter that is
of importance.]

P. 1017. The researches established by Eeis on the 26th
of October, 1861, in Frankfurt* have already shown that
if the current interruptions follow one another almost con-
tinuously and very rapidly, in a spiral arranged with a thin
iron core, the iron wire can be set into longitudinal vibra-
tions, whereby therefore the same is constrained to reproduce
tones of different pitch.

* * # *

[Here follows a reference to Petrina's Electric Harmonica.]

* * * *

From the communications made known by Legat, it'
follows that " the ideas concerning the reproduction of tones
by means of electro-galvanism which were put forward some
time since by Philipp Eeis of Friedrichsdorf, before the
Physical Society, and the meeting of the Free German
Institute in Frankfort-on-the-Main," relate to similar arrange-
ments. " What has hitherto been attained in the realisation
of this project," Legat announces in his report, and we
extract therefrom only that part which gives an explanation
of the disposition of the telegraphic apparatus, with which it
is said to be possible to produce the vibrations and the
excitement of tones in any desired manner, and by which
the employment of electro-galvanism is said to make it

* Ueber Fortpflanzung der Tone auf wilkiihrlich weite Entfermmgen,
mit Hiilfe der Elektricitiit (Telephonic). Polyt. Journ. clxviii. 185 ; aus
Bottger's Notizbl. 1863, Nr. 6. "[See translation on page 61.]

108 PHILIPP REIS,

possible "to. call into life at any given distance vibrations
similar to the vibrations that have been produced, and in this
way to reproduce at any place the tones that have been
originated at another place."

This apparatus consists of the tone-indicator (transmetteur)
and the tone-receiver (recepteur). The tone-indicator
(Fig. 34, p. 1 09) consists of a conical tube, a b, having a
length of about 15 cm., a front aperture of about 10 cm.,
and a back aperture of about 4 cm., the choice of the
material and the greater length of which is said to be in-
different, while a greater width is said to be injurious ; the
surface of the inner wall should be as smooth as possible.
The narrow back aperture of the tube is closed by a
membrane, o, of collodion, and upon the centre of the circular
surface formed by this membrane rests the one end, c, of the
lever, c d, the supporting-point of which, et being held by
a support, remains in connection with the metallic circuit.
This lever, the arm, c ey of which must be considerably
longer than c d, should be as light as possible, so that it
can easily follow the movements of the membrane, because
an uncertain following of the lever, c d, will produce
impure tones at the receiving station. During the state of
rest the contact, d g, is closed, and a weak spring, n, keeps
the lever in this state of rest. Upon the metallic support, /,
which is in connection with one pole of the battery, there is
a spring, g, with a contact corresponding to the contact of the
lever, c d, at d, the position of which is regulated by means of
the screw, h. In order that the effect of the apparatus may
not be weakened by the produced waves of air communicat-
ing themselves towards the back part, a disc " of about
50 (?) cm. diameter, which rests fixedly upon the exterior
wall of the tube," is to be placed above the tube, a b, at right
angles with its longitudinal axis.

The tone-receiver consists of an electro-magnet, m m, which

INVENTOR OF THE TELEPHONE.

109

110 PHILIPP REIS,

rests upon a resounding-board, u w, and the surrounding coils
of which are connected with the metallic circuit and the
earth. Opposite to the electro-magnet there stands an
armature, which is connected with a lever, i, as long as
possible but light and broad, and which lever together with
the armature, is fastened like a pendulum to the support k ;
its movements are regulated by the screw I and the spring q.
" In order to increase the effect of the apparatus, this tone-
receiver may be placed in the one focus of an elliptically
hollowed cavity of sufficient size, while the ear of the person
who listens to the reproduced sounds ought to be placed at
the second focus of the cavity." The action of the two
apparatus, the general manner of connection of which may be
seen from the illustrations — at the one station being the
tone-indicator, at the other the tone-receiver — is the follow-
ing : — By speaking into, singing, or conducting the tones of
an instrument into the tube, a I, there is produced in the
tone-indicator (Fig. 34) in consequence of the condensation
and rarefaction of the enclosed column of air, a motion of the
membrane, c, corresponding to these changes. The lever, c d,
follows the movements of the membrane, and opens or closes
the circuit according as there occurs a condensation or rare-
faction of the enclosed air. In consequence of these actions,
the electro-magnet, m m (Fig. 13), is correspondingly demag-
netised or magnetised, and the armature (and the armature-
lever) belonging to it is set into vibrations similar to
those of the membrane of the transmitting apparatus. By
means of the lever, i, connected with the armature, the
similar vibrations are transmitted to the surrounding air,
and these sounds thus produced finally reach the ear of the
listener (the sounding-board increasing the effect). As
regards the effectiveness of this apparatus, the author
remarks that while the similar number of the produced
vibrations is reproduced by the receiver, their original

INVENTOR OF THE TELEPHONE. Ill

strength has not yet been obtained by it. For this reason
also small differences of vibration are difficult to hear, and
during the practical experiments hitherto made, chords,
melodies, &c., could be, it is true, transmitted with asto-
nishing (?) fidelity, while single words in reading, speaking,

&c., were less distinctly perceived.

* * * *

[The rest of the article deals with the "square-box" transmitter
described in Eeis's Prospectus, and adds nothing to the information already
published.]

[This is the last of the contemporary documents bearing
upon the performance of Eeis's instruments. From the
prominent notice obtained at the time by the inventor, it is
clear that his invention was even then accorded an honour-
able place amongst the acknowledged conquests of science.
A critical examination of this body of evidence proves not
only the substantial nature of Eeis's claim, but that the
claim was openly recognised and allowed by the best autho-
rities of the time. The thing was not done in a corner.]

112 PHILIPP BEIS,

CHAPTEE V.

TESTIMONY OF CONTEMPORARY WITNESSES.

1. Professor G. Quincke.

2. Professor C. Bohn.

3. Herr Leon Gamier.

4. Ernest Horkheimer, Esq.

5. Dr. K. Messel, F.C.S.

6. Herr Heinrich Holt.

7. Herr Heinrich F. Peter.

8. Mr. Stephen M. Yeates.

9. Dr. William Frazer.

PROFESSOR G. QUINCKE,

Professor of Physics in the University of Heidelberg.

[Professor Quincke, whose name is so well known in connection with
his researches in molecular physics and in many problems of the highest
interest to those acquainted with electrical science, was one of those
present at the Naturforscher Yersammlung held at Giessen in 1864, where
Reis's Telephone was publicly exhibited by its inventor, see page 93,
ante. His testimony, coming from so high authority, is therefore of
exceptional value.]

" DEAR SIR,

" I was present at the Assembly of the German Na-
turalists' Association (Naturforscher Versammlung) held in
the year 1864 in Giessen, when Mr. Philipp Eeis, at that
time teacher in the Gamier Institute at Friedrichsdorf, near
Frankfort-on-the-Main, showed and explained to the assembly
the Telephone which he had invented.

" I witnessed the performance of the instruments, and, with
the assistance of the late Professor Bottger, heard them for
myself.

" The apparatus used consisted of two parts — a transmitter

INVENTOR OF THE TELEPHONE. 113

and a receiver. The transmitter was a box, one side of which
was furnished with a tube into which the speaking was to
be done. At the top or the side of the box there was a cir-
cular opening, covered by a tympanum of membrane, upon
which was fastened a piece of platinum. This piece of
platinum was in communication with one pole of the galvanic
battery. Over the membrane, resting upon the platinum, and
in contact with it, was a piece of metal furnished with a
platinum point, also in connection with one pole of the
battery.

" The receiver consisted of a common knitting needle of
steel, surrounded by a magnetising coil of insulated wire, which
also formed a part of the circuit, the whole resting on a
resonant box.

" I listened at the latter part of the apparatus, and heard
distinctly both singing and talking. I distinctly remember
having heard the words of the German poem, ' Ach ! du lieber
Augustin, Alles ist hin ! '" &c.

" The members of the Association were astonished and
delighted, and heartily congratulated Mr. Eeis upon the
success of his researches in Telephony.

(Signed) " DR. G. QUINCKE, Professor.
" Heidelberg, 10th March, 1883."

PROFESSOR C. BOHN.

[Professor C. Bohn, of Aschaifenburg, was formerly Secretary to the
German " Naturforscher " Association, was also Secretary to the Physical
Section of this Society (vide p. 93). In that capacity he had every
opportunity of knowing what was going on in science ; hence the following
(translated) letter, addressed to the author of this book, is of peculiar
value.]

" MOST ESTEEMED SlR,

" I willingly answer, as well as I am able to do so, the
questions put by you. In order to explain that my recollec-

114 PHILIPP RE IS,

tions may not have all the sharpness that might be wished,
I make the following prefatory statement. I have, about
1863, held numerous conferences with Mr. Eeis and with my
deceased colleague, Professor H. Buff, of Giessen, and on
these occasions have argued the question how it is that the
transmission of thoughts to a distance by the sensation of
the ear has a distinctly less value than transmission by that
which is written. . . .

" And now to your questions. I was not at Stettin in 1863.
At the experiments at Giessen in the Naturforscher Assembly
on 21st September, 1864, 1 was present ; the short notice about
them in the journal (' Tagesblatt ') is from my pen. I was
Secretary of the Assembly and of the Physical Section. I
remember, however, almost absolutely nothing about these
experiments. But I remember well that previously — therefore
probably as early as 1863 — having jointly made the experi-
ments with Eeis's telephone in Buff's house in Giessen. . . .
I have myself, as speaker and as hearer, at least twice, in the
presence of Eeis, made the experiments.

" It was known to me (in 1863-64) that Eeis intended to
transmit words, and certainly spoken words as well as* those
sung. My interest in the matter was, however, a purely
scientific one, not directed to the application as a means of
profit.

"With great attention the sense of the words was understood.
I have understood such myself, without knowing previously
what would be the nature of the communication through the
telephone. Words sung, especially well accentuated and
peculiarly intoned, were somewhat better (or rather less
incompletely) understood than those spoken in the ordinary
manner. There was indeed a boy (son of Privy-Councillor
Ihering, now of Gottingen, then of Giessen), who was known
as specially accomplished as a speaker. He had a rather
harsh North-German dialect, and after the first experiments

INVENTOR OF THE TELEPHONE. 115

hit on the right way to speak best, essential for understand-
ing. I myself did not understand Professor Buff through the
telephone. Whether the speaker could be recognized by his
voice I doubt. We knew beforehand each time who speaks.
Yet I remember that a girl could be distinguished from
that boy by the voice.

" The ear was at times laid upon the box of the apparatus,
also upon the table which supported the telephone. Then it
was attempted to hear at a distance, with the ear in the air ; in
this respect, when singing, with good result. At times the
lid was taken off, or the same was connected more or less
tightly or loosely with the lower part. The result of these
changes I can no longer give with distinctness. . . .

" Should you desire further information, I am ready to give
you it according to my best knowledge.

" Hochachtungsvoll ergebenster,

"DR. C. BOHN.

" Aschaffenburg,

" Wth September, 1882."

LEON GARNIER.

[Herr Leon Gamier, Proprietor and Principal of the Gamier Institute at
Friedrichsdorf, is the son of the late Burgomaster Gamier, who founded
the establishment, and who, as previously narrated, encouraged Philipp
Reis in his work and offered him the post of teacher of Natural Science.
Herr Leon Gamier owns the small collection of instruments which Reis
left behind, and which are preserved in the Physical Cabinet attached to
the Institute, where also may be seen the gravitation machine — an
ingenious combination of the principles of Atwood's and Morin's machines
— and the automatic weather-recorder invented by Reis, both, however,
very greatly out of repair. Herr Garnier has furnished to a friend the
following particulars about Reis and his invention.]

" I knew Philipp Beis, now deceased, during his life-time.
. . . About the year 1859, he was employed by my father,
then proprietor and director of the Friedrichsdorf Garnier
Institute, as teacher of mathematics and natural sciences.

i 2

116 PHILIPP EEIS,

He employed his hours of leisure in experimenting for
himself in a house occupied by himself, and in which he had
established a physical laboratory with a view mainly of
realizing an idea which he had conceived sometime before of
transmitting the human voice over divers metallic conductors
by means of a galvanic current. ... I remember especially,
that, standing at the end of the wire or conductor, Mr. Eeis
speaking through his instrument, I distinctly hea,rd the
words : ' Guten Morgen, Herr Fischer ' (Good morning,
Mr. Fischer) ; ' Ich komme gleich ' (I am coming directly) ;
Passe auf!' (Pay attention!); 'Wie viel Uhr ist es?'
(What o'clock is it?); <Wie heisst du?' (What's your
name?) We often spoke for an hour at a time. The
distance was about 150 feet.

" LEON GARNIER."

ERNEST HORKHEIMER, ESQ.

" Manchester, Dec. 2, 1882.
" Professor S. P. THOMPSON,

"DEAR SIR,

" In reply to your favour of 31st instant, I shall be
very happy to give you all the information I can with respect
to the telephonic experiments of my late friend and teacher
Mr. Philipp Keis. I would express my gratification at finding
that you are trying to put my old teacher's claims on their
just basis. I have always felt that in this race for telephonic
fame, his claims have been very coolly put aside or ignored.
That he did invent the Telephone there is not the remotest
doubt. I was, I think, a great favourite of his ; and at the
time his assumption was that I was destined for a scientific
career, either as a physicist or a chemist ; and I believe that
he said more to me about the telephone than to any one; and
I assisted him in most of his experiments prior to the spring
of 1862.

INVENTOR OF THE TELEPHONE.

117

" Philipp Eeis intended to transmit speech by his telephone
— this was his chief aim ; the transmitting of musical tones
being only an after-thought, worked out for the convenience
of public exhibition (which took place at the Physical Society
at Frankfort-on-the-Main). I myself spent considerable time
with him in transmitting words through the instruments.
We never (in my time) got the length of transmitting com-
plete sentences successfully, but certain words, such as ' Wer
da?' 'gewiss' 'warm,' 'halt' were undoubtedly transmitted
without previous arrangement. I believe Eeis made similar
experiments with his brother-in-law.

" I recollect the instrument in the shape of the human ear
very well : it was Eeis's earliest form of transmitter. The
transmitter underwent a great many changes, even during my
time. The form you sketch (Fig. 9, p. 20) was almost the
oldest one, and was soon superseded by the funnel-shape
(Fig. 35).

Fig. 35.

Fig. 36.

The back was always closed by a tympanum of bladder, and
many a hundred bladders were stretched, torn, and discarded
during his experiments. I recollect him stating to me that
he thought a very thin metal tympanum would eventually
become the proper thing, and one was actually tried, coated
over on one side with shellac, and on the other likewise
except at the point of contact (Fig. 36). I believe it was
made of very thin brass, but at the time the experiments
were not satisfactory. Talc was also tried, but without
success, the platinum contacts being in all cases preserved.

118

PHILIPP REIS,

" I remember very well indeed the receiver with a steel
wire, surrounded by silk-covered copper wire. The first one
was placed on an empty cigar-box, arranged thus : —

Fig. 37.

" The wire was a knitting-needle and the copper wire was
spooled on a paper case, ft \

" The spiral was supported by a little block of wood, so as
to allow the knitting-needle not to touch it anywhere. Later
on a smaller cigar-box was invented as a cover — thus ; (Fig. 38)
— having two holes cut into it like the /-holes in a violin.

Fig. 38.

" The practice was to place the ear close to the receiver,
more particularly so when the transmission of words was
attempted.

" The spiral was, during the early experiments, placed on a
violin — in fact, a violin which I now possess was sometimes
used, as it was of a peculiar shape, which Eeis thought would
help the power of tone.

" I have already enumerated some of the words which were

INVENTOR OF THE TELEPHONE.

119

transmitted, but there were many more ; on one occasion a
song, known in this country as ' The Young Eecruit ' (Wer
will unter die Soldaten) was transmitted, the air and many
of the words being clearly intelligible.

" I do not recollect seeing the receiver shewn in the wood-
cut (Fig. 21), but Eeis often said that he would make such
a one, although the sketch he made for me then differed in
some details from your woodcut. Eeis intended to keep me
fully informed of all he could achieve, but, immediately after
leaving his tuition, I fell ill, and was laid up for a very long
time. Shortly afterwards I left for England, and then he
died, and I never saw him again. The electromagnet form
was certainly strongly in his mind at the time we parted,
and he drew many alternative suggestions on paper, which
have probably been destroyed; but the electromagnets in
all of them were placed upright, sometimes attached to the
top of a hollow box, and sometimes to the bottom of a box
arranged thus (Figs. 39, 40) ; but, to my recollection, they
never got beyond the stage of drawings, whatever he may
have done after he and I parted company.

Fig. 39.

V U

Fig. 40.

" In conclusion, I beg to send you herewith a photograph
of Philipp Eeis (see Fig. 12, p. 23), holding in his hand the
instrument I helped him to make, and which photograph he
took of himself, exposing the camera by a pneumatic arrange-
ment of his own, and which formed part of a little machine
which he concocted for turning over the leaves of music-books.

" The instrument used by Eeis at the Physical Society may

120 PHILIPP REIS,

have been the square block form : I believe that this cone-
form was not quite completed then. At the Saalbau (Hoch-
stift), however, I am sure the instrument shown in my photo-
graph was employed ; not with a tin cone, but a wooden one.
I send you herewith a sketch of what I remember that
instrument to have been. I am not absolutely certain
whether in the instrument there was not an electromagnet
introduced, but I think not. My recollection leads me to
suppose that the electromagnet arrangement was added sub-
sequently. Thinking it over again, I should, however, think
that the instrument in the photo must have been one in
which a bent lever was placed behind the tympanum, and
that the rectangular patch seen above was a wooden casing
to shelter the parts. There may be some confusion in my
mind as to the position of this box, but I somehow think
the rectangular patch is only part of a larger box which is
not apparent in the photograph. I have no idea where
the original instrument is now, but I should hardly think
it could be in existence. Eeis used to take some in-
struments to pieces to utilise parts in subsequent experi-
ments, and I recollect how keen he used to be about the
bits of platinum, which he always described as ' ein sehr
kostbares Metall.' What always was a great puzzle was the
attaching of the platinum plate to the membrane, which he
did generally by sealing-wax, saying at the same time : ' Es
ist nicht recht so, aber ich weiss nicht wie es anders gemacht
werden kann ! '

" Believe me, my dear Sir, yours truly,

" ERNEST HORKHEIMER."

DR. EUDOLPH MESSEL.

[The following letter from Dr. Rudolph Messel, F.C.S., addressed to the
author of this hook, in reply to enquiries concerning Ileis and his inven-
tions, speaks for itself. Dr. Messel's letter differs from almost all the

INVENTOR OF THE TELEPHONE. 121

others here reprinted in having been specially written for the purpose of
being inserted in this volume. — S. P. T.]

" 36, Mark Lane, London, 30ta April, 1883.

" DEAR PROFESSOR THOMPSON,

" At last I find a moment to comply with your request.
My knowledge of Philipp Keis dates from 1860, when I
was a pupil at Professor Garnier's School at Friedrichsdorf,
of which school Eeis was one of the undermasters. Eeis,
naturally communicative, was very fond of talking to us boys
about his scientific researches. And it was on the occasion
of one of our daily walks together that he told me how,
when an apprentice at Beyerbach's (colour-manufacturer), in
Frankfurt-a.-M., he was one day amusing himself in watching
the behaviour of a small magnetic compass. This compass
he found, on being placed near to the base of various iron
columns in the warehouse, was attracted. Disturbed by the
entrance of one of the principals, who imagined that Eeis
ought to employ his time more profitably, he withdrew to a
stage where he could pursue his experiments unobserved.
Much to his surprise, he now found that the pole attracted
by the base was repulsed at the top of the columns, which
observation led him to examine other pieces of iron on the
premises. He next built up a column with all the weights
in the warehouse, and having verified his previous observa-
tions, he communicated what he believed to be his first and
great discovery either to Professor Bottger or to Dr. Oppel.
Great was his diappointment to learn at this interview that
he had unwittingly stumbled across a well-known physical
fact : but his disappointment stimulated in him the desire to
learn more of the marvellous laws and mysteries of nature.
That Eeis evoked a similar desire in those with whom he
came in contact need not cause surprise, and thus it came
about that Horkheimer, Kuster, Schmidt, and myself, soon

122 PEILIPP REIS,

enjoyed the privilege of private instructions in physics, and
of being permitted to witness his telephonic experiments
amongst others. I was, however, very young, and am sorry
that much that I then saw and heard has been forgotten.
Keis insisted that his transmitter (which he called the
'ear') should be capable of performing the functions of
that organ, and he never tired of drawing diagrams of the
numerous curves of sounds to explain how necessary it was
that the transmitter should follow these curves before perfect
speaking could be attained, and which kind of curves the
instrument so far could reproduce. Numerous experiments
were made with transmitters, exaggerating or diminishing
the various component parts of the ear. Wooden and me-
tallic apparatus, rough and smooth, were constructed in order
to find out what was essential, and what was not.

"One form of transmitter was at that time constructed
which I miss amongst the various woodcuts you were good
enough to send me, and one which Eeis based great hopes
upon. The instrument was very rough, however, consisting
of a wooden bung of a beer-barrel (which I had hollowed out
for an earlier telephone — it was not turned inside* like
others), and this was closed with a membrane. The favourite
' Hammerchen ' was replaced by a straight wire, fixed in
the usual way with sealing-wax, and
the apparatus stood within a sort of
tripod, membrane downwards, the pin
just touching the surface of a drop of
mercury contained in a small cup form-
ing one of the terminals of the circuit.
The apparatus started off with splendid
results, but may probably have been abandoned on account of
its great uncertainty, thus sharing the fate of other of his
earlier instruments. In my belief it is to these mechanical
imperfections, due principally to the want of sufficient means

INVENTOR OF THE TELEPHONE. 123

at his command, that we must look to find the reason why
Eeis's telephone did not come to an earlier fame. Thus Eeis
informed me that he intended to exhibit it once at some
scientific meeting at Cassel, but notwithstanding a perfect
rehearsal it was impossible to show the working to the audi-
ence ; the failure was attributed by Eeis to atmospheric influ-
ence (stretching of the diaphragm), and he felt much grieved
at having lost his chance. To make matters worse, the early
transmitters had no adjusting screws, and the contact was only
regulated by a piece of bent wire, and the ' hammer ' was fixed
to the membrane. Philipp Schmidt should recollect what I
state, as many experiments were made when only he, Eeis, and
myself were present, he being at one and I at the other end
of the apparatus. The wire was stretched from Eeis's house,
in the main road, through the yard to a hayloft, near the
garden or field. We transmitted musical sounds (organ, &c.),
singing popular songs (' Wer will unter die Soldaten,' ' Ich
hatt' einen Kameraden,' &c.) and speaking, or, more cor-
rectly, reading. We had a book, and were to find out what
part of the page the reader was just transmitting. We fre-
quently used a sort of 'Exercier Eeglement,' a soldiers'
instruction book, or something of that sort. I have a
distinct recollection of electromagnetic receivers being used,
but not of their construction, except that the use of one of
them was accompanied by a rattling and disturbing noise.
The knitting-needle put in the / of a violin was, however,
the more favoured receiver, but at this time, in Eeis's mind,
all seemed to hinge on the electromagnet, as it had before,
and, I dare say, did again afterwards on the transmitter. I
left Friedrichsdorf in '62, and rarely saw Eeis after that,
except a few times at Mechanicus Albert's (who made some
of his apparatus), and at Professor Bottger's, to whom he
introduced me. Eeis attended Professor Bottger's lectures
at the Physikalischer Verein, when in Frankfort, prior to his

124 PHILIPP RE IS,

settling down at Friedrichsdorf ; but I do not know that
any particularly intimate relation existed between them.
Dr. Poppe, director of the Gewerbeschule (Trade School),
now deceased, on whose advice he chiefly relied, was then
one of his more intimate friends, Professor Oppel being
occasionally consulted about more intricate mathematical
problems. Of the 'meteorological recorder' invented by
Eeis I recollect but its existence, but nothing at all of a
1 fall-machine ' of his construction. The velocipede I only
recollect, because he lent it to me for a masquerade. At his
suggestion we altered it into a large musical-box, putting
Herr Peter inside, who played on the clarinet when I
turned a handle. Dr. Kellner states that its chief merit
consisted in being able to go downhill, and that poor Eeis
came back (uphill) puffing away, dragging his velocipede
behind him. Kellner no doubt could give valuable informa-
tion on Eeis's theory of electricity, his conviction that there
was only one kind of electricity, his acoustic researches, and
those on radiation of electricity, his galvanoplastic experi-
ments, &c., &c.

" In personal appearance Eeis was not very refined, but
he had a striking countenance and a very powerful look.
Though occasionally very irritable, especially with dunces,
he was always warm-hearted, and showed great kindness to
those who cared to understand him. Eeis's views of the
telephone may, of course, have changed after I knew him,
and looking at his later instruments, one of which I possess,
I cannot help thinking they did ; at any rate, I do not see
how, in these instruments, the current got interrupted at all,
and the instruments must have acted like microphones,
whether known or unknown to him. When listening to the
instrument he frequently said to me, " You understand it is
a ' molekular Bewegung ' (molecular motion).

" I am sorry that, owing to the lapse of time, I am unable

INVENTOR OF THE TELEPHONE. 125

to throw more light on Eeis's original labours in a field of
physical science which promised so much for the future ;
but insufficient as are my recollections, they may not be
without public interest, and at any rate I am glad of this
opportunity of offering my humble tribute of regard and
affection to the memory of my old teacher and friend.

" Yours truly,

"BuDOLPH MESSEL."

HEINRICH HOLD.

[Herr Hold, formerly a colleague of Philipp Keis in the Gamier Institute
at Friedrichsdorf, but EOW proprietor of a leather factory in the same
place, was teacher of mathematics. He was in his younger days a fellow-
student of Professor Tyndall at Halle, and was well acquainted with
physical science in general. His intimate connection with Eeis, and close
knowledge of Keis's work, enable him to confirm the testimony of others
in many important points.]

To Professor S. P. THOMPSON in Bristol.

" ESTEEMED SIR,

" I have much pleasure in furnishing you with the
following particulars concerning my late colleague Philipp
Eeis, the inventor of the Telephone. He was himself educated
at the Garnier's Institute in Friedrichsdorf where I was also
teacher of mathematics. I knew him very well during his
life-time. Among his numerous original researches, his
invention of the telephone was the principal one. His idea
was to reproduce the tones both of musical instruments and
of the human voice by means of electricity, using a covered
wire wound in a spiral round an iron core, the same being
placed upon a resonant box. In this he succeeded, inasmuch as
with an apparatus, which he showed to the Physikalischer
Verein in Frankfurt-a.-M., in the year 1861, he repro-
duced music, singing, single words and short sentences ; all
of which were distinctly audible over a short distance from

126 PEILIPP REIS,

his dwelling-house through the yard to the barn. Every
voice was not equally well adapted for speaking into the
apparatus, neither could every ear understand the telephone
language equally well. Words spoken slowly, and singing,
both in a middle tone, were the most easy to reproduce. I
helped Mr. Eeis to make many of his experiments, and have
spoken and sung into the telephone, the same being generally
heard and understood. I have also heard and understood
short sentences when I was standing at the end station. A
brother-in-law of Mr. Eeis, who is now paymaster in the
Imperial Navy at Wilhelmshavn, generally conducted the
speaking and singing in the telephone.

" HEINRICH HOLD."

HEINRICH FRIEDRICH PETER.

[Herr Peter is still Music-teacher in the Gamier Institute, and has a
vivid recollection of his former colleague Philipp Reis, and of the experi-
ments with the telephone.]

5< DEAR SIR,

"The following particulars concerning Reis's" Tele-
phone I have several times narrated. I was teacher of
music in Garnier's Institute at the time when Mr. Eeis
invented the telephone, in the year 1861. I was much
interested in his experiments, and visited him daily, giving
him help and making suggestions. His first idea was to
imitate the construction of the human ear. He constructed
a funnel-shaped instrument, the back of which was covered
with a skin of isinglass, upon which was fastened a piece of
platinum, against which rested a platinum point. As receiver
of the electric current he used a common knitting-needle,
surrounded by a coil of insulated green wire, which was at
first merely laid on a table. At first the tones were very
much interfered with by a buzzing noise. At my suggestion

INVENTOR OF THE TELEPHONE. 127

he placed the spiral upon my violin as a resonant-box;
whereupon the tones were perfectly understood, though
still accompanied by the buzzing noise. He continued
experimenting, trying various kinds of membranes, and
made continual improvements in the apparatus. I was
present and assisted at the experiments at Frankfort-on-
the-Main, on the 26th of October, 1861 ; and after the
meeting broke-up, I saw the members of the Society
as they came and congratulated Mr. Keis on the success
of his experiments. I played upon the English horn, and
Philipp Schmidt sang. The singing was heard much
better than the playing. At an experiment which we made
at Friedrichsdorf, in the presence of Hofrath Dr. Muller,
Apothecary Muller, and Professor Dr. Schenk, formerly
Director of Garnier's Institute, an incident occurred which
will interest you. Singing was at first tried ; and afterwards
his brother-in-law, Philipp Schmidt, read long sentences from
Spiess's ' Turnbuch ' (Book of Gymnastics), which sentences
Philipp Eeis, who was listening, understood perfectly, and
repeated to us. I said to him, ' Philipp, you know that whole
book by heart ;' and I was unwilling to believe that his ex-
periment could be so successful unless he would repeat for
me the sentences which I would give him. So I then went
up into the room where stood the telephone, and purposely
uttered some nonsensical sentences, for instance : ' Die Sonne
ist von Kupfer ' (The sun is made of copper ), which Eeis
understood as, ' Die Sonne ist von Zucker ' (The sun is made of
sugar) ; ' Das Pferd frisst keinen Gurkensalat ' (The horse eats
no cucumber-salad) ; which Eeis understood as ' Das Pferd
frisst . . . .* (The horse eats . . . ). This was the last of
these experiments which we tried. Those who were present
were very greatly astonished, and were convinced that Eeis's
invention had opened out a great future.

" H. F. PETER, Musiklehrer."

128 PHILIPP REIS,

STEPHEN MITCHELL YEATES, ESQ.

[Mr. Yeates is a well-known instrument-maker in the city of Dublin,
and, in 1865, purchased from Mr. W. Ladd, of London, a Keis's Telephone
of the form shown in Keis's Prospectus (Fig. 29). Mr. Yeates, after a few
experiments, rejected the knitting-kneedle receiver, and replaced it by the
instrument shown in Fig. 42, which consisted of an electromagnet mounted

Fig. 42.

above a sound-box, having a vibrating armature furnished with an ad-
justing screw to regulate its distance from the poles of the electromagnet.
This instrument worked, even when the armature was in absolute contact
with both poles of the electromagnet, and as the magnet did not during
the experiments lose its hold on the armature, it was clear that the effects
were due to alterations in the intensity of the magnetism of the magnet.
The apparatus was shewn at the November meeting of the Dublin Philo-
sophical Society, when singing and words were transmitted. With a
careful adjustment- it was possible to distinguish all the quality of the
note sung into the transmitter and to distinguish the difference between
any two voices. The instruments were then sold to the late Eev. Mr.
Kernan, who was then Professor of Physics in Clongowes Wood College.
The following recent letter from Mr. Yeates corroborates the above facts.]

" 2, Grafton Street, Dublin,
"March 1st, 1883.

"DEAK SIR,

" There are several residing at present in Dublin who were
present at my telephonic experiments in 1865 ; three of them,
namely, Dr. W. Frazer, Mr. A. M. Vereker, and Mr. E. C.
Tuke, took an active part in the experiments, and remember all
the circumstances connected with them. The voice of each
was instantly recognised in the receiver ; in fact, this point
attracted special attention at the time.

INVENTOR OF THE TELEPHONE. 129

" I had no knowledge at that time that Eeis had used an
electromagnetic receiver, nor did I know that Eeis was the
inventor of the instrument which I got from Mr. Ladd.

" The original instrument made by me is, I believe, still
in the Museum at Clongowes Wood College. The President
kindly lent it to me some time ago, and I returned it to him
again after showing it to Professor Barrett. I have a cut
of this receiver, which I will send to you if it will be of any
use to you.

" Yours truly,

"S. M. YEATES."

WILLIAM FRAZER, ESQ., M.D.,

"20, Harcourt Street, Dublin,

"March IB, 1883.
" DEAR SIR,

" I have a distinct recollection of the Telephone. We had
a small private club meeting once each month for scientific
purposes. On referring to my note-books, I find that there
was a meeting on Thursday evening, October 5th, 1865. It
was held in Nassau Street, at the residence Mr. Horatio
Yeates, now in Australia, and brother of Mr. Stephen Yeates.
The Telephone was upstairs, in the third story of the house,
and the voice heard in the hall. Mr. Vereker, of the Bank
of Ireland, Mr. John Eigby, of rifle celebrity, the two Mr.
Yeates, and, I think, Mr. Tuke, were present with myself.
There were some othets, whom I cannot now recollect, but
our club was small.

" Eigby sang ' Patrick's Day ' and ' God save the Queen,'
and various questions were asked and answered. The sepa-
rate words were most distinct, the singing less so ; but there
was no difficulty in recognising the individual who spoke by
his voice1.

" Being much interested in the subject, I got Mr. Yeates to

130 PHILIPP REIS,

allow the apparatus to be shewn at a Conversazione (Presby-
terian Young Men's) at the Eotunda on October 12, at 8 P.M.
His assistant, Mr. Tuke, took charge of it that night. It
was placed in a side room off the main round room of the
buildings.

" I exhibited at the October 5th meeting of our club a
specimen termed ' Locust gum/ probably derived from some
Rdbinia, but really can tell you nothing more about it. There
is merely a brief note of it in my private memoranda.

" Yours, dear Sir,

Believe me very truly,

" WILLIAM FRAZER,

" Fellow and Examiner, Eoyal College of Surgeons,
" Ireland, Member of Council, Eoyal Irish
" Academy, &c."

" Silvanus P. Thompson, Esq., University College, Bristol."

INVENTOR OF THE TELEPHONE: 131

APPENDIX I.

COMPARISON OF REIS'S TRANSMITTERS WITH RECENT
INSTRUMENTS.

ANY one who compares together the many different forms
of Reis's Transmitters cannot fail to notice that amidst the
great variety of form, two essential points are preserved
throughout, the presence of which is fundamental. These
two essentials are, firstly, the tympanum to collect the voice-
waves, and, secondly, an electric mechanism, consisting of two
or more parts in loose or imperfect contact with each other,
and so arranged in combination with the tympanum that the
motions of the latter should alter the degree of contact, and
consequently interrupt, to a greater or less degree, the
current of electricity flowing between the contact-pieces. It
was of course familiar to all electricians, long before Reis,
that a bad, or imperfect, or loose contact in a circuit offered a
resistance and interrupted the flow of an electric current.
In all ordinary telegraphic and electric apparatus great care
was taken to avoid loose and imperfect contacts by using
clamping-screws and solid connectors. But Reis, having
made up his mind (see p. 77) that the action due to the
magnetising current must vary in a manner correspond-
ing with, and therefore proportional to, the vibrations of
the voice, utilised this property of imperfect contacts which
alter their resistance according to the degree of contact, by
arranging his mechanism so as to apply the voice to vary
the degree of contact. This was the essence of his trans-
mitters. In other words, he applied the voice to control or

K 2

132 . PEILIPP REIS,

moderate the strength of the current generated by a battery.
His " interrupters " may therefore with propriety be called
" electric current contact regulators ;" and put into technical
language, the essence of this part of his invention lay in the
combination with a tympanum of electric current regulators
working upon the principle of variable contact.

In another appendix is discussed the precise nature of that
which occurs at a point of variable or imperfect contact, and
which results in a corresponding change of electrical resist-
ance when the degree of contact is varied. Suffice it to say
here that it is impossible to vary the degree of contact be-
tween two bodies which are lightly pressing one against the
other, and through which an electric current is flowing,
without altering the resistance offered to the current by this
joint in the circuit. If the two surfaces are pressed together,
so that there is a good contact, the current flows more freely,
finding less resistance. If, on the other hand, by altering
the pressure or the amount of surface exposed, we change the
degree of contact and cause fewer atoms of one piece to touch
those of the other piece, the current meets with greater ob-
struction and cannot flow with such strength as before : it is
partially " interrupted," to use the expressive term employed
by Eeis.

Now this operation of varying the degree of pressure in
order to vary the resistance of the interrupter or contact regu-
lator, was distinctly contemplated by Reis. We find his
definite instructions, for example (see p. 75), for arranging
the relative lengths of the two parts of the curved lever in
one of his transmitters, so that the movement of one contact-
piece may act on the other contact-piece with the greatest
possible force ; in other words, he shortened his lever at the
working end, sacrificing its range of motion in order to get a
greater range of pressure at the contact-point.

It has often been said, but incorrectly, that Reis intended
his " interrupters " or contact regulators to make and break
the electric circuit abruptly in the manner of a telegraphic
key worked by hand. No doubt in the mouth of a profes-
sional telegraph operator the words "interrupting " the circuit,

INVENTOR OF THE TELEPHONE. 133

and " opening " and " closing " the circuit, do now-a-days
receive this narrow technical meaning. But Eeis was not
a professional telegraph operator : he did not (see p. 87)
even know the signals of the Morse code, and it is self-
evident that he did not use the terms in any such restricted
or unnatural sense as abrupt " make-and-break," because he
proposed at the outset to interrupt the current in a manner
represented by the gradual rise and fall of a curve, stating
emphatically in his very first memoir on telephony (p. 55),
that to reproduce any tone or combination of tones all that
was necessary was " to set up vibrations whose curves are
like those " of the given tone or combination of tones.
Moreover, in the construction of almost all his transmitters,
even in the very first — the model of the human ear — he pur-
posely introduced certain parts which could have no other
effect than to prevent the occurrence of complete breaks in the
continuity of the current. In fact, instead of using rigid
supports for his interrupter, he mounted one or both of the
contact-parts with springs, so that one should follow the move-
ment of the other with a gentle pressure never amounting to
absolute break, except perhaps in the accidental case of a too
loud shout. By employing these following-springs, he intro-
duced, in fact the element of elasticity into his interrupter ;
and clearly he introduced it for the very purpose of avoiding
abrupt breaking of the contact. In the first form Fig. 5, p. 16
(the " ear "), there was one spring ; in the fourth form, Figs. 9
and 10, p. 21 (the "bored block"), there were two springs,
one of steel, curved, and one, a straight but springy strip, of
copper ; in the eighth form (the " lever " form), Fig. 14, p. 25,
there were two springs ; in the ninth form, Fig. 15, p. 26,
there was a springy strip of brass. In the final form, Figs.
17 and 18, p. 27 (the " square-box " pattern), there was, it
is true, a springy strip of copper, but the light adjustment of
contact was in this form obtained, not by a spring, but by
•the inertia of the upper contact-piece which by its own
weight pressed gently upon the lower contact-piece. In
every one of these forms, except the last, there was moreover
an adjusting-screw to determine the exact degree of initial

134 PEILIPP EEIS,

pressure between the contact surfaces. Doubtless the diffi-
culty of adjusting this screw to give the exact degree of con-
tact, enhanced as that difficulty was in consequence of the
liability of the membraneous tympanum to become flaccid
by the moisture of ohe breath, induced Eeis to think that
the later form of the apparatus in which this adjustment
was no longer retained would be more easy to use, or, as
he says in his Prospectus, more accessible to others. Yet
undoubtedly the absence of the spring at the contacts led
some persona to fancy that the instrument was intended to
be shouted or sung to so loudly that every vibration should
make the upper contact-piece jump up from the lower,
and as Professor Miiller even suggests (p. 98), produce a
spark ! But such a manner of using the instrument would
entirely defeat Eeis's most fundamental principle, that the
interruptions should be such as to correspond to the undu-
lating curve which represents the pressure due to vibration
of the sound-wave; the possibility of representing the de-
gree of pressure by a curve being one of the two principles
set forth in his paper " on Telephony " (p. 55), in which he
remarks, that " Taking my stand on the preceding principles,
I have succeeded in constructing an apparatus by means of
which I am in a position to reproduce .... even to a cer-
tain degree the human voice." Eeis was perfectly well aware,
as his curves show, that a complicated sound-wave does not
consist invariably of one condensation followed by one rare-
faction, but that there are all sorts of degrees of condensation
which may follow one another, and all capable of being
represented by a curve. If all sounds consisted of one rare-
faction following immediately after each one condensation
there might be some propriety in proposing that after each
" make " of contact there should be a " break " in the sense
of an abrupt or complete breach in the continuity of the
current. But, obviously, the fact that one condensation may
follow another without a rarefaction between (which Eeis's
curves show that he knew) must be amply sufficient to prove
that on Eeis's own principle his interrupter was meant to
produce variations in the degree of contact in exact corre-

INVENTOR OF THE TELEPHONE. 135

spondence with the variations in the degree of pressure, whatever
these might be. Had he not meant this, he could not have
talked about " taking his stand " on the principle of repre-
senting varying pressures by an undulatory curve. Now,
from what has been adduced, the following points are clear :—

Firstly, that the contact-regulator which Eeis combined
with the tympanum was meant to interrupt the current, more
or less, according to the varying movements imparted to it by
the voice.

Secondly, that Eeis intended such interruptions or varia-
tions of contact to be proportional to, or to " correspond "
with, the variations indicated by the undulatory curve of
varying pressures.

Thirdly, that for the purpose of preventing the occurrence
of abrupt breaks in the continuity of the circuit, he used
springs and adjusting screws, and in one form availed himself
of the inertia of the moving parts to attain a similar end.

It is also clear from his own prospectus, that he was aware
that for the simpler and ruder purpose of transmitting
musical airs, in which the number of the vibrations is the
only consideration and where each single condensation is
actually followed by a rarefaction, actual abrupt breaks in
the continuity of the circuit are admissible. Eeis chose this
simple case as the one capable of being readily grasped by a
general audience, though it was obviously only a partial ex-
planation of the action of the apparatus in the simplest case
that could be presented.

Turning now to some of the more modern transmitters,
we will inquire how far Eeis's fundamental principles are
involved in their construction. We will first take Berliner's
transmitter, of which Fig. 43 is a drawing, reproduced from
the sketch in the specification of his British Patent. This
transmitter consists of a tympanum of thin metal to collect
the sound-waves, and behind it is attached an interruptor or
current regulator, identical in almost every respect with that
of Eeis. One of the contact-pieces, marked Ey circular in
form, is fixed to the centre of the tympanum, and vibrates

136

PEILIPP KEIS,

Fig. 43.

with it, precisely as in Eeis's latest, and in some also of his
earlier instruments. Against this there rests in light contact
a second contact-piece, in the form of a small
blunt spike, F, screwed into a short arm,
loosely jointed to the part JV, where the
circuit is connected. As in Eeis's latest
transmitter (Fig. 17, p. 27), so here, the
contact-pieces are kept in contact by gravity.
When any person talks to the tympanum it
vibrates, and, as a result, the degree of con-
tact between the two surfaces is varied,
resulting in a greater or less interruption of
the current, the inertia of the upper contact-
piece, serving to prevent complete abrupt
<f break" of the circuit, except under un-
usually strong vibrations. In fact, if the
speaker talks too loudly when speaking into
Berliner's transmitter, he will cause abrupt
breaks to occur instead of partial interruptions ; and a rattling
noise comes in to confuse the speech at the receiving end of
the line. But this is precisely what occurs in a Eeis's trans-
mitter if one talks too loudly to it. It is obvious that if
Berliner's transmitter is a " make-and-break " instrument, so
is Eeis's, because the principle of action is identical : and
it is also obvious that if Berliner's instrument is capable of
varying the resistance at the contact-points by interrupting
the current in a manner corresponding to the pressures of
the air in the sound-waves, so also is Eeis's instrument.

It is a fact that in Berliner's instrument it is usual to
make the contact-pieces, or one of them, of hard artificial
coke-carbon, as this substance will neither fuse nor rust. But
Berliner's transmitter will transmit speech perfectly if the
contact parts be of brass, silver, platinum, carbon, or almost
any other good conductor. In most of Eeis's instruments
the contact-pieces were usually of platinum ; but they work
quite as well if artificial coke-carbon is substituted. In fact,
Eeis's principle of variable and elastic contact is applicable
to contact-pieces of any material that is a good enough con-

INVENTOE OF THE TELEPHONE.

137

ductor of electricity and hard enough for the purpose. The
main improvement in Berliner's transmitter is the substi-
tution of the metal tympanum for the membraneous one,
which was liable to become flabby with moisture.

We pass on to Blake's transmitter, which is the one more
generally used in Great Britain than any other. The draw-
ing, Fig. 44, of this instrument is taken from the specifica-
tions of Blake's British Patent, and shews all that concerns
the contact-parts. It does not show
the accessories, the induction-coil, or
the form of adjusting screw and frame
peculiar to this instrument. Inspec-
tion of the figure shows that this trans-
mitter consists of a mouthpiece in the
form of a conical hole bored through a
stout plank of wood, and closed at the
back by a metal tympanum of exactly
the same size as that of Eeis, behind
which the interrupter is placed, pre-
cisely as in some of Eeis's instruments.
In this interruptor both the contact-parts
are supported on springs, resembling,
even in the curve given to them, the
springs Eeis used. The first of the con-
tact-pieces is a small metal spike. Con-

Fig. 44.

cerning it Mr. Blake remarks (page 4 of Specification) : — " It is
desirable that it should be formed of, or plated with, some metal,
like platinum or nickel, which is not easily corroded. It may
be attached directly to the diaphragm, but I prefer to support
it independently, as shewn, upon a light spring." ..." This
method of supporting the electrode ensures its contact with the
other electrode under some circumstances when otherwise they
would be liable to be separated and the circuit broken." In fact
this spring serves functions precisely identical with those of
the springs used by Eeis. The second of the contact-pieces may
be described as a mass of metal at the end of a spring. Of it
the patentee remarks : — " This weight may be of metal which
may serve directly as the electrode, but I have obtained better

138 PHILIPP REIS,

results by applying to it, at the point of contact with the
other electrode, a piece of gas-coke or a hard-pressed block
of carbon." As a matter of fact, a mass of silver or of nickel or
of platinum will transmit talking perfectly, but these metals,
though better conductors, are more liable to corrode and fuse,
and may require therefore more frequent renewal, than gas-
coke. Since, then, it is immaterial to the action of a Blake
transmitter what substance is used for the contact-pieces, it
is clear that the principle of employing an interrupter
mounted on springs is the real feature of the instrument.
Eeis also mounted his interrupters with springs, and for the
very same purpose. The function of the weight on the second
spring of the Blake transmitter is to resist the movement of
the tympanum, and to " modify by its inertia the variations
of pressure" between the two contact-pieces. In other
words, it acts partly as Berliner's transmitter, by inertia. So
did one of Eeis's instruments, as we have seen. In the Blake
instrument there is the happy idea of applying both the spring-
principle and the inertia-principle at once. Yet, in spite of
this, if the speaker shouts too loudly into a Blake transmitter,
he will cause abrupt breaks between the contact-pieces in-
stead of producing partial interruptions in the contact, and
in that case speech will, as heard at the other end of the line,
be spoiled by a rattling noise. It is possible, also, with
Eeis's instruments to spoil the articulation by shouting too
loudly, and causing actual abrupt breaks in the continuity.
If Blake's interrupter can be worked as a make-and-break
in this sense, so can Eeis's : for there is not one of the
features which is essential to Blake's instrument that cannot
be found in Eeis's also.

By way of further carrying out the comparison between
Eeis's methods of combining his tympanum with his contact-
regulator, and the methods adopted by later inventors, we
give, in Fig. 45, ten comparative sketches, the first five of
which illustrate Eeis's methods. In these sketches the only
liberty taken is that of representing no more of the instru-
ments than the actual parts wanted in the comparison. No. 1
represents the working-parts of Eeis's first model ear, with

INVENTOR OF THE TELEPHONE.

139

its curved lever, platinum-tipped spring, and adjusting screw.
No. 2 shows the springs, screw, and contact-pieces of Eeis's
bored-block transmitter (" fourth form : " compare Figs 9 and
10, p. 21). No. 3 shows the curved lever, the springs, and

Fig. 45.

the adjusting screw of Eeis's eighth transmitter (" lever "
form). No. 4 gives the working parts of Eeis's ninth trans-
mitter, described in detail on p. 27. No. 5, in which the
tympanum is placed in a vertical position, merely for con-
venience of comparison with the other figures, shows the

140 PHILIPP KEIS,

working parts of Eeis's final form of instrument, in which
gravity and the inertia of the upper contact-piece enabled
him to dispense with the adjustment of spring and screw.
No. 6 shows in profile Berliner's transmitter, which may be
instructively compared with No. 5. No. 7 shows the working
part of Blake's transmitter, which should be compared with
Nos. 2 and 4 : even the curve of the springs imitates that
adopted by Keis. Nos. 8, 9, and 10 are forms of transmitter
devised by Edison. No. 8 is copied from Fig. 10 of the speci-
fication of Edison's British Patent. It will be seen that here
there is an interruptor placed on each side of the tympanum,
and that each interruptor consists of a short spike mounted
on a spring and furnished with an adjusting-screw. " Platina
foil disks," says the inventor, are to be secured to each
side of the diaphragm, and against these disks, as in Eeis's
instruments, press the contact-points of the interrupters.
The patentee also states (p. 7 of his Specification), that
for these contact-points " any substance not liable to rapid
decomposition " may be used. This term includes all the
substances used by Eeis, and a great many others. It will
therefore be seen that this whole device is nothing more than
a Eeis transmitter with the contact parts duplicated. Yet this
instrument was intended by Edison to transmit speech, and
will, like Eeis's instrument, transmit speech if properly used.
No. 9 of the set of sketches is taken from Fig. 25 of Edison's
British Specification, but omits the induction-coil and other
accessories, retaining the parts wanted for comparison. The
patentee thus describes the parts figured. "The tension-
regulator [meaning thereby the interruptor or contact-regu-
lator] is made of platina-foil upon the surface of two soft
rubber tubes ; one on the diaphragm, the other on the
adjusting-screw." It is interesting to note here how the
ingenuity of the later inventor led him to vary the construc-
tion adopted by the original inventor in substituting an
elastic cushion of soft rubber for the springs of the older
instruments. But the principle of combining a tympanum
with a contact-regulator, which was Eeis's fundamental
notion, is here also the leading idea ; and the further idea of

INVENTOR OF THE TELEPHONE. 141

obviating abrupt breaks in the current by applying elastic
supports is also carried out. Edison even copies Eeis in
having an adjusting-screw, and he applies the very same
substance— platinum foil — which Keis used in his very first
and his very last transmitter. Edison's transmitter transmits
speech very fairly, even without any of such later accessories
as induction-coils ; and why should it not ? It is constructed
on the very lines, nay, with details almost identical with
those prescribed by Keis in describing his invention. It
embodies those fundamental ideas which Eeis set before
him when he said, "Taking my stand upon the preceding
principles, I have succeeded."

The last of the ten sketches of Fig. 45 is taken from
Edison's first American Patent specification [No. 203,014,
filed July 20, 1877], and shows a duplicated interrupter
with springs and adjusting-screws combined with a tym-
panum. Further comment on this arrangement is needless,
save to remark that in this patent for " speaking telegraphs,"
Edison himself describes the contact-apparatus which Eeis
termed an " interrupter," as a " circuit-closer," or in another
place as " circuit-breaking connections," and, in his British
Patent quoted above, as a " tension-regulator." It is
evident that if Eeis could transmit speech by an interrupter
which closed and opened the circuit (always in proportion
to the vibrations) there is 110 reason why Edison seventeen
years afterwards should not accomplish the same result by a
similar means. But it has lately been fashionable to deny
that any such device as an interrupter mounted on springs
can transmit speech at all !

We have now compared with Eeis's transmitters several
of the more modern inventions. It would be possible to carry
comparison further were that course needed. We have not
thought it worth while to rake up Edison's now discarded
lamp-black button transmitter ; and we have not yet spoken
of Crossley's transmitter nor of Theiler's transmitter, nor of
their parent the Hughes' microphone, nor of dozens of other
forms. In some of these there is no specific " tympanum,"
but only a sounding-board of pine-wood, and in most of them

142 PHILIPP REIS,

the points of loose-contact, where interruption more or less
complete may occur, are multiplied. But they all come back
in the end to Eeis's fundamental idea, namely that of setting
the voice to vary the degree of contact in a mechanism
which he called an interruptor, and which others have called
a current-regulator (or, less correctly, a tension-regulator)
which, because the degree of contact between its parts was
varied, caused those parts to offer more or less resistance to
the flow of the current, and thereby threw it into vibrations
corresponding to those of the sound-wave impressed upon
the tympanum. There is not a practical transmitter used in
any of the telephone exchanges of Great Britain to-day that
does not embody this principle.

Keis did, indeed, penetrate to the very heart the principles
necessary to be observed in a successful telephone. He was
master of the situation. For, as in every practical trans-
mitter in use to-day, so in his transmitter, there was a loose
contact in the circuit so arranged that the voice could act upon
it, and thereby regulate the strength of the current. If you
eliminate this part of the apparatus, — screw up the loose-
contacts of your transmitters, so that your voices cannot
affect them, — what will your telephones be worth ? No :
the essential principle of the transmitter — " Das Telephon "
emphatically as its inventor styled it — is variable contact;
and that all-essential principle was invented and applied for
the purpose of transmitting speech by Philipp Eeis in 1861.

If this does not suffice as a claim for the invention of the
Telephone transmitter, it may well be wondered what will.
We can dispense with all other features save this one. We
can even dispense with the tympanum or diaphragm which
Eeis introduced, and can operate on the contact-parts without
the intervention of this part of the combination. We can use
the very metals which Eeis used, and dispense with lamp-
black and all the fallacious rubbish that has been subsequently
devised about semi-conductors, whatever that term may mean.
We can even dispense with springs and adjusting screws.
But with the principle of variable contact we can not dispense.
That which alone is indispensable Philipp Eeis discovered,

INVENTOR OF TEE TELEPHONE. 143

APPENDIX II.

ON THE VARIATION OF ELECTRIC EESISTANCE AT A POINT OF
IMPERFECT CONTACT IN A CIRCUIT.

EVER since electricians had experimented with voltaic
currents, and especially since the introduction of 'the electric
telegraph, it had been a familiar fact that a loose or imper-
fect contact in the circuit caused a resistance to the flow of
the current and interrupted it more or less completely. To
obviate the occurrence of loose or imperfect contacts, binding-
screws were invented ; and many were the precautions taken
to make tight contacts at joints in the line, the resistance of
which it was desirable to maintain at a minimum. Young
telegraphists were particularly instructed to press their keys
well down in signalling, because a light contact would offer
gome resistance which, on an increase of pressure, would dis-
appear. In fact, it was generally well known that the resist-
ance of two pieces of metal or other conducting material in
contact with one another might be made to vary by varying
the goodness or badness of the contact with the application of
more or less force. This fact was known to apply to good
conductors, such as copper and other metals, and it was known
to apply also to non-metallic conductors, such as plumbago.
Plumbago points were used by Yarley for the contacts of
relays ; it having been found that points of platinum were
liable to become fused together with the passage of the
current, and by so sticking rendered the instrument useless.
Since plumbago was known to be infusible, it was hoped that
a plumbago contact would prove more reliable. In practice,

144 PHILIPP REIS,

however, the plumbago relay did not turn out so well. True
it did not fuse, or stick, or rust ; but it was even more liable
than platinum to form imperfect contacts, the resistance of
the light contact being so high that a sufficient current did
not pass. It is not known whether other non-metallic sub-
stances were tried ; probably not, because of non-metallic
substances plumbago is one of the few that are good con-
ductors.

According to Edison (British Patent, No. 792, 1882),
compressed graphite is a substance of great conductivity.
According to Faraday (' Exp. Kes.' vol. i. p. 24), retort-carbon
is an excellent conductor. Both graphite and retort-carbon
agree with the metals in the property that the electric resist-
ance offered at a point of contact between them varies when
the pressure at the contact is varied. It is indeed remarkable
through what wide ranges of resistance the contact between
two good conductors may vary. The resistance of contact
between two pieces of copper may be made to vary in a per-
fectly continuous manner by changes of pressure through a
range, according to Sir W. Thomson, from a small fraction of
one ohm, up to a resistance of many thousand ohms. The
same is true of silver, brass, and many other good conductors,
including graphite and retort-coke, though with the .latter
materials the range of resistances is not so great. "With par-
tial conductors, such as oxide of manganese, sulphide of
copper, sulphide of molybdenum, &c., and with bad con-
ductors, such as lamp-black and selenium, whose conduc-
tivity is millions of times less than that of graphite, copper,
and other good conductors, it is impossible to get equally
wide variations of resistance, as the amount of pressure at a
point which will bring the bad conductors into intimacy of
contact, will not turn them into good conductors. Platinum
being in the category of good conductors, is amongst those
substances which yield a very wide range of electrical resist-
ances at the contact-points which are submitted to varying
pressures,

With the very highest conductors, such as silver and
copper, the electrical range of contact-resistance is higher

INVENTOR OF THE TELEPHONE. 145

than with those of lesser conductivity, such as lead, platinum,
graphite, and retort-coke.

But though the range of variation in electrical resistance at
contacts is highest for the best conductors, there comes in
another element, namely, the range of distance through which
the contact-pieces, or either of them, must be moved in order
to pass through the range of variations of resistance. This is
quite a different matter, for here the best conductors have
the smallest range, and some that are not so good a greater
range. In any case the available range of motion is
very small — to be measured in minute fractions, — millionth-
parts, perhaps, — of an inch. So far as experiments go, how-
ever, silver has the smallest range of all, then gold, then
copper. Platinum and nickel have a considerably wider
range, plumbago and retort-coke a still wider one.

It is an extremely difficult matter to decide what is the
precise nature of that which goes on at a point of contact
between two conductors when the pressure at the point is
altered. The principal suggestions hitherto advanced have
been that the change of resistance observed is due : —

(a) To the mere changes in the amount of surface in contact,
(ft) To a change in the resistance of the substance of the
conductor itself.

discharge.

(d) To the change in the thickness of the intervening film

of air.

(e) To the change in resistance of the parts in contact con-

sequent on the evolution of heat by the current.

It is admitted that this last suggestion, though it might
account for a difference between different substances, in so
far as they differ from one another in the effect of heat upon
their specific resistance, implies as a preliminary fact that
the amount of surface in contact shall be varied by the pres-
sure. No convincing proof has yet been given that the
alleged layer of air or other gases has any real part to play
in the phenomena under discussion. Nor can the hypothesis,

146 PHILIPP KEIS,

that minute voltaic arcs are formed at the contact be regarded
as either proven or probable.

The only two theories that have really been investigated
are (a) and (b) of the above series. Of these two (&) is cer-
tainly false, and (a) is probably, at least to a very large
extent, true.

It is often said by persons imperfectly acquainted with the
scientific facts of the case, that carbon is used in tele-
phone-transmitters, because the resistance of that substance
varies with the pressure brought to bear upon it, whilst with
metals no such effect is observed. This statement, taken
broadly, is simply false. Mr. Edison has, indeed, laid claim
to the " discovery " (vide Prescott's ' Speaking Telephone,'
p. 223), that " semi-conductors," including powdered carbon
and plumbago, vary their resistance with pressure. All that
Mr. Edison did discover was that* certain substances, whose
properties of being conductors of electricity had been known
for years, conducted better when the contact between them
was screwed up tightly than when loose. The experiments
made to test this alleged " property " of carbon are absolutely
conclusive. The author of this book has shown * that when
a rod of dense artificial coke-carbon, such as is used in many
forms of telephone transmitters, such as Crossley's for
example, is subjected to pressure varying from less than one
dyne per square centimetre up to twenty-three million times
that amount, the resistance of the rod did not decrease by so
much as one per cent, of the whole. In this case any doubt
that might have been introduced by variable contact was
eliminated at the outset by taking the precaution of electro-
plating the contacts.

In 1879, Professors Naccari and Pagliani, of the University
of Turin, published an elaborate series of researches f on the
conductivity of graphite and of several varieties of coke-carbon,
and found, even with great changes of pressure, that the
changes of electric resistance were practically too small to be

* « Philosophical Magazine,' April 1882.

f ' Atti del R. Istituto Veneto di Scienze,' vol. vi. ser. 5.

INVENTOE OF THE TELEPHONE. 147

capable of being measured, and that the only changes in
resistance appreciable were due to changes of contact.

In January 1882, Mr. Herbert Tomlinson communicated to
the Eoyal Society * the results of experiments on a number
of electric conductors. The change of conductivity by the
application of stress was found to be excessively small. For
carbon it was less than one-thousandth part of one per cent,
for an increase of fifteen Ibs. on the square inch in the pressure.
For iron it was slightly greater, and for lead nearly twice as
great, but with all other metals less. If this alleged pro-
perty were the one on which the action of telephone trans-
mitters depended, then lead ought to be twice as good a
substance as graphite ; whereas it is not nearly so good.

Professor -W. F. Barrett, in 1879,f made some experiments
on the buttons of compressed lamp-black used in Edison's
transmitter, and found that when an intimate contact was
satisfactorily secured at the beginning, " pressure makes no
change in the resistance."

In the face of all this precise evidence, it is impossible to
maintain the theory that the electric resistance of plumbago
or of any other such conductor varies under pressure. The
only person who has seriously spoken in favour of the theory
is Professor T. C. Mendenhall, but in his experiments he took
no precautions against variability of contacts, so that his
conclusions are invalid.

More recently still, Mr. 0. Heaviside and Mr. Shelf ord
Bidwell have experimented on the variations of resistance at
points of contact.:]: Mr. Heaviside's experiments were con-
fined to contacts between pieces of carbon, and though ex-
tremely interesting as showing that the resistance of such
contacts are not the same, even under constant pressure, when
currents of different strength are flowing, do not throw much
light on the general question, because they leave out the
parallel case of the metals. Mr. Bidwell's very careful
researches were chiefly confined to carbon and bismuth. The

* Proc. Koy. Soc. No. 218, 1882.

f See Proc. Roy. Dubl. Soc. Feb. 17, 1879.

t Vide ' The Electrician,' Feb. 10, 1883.

L 2

148 PHILIPP REIS,

choice is unfortunate, because bismuth the most fusible and
worst conductor amongst metals (save only quicksilver) is
the one metal least suited for use in a telephone transmitter.
Mr. Bidwell's conclusions, so far as they are comparative
between carbon and " the metals," are therefore necessarily
incomplete.

Professor D. E. Hughes, whose beautiful invention, the
Microphone, attracted so much attention in 1878, has lately
thrown the weight of his opinion in favour of the view that
with carbon contacts the effect is due chiefly to an electric
discharge or arc between the loosely-contiguous parts. But
Professor Hughes' s innumerable experiments entirely upset
the false doctrine that a "semi-conductor" is necessarily
required for the contact-parts. Speaking recently,* he has
said : " I tried everything, and everything that was a con-
ductor of electricity spoke." In 1878, in a paper " On the
Physical Action of the Microphone," Professor Hughes
stated : f " the best results as regards the human voice were
obtained from two surfaces of solid gold." Hughes also
found carbon impregnated with quicksilver in its pores to
increase its conducting power to work better than non-
metallised carbon of inferior conductivity. Quite lately
Mr. J. Munro has constructed successful transmitters of
metal gauze, having many points of loose-contact between
them.

It seems, therefore, much the most probable in the present
state of investigations, that the electric resistance of a contact
for telephonic purposes is determined solely by the number
of molecules in contact at the surface, and by the specific
conductivity of those molecules. The element of fusibility
comes in to spoil the constancy of the surfaces in action ;
and hence the inadmissibility of general conclusions with
respect to all metals drawn from the behaviour of the most
fusible of them. At a mere point in contact physically with
another point, there may be hundreds or even millions of

* Journal Soc. Telegr. Engin. and Electricians, vol. xii. p. 137.
t Proc. Physical Soc. vol. ii. p. 259, 1878.

INVENTOR OF TEE TELEPHONE. 149

molecules in contact with one another, all acting as so many
paths for the flow of the electric current. An extremely
small motion of approach or recession may suffice to alter
very greatly the number of molecules in contact, and the
higher the specific conductivity of the substance, and the
denser its molecules, the shorter need be the actual range of
motion to bring about a given variation in the resistance
offered. Just as in a system of electric lamps in parallel arc,
the resistance of the system of lamps increases when the
number of lamps through which the current is flowing is
diminished, and diminishes when the number of lamps con-
necting the parallel mains is increased; so it is with the
molecules at the two surfaces of contact. Diminishing the
number of molecules in contact increases the resistance,
and vice versa. Each molecule as it makes contact with a
molecule of the opposite surface diminishes, by so much rela-
tively to the number of molecules previously in contact, the
resistance between the surfaces. Each molecule as it breaks
from contact with its opposite neighbour adds to the resistance
between the contact-surfaces. It may therefore be that the
variations of resistance which are observed at contacts between
all conductors, from the best to the worst, are all made up,
though they appear to pass through gradual and continuous
changes, of innumerable minute makes-and-breaks of mo-
lecular contact. The very minuteness of each molecular
make-or-break, and the immense number that actually must
occur at every physical " point " of contact, explain why the
effect seems to us continuous. We owe, moreover, to Mr.
Edison * the experimental proof that actual abrupt makes-
and-breaks of contact can produce an undulating current
when they recur very rapidly. Whether the heating action of
the current itself may not also operate in changing the con-
ductivity of the molecules which happen at the moment to be
in contact is another matter. It may be so; but if this
should hereafter be demonstrated, it will but confirm the
contact-theory of these actions as a whole.

* ' Journal Soc. Telegraphic Engineers,' vol. iv. p. 117, 1874.

150 PHILIPP REIS,

Assuming, then, broadly, that the observed resistance at a
point of contact is due to the number of molecules in contact
and to their individual resistances, it is evident that the
property of varying resistance at contact ought to be most
evident, ceteris paribus, in those substances which are the best
conductors of electricity. Unfortunately, the cetera are not
paria, for the question of fusibility comes in to spoil the
comparison ; and carbon, which has less fusibility than the
metals, is commonly credited with giving a better result than
any. This common opinion is, however, based on comparisons
made without taking into consideration the question of range
of motion between the parts in contact, and without taking
into consideration the point that whilst some forms of carbon
are excellent conductors, others do not conduct at all. In
a telephonic transmitter so arranged that the actual range
of motion shall be very small, the metals are just as good
as carbon — some of them better. I have heard from a trans-
mitter with contacts of pure bright silver better articulation
than with any carbon transmitter. And this is exactly what
theory would lead one to expect. As to the suggestion that
plumbago makes a successful transmitter, because it is a
" semi-conductor " — whatever that term may mean * — it is
one of those suggestions which are peculiarly fitted to catch
the unscientific mind as affording an easy explanation for an
obscure fact ; unfortunately, like a good many other similarly
catching suggestions, it is not true. The very best conductor
— silver — will serve to transmit articulate speech: and so
will the one of the very worst conductors — lamp-black ! So
much for this fallacious doctrine of semi-conductors !

* The term " semi-conductor " is very rarely used by electricians, who
prefer the term " partial conductor " as being more correct. Moreover,
electricians, from Faraday downwards, are practically agreed in calling
plumbago a good conductor, and worthy of being classified by reason of its
high conductivity along with the metals. The substances known as
" semi-conductors " are those given in Ferguson's * Electricity,' p. 49
(edition of 1873), namely, alcohol, ether, dry-wood, marble, paper, straw,
and ice. Mascart and other eminent authorities agree in this classification.
It would tax even Mr. Edison's unrivalled ingenuity to make of these
materials a transmitter that should alter its resistance by pressure !

INVENTOR OF THE TELEPHONE. 151

Eeis used for his contact-points substances which, by reason
of their non-liability to fuse or oxidize, were customary in
electrical apparatus, and chiefly platinum. In his earliest
transmitter (model ear), and in his last, platinum was used.
In his lever-form of transmitter, so minutely described by
von Legat, the material is not specified. The lever-shaped
contact-piece was to be a conductor, and as light as possible,
and since all metallic parts are particularly described as
metallic, whilst this is not so described, the obvious inference
is that this was non-metallic. The number of light, non-
metallic conductors is so few that the description practically
limits choice to some form of hard carbon. No other ma-
terials are named by Eeis, but Pisko says (p. 103) that brass,
steel, or iron might be used for contacts. Any one of these
materials is quite competent, when made up into properly-
adjusted contact-points, to vary the resistance of a circuit
by opening and closing it in proportion to the vibrations
imparted to the contact-points. That is what Eeis's trans-
mitter was intended to do, and did. That is what all the
modern transmitters — Blake's, Berliner's, Crossley's, Gower-
Bell's, Theiler's, Johnson's, Running's do, even including
Edison's now obsolete lamp-black button transmitter. Mr.
Shelford Bidwell has very well summarized the action of the
current-regulator in the following words: "The varying
pressure produces alterations in the resistance at the points
of contact in exact correspondence with the phases of the
sound-waves, and the strength of a current passing through
the system is thus regulated in such a manner as to fit it for
reproducing the original sound in a telephone."

Eeis constructed an apparatus consisting of a tympanum
in combination with a current-contact-regulator, or " inter-
rupter," which worked on this principle of variable contact,
and he called it " The Telephone " (see pp. 57, 85). The very
same apparatus we now-a-days call a " Telephone-trans-
mitter," or simply a " transmitter." It is curious to note
that Eeis seems to have regarded his receiver or " reproducing-
apparatus" as no new thing. He says explicitly (p. 56)
that his receiver might be replaced by " any apparatus that

152 PHILIPP REIS,

produces the well-known galvanic tones." " The Telephone "
was with Eeis emphatically the transmitter. Bell in 1876
invented an instrument which would act either as transmitter
or receiver, and which, though never now used as trans-
mitter, is still called " a Telephone." Edison's " sound-tele-
graph," or "telegraphic apparatus operated by sound," was
patented in 1877. In his specification lie never called his
transmitter a " telephone ; " that name he reserved exclusivelv
for his receiver. He found it, however, convenient a year
later to rechristen his transmitter as the " carbon telephone"
though throughout the whole of his specification neither
"carbon1' nor "telephone " are mentioned in connection with the
transmitter ! Within that year Hughes had brought out
another instrument — " The Microphone " — which, like Eeis's
instrument, embodied the principle of variable contact.
Hughes's instrument, usually constructed with contacts made
of loose bits of coke-carbon, was simply a Eeis's Telephone
minus the circular tympanum ; and the really important new
fact it revealed, was that very minute vibrations, such as those
produced by the movements of an insect, when transmitted
immediately through the wooden supports, sufficed to vary the
resistance of a telephonic circuit, though far too slight in
themselves to affect it if they had to be first communi-
cated to the air and then collected by a tympanum. Put a
specific tympanum to a Hughes's microphone, and you get a
Eeis's telephone. Take away the tympanum from a Eeis's
telephone, and you get a Hughes's microphone. Hughes is
not limited to one material, nor is Eeis. But the fundamental
principle of the electrical part of each is identical. The Blake
transmitter (Fig. 44), and the Berliner transmitter, and also
Liidtge's microphone,* which was even earlier than that of
Hughes, are all embodiments of the same fundamental
principle of variable contact which Eeis embodied in his
" Telephone."

The numerous experiments which Eeis made, and the many

* Liidtge's German Patent, dated Jan. 12, 1878, describes a " Universal
Telephone " in which a tympanum was applied to convey vibrations to an
interrupter made of hard coke-carbon.

INVENTOR OF THE TELEPHONE. 153

forms of instruments which he devised, prove his conviction
of the importance of his invention to have been very
deeply rooted. He had indeed penetrated to the very soul
of the matter. He did not confine himself to one kind of
tympanum, he tried many, now of bladder, now of collodion,
now of isinglass, and now of thin metal. He varied the forms
of his instruments in many ways, introducing the element of
elasticity by springs and adjusting-screws. Though he
chiefly employed one metal for his contact-pieces, he did not
limit himself to that one, but left us to infer that the principle
of variable contact was applicable to any good conductor,
metallic or non-metallic. He knew better, indeed, than to
limit himself in any such fashion ; better, indeed, than some
of the eminent persons who are now so willing to ignore his
claims. Modern practice has taught us to improve the
tympanum part of Eeis's invention, and to obviate the incon-
veniences to which a membrane is liable : in that part we have
gone beyond Eeis. But in the question of contact-points
for opening and closing the circuit in correspondence with
the vibrations, we are only beginning to find how much Eeis
was a-head of us. We have been thrown off the track —
blinded perhaps — by the false trail of the " semi-conductor "
fallacy, or by the arbitrary and unnatural twist that has been
given by telegraphists to Eeis's expression, " opening and
closing the circuit," forgetting that he practically told us that
this operation was to be proportional to, " in correspondence
with," the undulations of the tympanum. When we succeed
in freeing ourselves from the dominance of these later ideas,
we shall see how much we still have to learn from Philipp
Eeis, and how fully and completely he had grasped the
problem of the Telephone.

154 PHILIPP EEIS,

APPENDIX III.

COMPARISON OF REIS'S RECEIVERS WITH RECENT INSTRUMENTS.

THE receivers invented by Reis for the purpose of reconvert-
ing into audible mechanical vibrations the varying electric
currents transmitted from the speaking end of the line were
of two classes, viz. :

(1.) Those in which the magnetic expansion and contraction
of a rod of steel or iron, under the influence of the varying
current, set up mechanical vibrations and communicated them
to a sound-board.

(2.) Those in which the current by passing round the coils
of an electro-magnet caused the latter to vary the force with
which it attracted its armature, and threw the latter into
corresponding mechanical vibrations.

The first of these principles is embodied in the " knitting-
needle " receiver described above and depicted in figures
22 & 23 on page 33. This receiver differs wholly from
the later instruments of Bell, and others, and depended for
its action upon the phenomenon of magnetic expansion
discovered by Page and investigated by Joule. It was well
known before Reis's time that when a needle or bar of iron
was magnetised it grew longer, and when demagnetised it
grew shorter. Page detected the fact by the " tick " emitted
by the bar during the act of magnetisation or demagnetisation.
Joule measured the amount of expansion and contraction.
To these discoveries Reis added two new facts ; first, that if
the degree of magnetisation be varied with rapid fluctuations
corresponding to those of the sound waves impressed on the

INVENTOE OF THE TELEPHONE. 155

transmitter, the expansion and contraction of the rod followed
these fluctuations faithfully, and therefore emitted at the
receiving end sounds similar to those uttered at the trans-
mitter. Secondly, by employing a needle of steel instead of
the bar of iron used by Page, Eeis obtained an instrument
which once used could never become completely demagnetised
on the cessation of the current ; it was thenceforth & permanent
magnet, and all that the fluctuating currents could do was to
vary its degree of magnetisation. Eeis carefully explained
in his memoir " On Telephony," how the frequency of such
fluctuations in the magnetising current could act in repro-
ducing the pitch, and further, how the amplitude of the
fluctuations set up vibrations of corresponding amplitude in
the rod : he added with significance, that tl^e quality of the
reproduced note depended upon a number of variations of
amplitude occurring in a given time. His theory of these
actions was that the atoms (or perhaps our modern word
molecules would more correctly represent what Eeis spoke of
as atoms) of the rod or needle were pushed asunder from one
another in the act of magnetisation, and that on the cessation
of the magnetising influence of the current, these same atoms
strove to return to their previous position of equilibrium,
and thus the oscillations of the atoms led to the vibration of
the needle as a whole. Whether all Eeis's speculations as to
the behaviour of the atoms under varying degrees of magnetis-
ing force are justified in the present aspect of science or not,
is, however, not of any great importance ; the important point
is, that, whether his theory be right or wrong, the instrument
he devised will perform the function he assigned to it : it
will reproduce speech, not loudly, but in reality far more
articulately than many of the telephonic receivers in use
under the names of Bell, Gower-Bell, &c.

One very curious point in connection with this " knitting-
needle" receiver of Eeis, is its extremely bad acoustical
arrangements. It was laid horizontally upon a small sound-
ing-box covered by a lid. If the end of the needle had been
made to press on the resonant-board (as indeed appears to
have been done at first with the violin, p. 29) the vibrations

156 PHILIPP REIS,

would have been much more directly reinforced. But when
merely supported by two wooden bridges the direct com-
munication was largely lost. The pressure of the lid down-
wards upon the spiral, as recommended by Eeis, is no doubt
an important matter acoustically. It is strange that a man
who had grappled in so masterly a way with the acoustical
problem of the transmitter, and had solved it by constructing
that transmitter on the lines of the human ear, should not
have followed out to the same extent those very same
principles in the construction of his receiver. An extended
surface he did employ, in the shape of a sounding-board ; but
it was not applied in the very best manner in this instru-
ment.

The second principle applied by Eeis in the construction
of his telephone-receivers, was that of the electro-magnet.
He arranged an electro-magnet so that the fluctuating
currents passing round the coils set up corresponding
variations in the degree of force with which it attracted its
armature of iron, and so forced the latter to execute corre-
sponding mechanical vibrations. This principle is common
both to the receiver of Eeis, and to the later receivers of
Yeates, Bell, and Edison. Eeis's armature was an iron bar
of oval section ; Yeates's an iron strip screwed to a sound-
board, Bell's was an iron plate, and Edison's an iron plate
also.

For the better comparison of Eeis's electro-magnetic
receiver with those of more modern date, we here present in
Eig. 46 a comparative view of a number of different forms of
receiver in which Eeis's principle of causing an electro-
magnet to set up vibrations in an armature is applied. In
this set of figures, A and B are the suggested forms mentioned
in the letter of Mr. Horkheimer, p. 119, and show an electro-
magnet, opposite the poles of which is placed an armature
(a bar) which must be of iron or other metal capable of
having magnetism induced in it, and which, by reason of its
attachment to an elastic spring, is capable of being made to
oscillate to and fro when attracted with a varying force.
Eeis clearly recognised the necessity of further providing a

INVENTOR OF THE TELEPHONE.

157

sufficient resounding surface by means of which the surround-
ing air could be set in motion ; for in the case of these two
suggestions the electro-magnet and its elastically-mounted
armature were placed within a cigar box. C is a plan of the

receiving instrument previously described and figured in
Plate II. and in figures 21 and 34 on pages 32 and 109.
In this instrument the electro-magnet was horizontal, the
armature, a bar of iron of oval section (which in the original

158 PHILIPP EEIS,

drawing in plate II. appears to have been in reality a hollow
bar or tube) attached to a thin lever described as a plank,
pivoted like a pendulum to an upright support, but prevented
by a set-screw and a controlling spring from vibrating in the
manner of a pendulum. Such an arrangement, in fact,
vibrates in perfect correspondence with any vibrations that
may be forced upon it by the electro-magnet. The broad
flat surface of the lever — he specially directed that it should
be broad and light — transfers the vibrations to the air, and
is aided by the surface of the sounding-board on which the
apparatus stands. This apparatus has, therefore, all the
elements of a successful receiver, except only that its shape
renders it inconvenient for portability. But by reason, firstly
of its armature of iron, secondly of the elastic mounting of
that armature, thirdly of the extended surface presented, it is
admirably adapted to serve as an instrument for reproducing
speech.

Fig. 46 D represents the excellent electro-magnetic receiver
devised in 1865 by Yeates (compare Fig. 42, p. 128) to work
with the Eeis transmitter, and is in many respects identical
with the preceding form. The armature, a strip of iron, was
attached at one end by a very stiff steel spring to a pine-
wood sounding-board over a hollow box, from the- base of
which rose the metal pillar which supported the electro-
magnet. This receiver also contains all the elements of a
successful receiver, the armature being of a material capable
of inductive action, and elastically supported ; whilst the
sound-box provided adequate surface to communicate the
vibrations to the air.

We now come to the more modern instruments of Gray,
Bell, and Edison. So far the receivers of Eeis and of Yeates
were intended for reproducing any sound ; but now for the
first time, ten years after the date of these early telephonic
receivers, we meet with instruments devised with the express
purpose of receiving only certain selected tones.

For the purposes of multiple acoustic telegraphy, that is to
say for the purpose of signalling the " dots " and " dashes "
of the Morse code in a number of different fixed musical

INVENTOR OF THE TELEPHONE. 159

notes, each of which is to be signalled out and repeated by a
receiver adapted to vibrate in that note alone, it is clear that
the instruments of Eeis, adapted as they were to transmit
and receive any sound that a human ear can hear, would not
answer. Accordingly those experimenters, who from about
the year 18*73 to the year 1876, applied themselves to
multiple telegraphy — foremost amongst them being Mr.
Elisha Gray and Prof. Graham Bell — dropped the use of the
tympanum in the transmitter and devised new transmitters
and new receivers, in most of which the ruling idea was that
of employing a vibrating tongue or reed, tuned up to one
particular note. Now it is obvious that a receiver which,
like those of Eeis, is adapted to receive any tone, can also
receive a musical note. But for the operation of " selective "
reception, a receiver must be employed, not only tuned to
one note, but tuned to the very note emitted by the particular
transmitter with which it is to be in correspondence.
Elisha Gray found this out very early in his researches. In
the winter of 1873-4 * he was transmitting musical tones by
a sort of tuning-fork interruptor, and received them on an
instrument shown in Fig. 46 E, which represents a form of
electro-magnet mounted for the purpose. It was " a common
electro-magnet, having a bar of iron rigidly fixed at one pole,
which extends across the other pole, but does not touch it by
about one sixty-fourth part of an inch. In the middle of
this armature a short post is fastened, and the whole is
mounted on a box made of thin pine, with openings for
acoustic effects." It was, in fact, very similar to Yeates's
receiver just described, and Gray found it capable of receiv-
ing not only simple musical tones but composite tones, and
even harmonies and discords. In fact, like Eeis's and
Yeates's receivers, it could receive anything that the trans-
mitter sent to it, even including speech. Now this did not
suit Gray, who wished to have selective receivers, one to take
up note A, another note C, &c. Accordingly in 1876 we find
Gray taking out a fresh patent f for selective receivers, which

* See Prescott's < Speaking Telephone,' p. 158.

f ' British Patent,' No. 1874, of the year 1876 (dated 4th May).

160 PHILIPP REIS,

he also called harmonic analysers, each of which consisted of
" a tuned bar or reed suitably attached to an electro-magnet,
and the whole mounted upon a resonant box." Fig. 46 F is
reproduced from Gray's British patent. " A vibrating tongue
reed, or bar "of steel "is united with one pole of the magnet.
The free end of the reed passes close to, but does not touch
the other pole of the magnet." Gray further says that the
reed is made with parallel sides and tuned by cutting it
away at one point, as this mode prevents false nodal vibra-
tions from occurring.

Selective receivers for multiple telegraphy were also
invented by Graham Bell. The form shown in Fig. 46 / is
transcribed from Fig. 15 of Bell's Specification to his British
Patent, No. 4765, of the year 1876 (dated 9th December),
which the inventor thus describes : " It is preferable to
employ for this purpose an electro-magnet E, Fig. 15, having
a coil upon only one of its legs. A steel spring armature A
is firmly clamped by one extremity to the uncovered leg h of
the magnet, and its free end is allowed to project above the
pole of the covered leg." In fact the arrangement was
almost identical with, but not quite as good mechanically as
that patented seven months previously by Gray. The in-
ventor further said that a number of these instruments
might be placed on one circuit, and that if one of them
were set in vibration, only those would respond which were
in unison with its note ; and further that " the duration of
the sound may be used to indicate the dot or dash of
the Morse alphabet, and thus a telegraphic despatch may
be indicated by alternately interrupting and renewing the
sound."

Anything more totally different from Reis's telephone
than these selective harmonic telegraphs with their tuned
tongues can hardly be imagined. Reis was not aiming at
selective harmonic telegraphy ; he wanted his one instrument
to transmit every sound that a human ear could hear. He
did not dream of using a tuned bar or reed ; his typical
structure was the tympanum of the ear. In fact, as we have
seen above, the tuned reed or tongue was introduced into

INVENTOR OF THE TELEPHONE. 161

telegraphy for the purpose of transmitting single selected
notes to the exclusion of all others.

Strange though it may seem, a tongue receiver like those
of Graham Bell and of Gray just described can be used for
receiving speech ! It is true, as Gray remarks, that a thick
bar of steel, cut away as described, is best adapted for its own
tone only. But Bell's thin steel tongue, though it has its
own fundamental note (and so has every tympanum, for that
matter) when left free to vibrate in its own time, will re-
produce any other note or sound that may be forced upon it
by the varying attraction of the electro-magnet. There is,
indeed, the whole difference between " free " and " forced "
vibrations. One of the strangest delusions that has somehow
grown up in recent telephonic discussions is the almost
incredible proposition that a tongue cannot talk because it is
a tongue. It would be equally veracious to affirm that an
ear (i.e. a tympanum) cannot hear because it is an ear.

But leaving harmonic telegraphy and its " tuned bars,"
both Gray and Bell applied themselves to the old problem of
transmitting human speech. What was their very first step ?
They threw away their " tuned bars " and " steel springs,"
and returned to the tympanum! Elisha Gray devised the
receiver shown in Fig. 46, G, taken from his caveat of date
February 14, 1876.* In that document Gray says : " My
present belief is that the most effective method of providing
an apparatus capable of responding to the various tones of
the human voice, is a tympanum, drum, or diaphragm,"
stretched across one end of a chamber. He adds that in the
receiver there is (see Fig. 46, G) an electro-magnet, acting
upon a diaphragm to which is attached a piece of soft iron,
and which diaphragm is stretched across a vocalising
chamber.

Graham Bell's receiver (the American specification of
which was filed the same day as Gray's caveat) is shown
(in the form patented in Great Britain, Dec. 9, 1876) in
Fig. 46 H, which is taken from Fig. 19 of Bell's British patent.

* Prescott, ' Speaking Telephone,' p. 203.

162 PHILIPP REIS,

" The armature," says the inventor, " is fastened loosely by
one extremity to the uncovered leg, h, of the electro-magnet E,
and its other extremity is attached to the centre of a stretched
membrane." The armature, in fact, was capable of vibrating
like a pendulum on its pivot, but was elastically restrained
by its attachment to the tympanum; the armature would
therefore vibrate in perfect correspondence with any vibra-
tions forced upon it by the electro-magnet. This instrument
as also that of Gray, was admirably adapted to receive speech,
for it embodied the three essential points which Eeis had
already discovered : viz., firstly, that the armature must be of
iron, or capable of being acted upon by magnetic induction ;
secondly, that it must be elastically mounted ; thirdly, that
it should present an extended surface. Bell's form of receiver
had the advantage over Eeis's (compare p. 158), that its
extended surface was a true tympanum of membrane, and
not a mere broad thin plank. Being a tympanum, it there-
fore realised Eeis's fundamental notion of imitating the
human ear more fully than even Eeis's own receiver did.

Figures 46, J, K, and L represent the more recent types of
receiver of Bell and Edison. Fig. 46 J is reproduced from
Fig. 20 of Bell's British Patent, and shows the substitution
of a thin steel plate, attached to a frame, in front of the electro-
magnet, for the membrane and iron armature. This form of in-
strument also embodies Eeis's three principles — but with this
improvement, the armature capable of inductive action, the
elastic mounting, and the extended surface, are here all united
in one organ, the thin flexible tympanum of steel. Apart
from this unification of parts there is absolutely nothing in
this form of Bell's receiver, that Eeis did not invent fourteen
years before. Bell's great and most signal improvement was
not this beautiful mechanical modification of the Eeis
receiver, but lay in the entirely new suggestion to use such a
receiver as a tratismitter to work by magneto-electric induc-
tion. Two of Eeis's receivers (Fig. 21) if coupled up with
a battery will talk together as transmitter and receiver : but
Eeis did not know and never suggested this. Two of Yeates's
receivers (Fig. 42) if coupled up with a battery will talk

INVENTOE OF THE TELEPHONE. 163

together as transmitter and receiver ; but Yeates did not know
and never suggested this. Bell did discover this, and thereby
invented a transmitter which, though now abandoned as a
transmitter, for want of loudness, was more reliable than the
anterior transmitters of Eeis had been. He made another
discovery, presently to bu alluded to — that of putting a
permanent magnet into the transmitter, to enable him to
dispense with the battery ; but beyond this and the other
mechanical simplifications previously mentioned, all that he
discovered may be summed up by saying that he found out
that a receiver constructed on Eeis's principles could work as
a transmitter also. That was Bell's really great and im-
portant discovery which took all the world by storm at the
Centennial Exhibition of 1876.

Bell subsequently added to his claims the substitution of
a permanent magnet with an iron pole-piece, in place of the
simple electro-magnet, thus enabling him to transmit his
fluctuating currents without the trouble of using a battery,
and the Bell transmitter, thus modified, is used to this day as
a receiver. Eeis had in his " knitting-needle " telephone,
employed a permanent magnet of steel to serve as a receiver.
He had not, however, applied it as Bell did to attract a plate
of thin steel.

Fig. 46, K, exhibits a form of electro-magnetic receiver
described in Edison's British Specification, No. 2909, 1877,
Fig. 24. This instrument, though patented seven months
after Bell's instrument, differs from it in no point of im-
portance. Its armature was a thin plate of iron, elastic, and
having an extended surface ; being, in fact, a tympanum.

No one can examine the set of receiving instruments col-
lected in Fig. 46 without being struck with the extraordinary
similarity of design which pervades the entire series. In
every one of the set there is an electro-magnet,. the function
of which is to set an armature * into vibration by attracting it
with a variable force. In every one the armature is of a

* Yet Bell's claim (British Patent Specification) runs: "I claim the
production cf any given sound or sounds from the armature of tho
receiving instrument."

M 2

164 PHILIPP REIS,

material capable of magnetic induction ; that is to say, iron,
steel, or equivalent material. In every one of them the arma-
ture is either elastically mounted, or is in itself elastic. In
every one of them (save only the two quite recent forms, F and
/, which were intended not to speak, but to emit only one fixed
musical note) there is an extended surface (either a sound-
board or a tympanum) to communicate the vibrations to the
air. Lastly, every one of these forms, when connected with
the line through which the telephonic currents are being
transmitted, is perfectly capable of reproducing articulate
speech. But the inventor who had the genius to discover
all these essential points, and to combine them in an instru-
ment, and to use it to reproduce articulate speech, is surely
the true inventor of the system. The inventor of the system
embodying these essential points was Philipp Eeis.

INVENTOR OF THE TELEPHONE. 165

APPENDIX IV.

ON THE DOCTRINE OF UNDULATORY CURRENTS.

"In this Specification the three words 'oscillation? ' vibration? and
1 undulation? are used synonymously." — Graham Bell, U.S. Patent,
No. 174, 465, filed Feb. 14, 1876.

IN the preceding appendices it has been demonstrated that
all that is essential in both transmitter and receiver of a
Telephonic system was to be found existing in 1863 in the
Telephone of Eeis. There yet remains to be met the doc-
trinaire objection that as Eeis never explicitly mentions an
undulatory current as distinguished from an intermittent
one, he never intended to use such a current. This objection
is advanced only by those persons who have committed
themselves to the idea that speech cannot be transmitted by
a transmitter which opens and closes the circuit.

It is certain that Eeis did not in any of his writings ex-
plicitly name an undulatory current : but it is equally
certain that, whether he mentioned it or not, he both used
one and intended to use one. He did not concern himself
as to the precise manner in which the current fluctuated
provided only he attained the end in view — namely, that the
vibrations of the armature of the receiver should be similar
to those of the transmitter. This he did lay down with great
clearness and emphasis as his g aiding principle ; and he cared
not about the intermediate question as to how the current did
the work. He told the world that the electromagnet at the
receiving end must be magnetised and demagnetised corre-
spondingly with the vibrations imparted by the air to the

166 PHILIPP REIS,

tympanum of his transmitter, in order that the armature
might be set into vibrations similar to those of the speaker's
voice. If the tympanum of the transmitter vibrated or
oscillated or undulated — the terms are synonymous — so must
the armature of the receiver. Graham Bell has told us pre-
cisely the same thing : " The current traversing the coils of
the electromagnet E occasions an increase and diminution in
its intensity " [that is to say, magnetises and demagnetises
it], " and the armature A1 is thrown into vibration "...
" and thus imparts to the air at n1 a facsimile copy of the
motion of the air that acted upon the membrane n" Bell
agrees then absolutely in every detail with what Eeis said
on this point. That sound-waves should be transmitted by
a Telephone requires indeed a process of several stages.
(1.) The sound-waves must strike upon the tympanum of
the transmitter and make it undulate, or, oscillate, or vibrate
— whichever term you please — in a corresponding manner.
(2.) The undulating tympanum must act upon the circuit,
and either itself induce undulating or vibrating currents
(Bell's plan, by magnetic induction), or else throw a current
already flowing there, into undulations, or vibrations, or
oscillations (Eeis's plan, by varying contact-resistance), but
in either case these undulations of the current must corre-
spond to the original undulations of the air-waves. (3.) The
undulating, or vibrating, or oscillating current must run
round the coils of the electromagnet and cause its magnetic
force to undulate, or oscillate, or vibrate by demagnetising
it and then magnetising it, but this also must be in a manner
corresponding to the original undulations. (4.) Further, the
armature of the receiver must be set into undulations, or
vibrations, or oscillations corresponding to those of the force
of the electromagnet, and therefore to the undulations of the
current that is magnetising and demagnetising it, and there-
fore identically corresponding with the original undulations
of the sound-waves. (5.) The armature must communicate its
vibrations to the air and to the ear of the listener. Of these
successive stages Eeis explicitly told the world that his instru-
ment was to do the first one and the last three, and he several

INVENTOR OF THE TELEPHONE. 167

times emphasized the statement, that the final undulations of
the last stage were to be similar to the original undulations
of the first stage. The air at the listening end, the armature
of the receiver, and the magnetism of the magnet, were all
to be set by the fluctuations of the current into undulations
corresponding with those of the tympanum at the speaker's
end, and of the waves of his voice. It is perfectly clear
therefore, that he regarded as self-evident the intermediate
stage, and he did not dwell upon the necessity of the point,
that his transmitting-current must also vibrate, because this
was obviously so, and was only an intermediate matter of
secondary moment. He chose rather to point out the ne-
cessity of unification between the first and last stages, leaving
it to common sense to see that the " interruption " or the
" opening and closing " of the circuit must be effected in a
manner corresponding to the undulations of the impressed
sound-wave. Had the " interruptions " not been of the nature
of corresponding variations of contact, the current could not
have been set into corresponding vibrations, and the armature
of the electromagnet could not have reproduced the vibrations
of the transmitter. Clearly Eeis's whole conception of tele-
phony included as a minor and intermediate step the fact
that the current was, by the action of the transmitter, caused
to vary in strength in correspondence with the undulations
of the tympanum — that, in fact, it was made to undulate
by the action of the tympanum and of the interrupter which
opened and closed the circuit in obedience to the undulations
of the tympanum and in proportion to them.

A difficulty has been raised by telegraph operators that
opening and closing the circuit means opening and closing
the circuit in abrupt alternations of make-and-break. Eeis
never said so. Reis never used the phrase in this restricted
and technical sense. He was not a professional telegraphist,
and, as pointed out in Appendix L, he so arranged his contacts
with the following springs and other contrivances, that the
" opening and closing " of the circuit should not and could
not be abrupt. A Reis transmitter is no more a " make-and-
break " instrument than the Blake transmitter is. Both will

168 PHILIPP EEIS,

give undulatory currents by opening and closing the circuit
to a greater or less degree, if spoken gently to. Both will
give abrupt makes-and-breaks of the circuit if shouted to, in
spite of the following-springs, which are used to prevent abrupt
interruptions. The term " opening and closing " which Eeis
applied to his transmitter, is used by him in exactly the same
way as the phrase is used by engineers in describing the
action of the governing throttle-valve of a steam-engine. The
function of the governor, we are told in treatises on en-
gineering, is to open and close the throttle-valve in a manner
corresponding to the fall or rise of the governor-balls. No
one in his senses imagines that the opening and closing action
here referred to means an absolutely abrupt intermitteiice in
the supply of steam. If the governor-balls rise a little by
increase of speed, there is a corresponding closing, propor-
tionate in amount to the amount of rise. If any person were
to impress an oscillatory motion of rise and fall upon the
governor, the supply of steam would be thrown into corre-
sponding undulations. The matter stands precisely so with
Eeis's " interrupter " or " regulator ; " it opens and closes the
circuit in a manner corresponding with the undulations com-
municated to it. If it did not, it would violate the principle
of correspondence so emphatically laid down by Eeis,

It is, however, true that Eeis's instruments, in spite of
springs and adjusting screws, and other devices to prevent
abrupt make-and-break occurring, were prone, by reason of
the very lightness of the parts, to break contact, if too loudly
spoken to. They share this fault with the more perfect
transmitters of Blake and Berliner which are used to-day so
generally. The undulatory currents of these transmitters are,
like those of Eeis's transmitters, liable to an occasional abrupt
interruption, which, though it may not seriously affect the
intelligibility of the words, does, to some extent, mar the
perfection of the articulation. Still, in practice, to judge
by the instruments used in the telephone exchanges of Great
Britain, the Blake transmitter with its liability to make-and-
brake abruptly is a more satisfactory instrument than the Bell
transmitter, which is not used at all. Now the Bell trans-

INVENTOR OF THE TELEPHONE. 169

mitter working on the principle of which Bell is the first and
undisputed inventor, is one in which the degree of contact in
the circuit is never changed : for it works by the principle of
" induction," whereby currents are set up in a circuit that is
never opened or closed, either partially or wholly. Never-
theless the Blake transmitter, which opens and closes the cir-
cuit in proportion to the undulations of the tympanum, is the
more satisfactory instrument for producing the undulating
currents required to procure the all-essential correspondence
between the undulations of the tympanum of the transmitter
and those of the armature of the receiver. To sum the matter
up, it appears that an instrument which opens and closes the
circuit on Eeis's principle of transmitting is in practice a more
satisfactory transmitter of undulatory currents than Bell's
transmitter which cannot open or close the circuit in the
least. Eeis, with his instruments, transmitted speech — as
Herr Hold tells us (p. 126) — when the words spoken were not
too loud. That is a proof that he did really use, whether he
knew it or not, undulatory currents of electricity : and an
undulatory current is none the less an undulatory current,
even if occasionally abruptly interrupted. A speech is none
the less a speech, even if the orator sneeze once or twice while
speaking. Nay, we may go further, and say that an undu-
latory current is an undulatory current, even though the
finer ripples of the waves are lost in transmission. This is
what seems to have been the case with Eeis's instruments as
they were in 1861 and 1862. The consonants were satisfac-
torily transmitted, and so were all musical tones within the
range of the instrument. But the finer ripples of the vowels
were lost somehow in transmission. Eeis, whose innate
honour and modesty led him always rather to understate than
overstate the facts, most frankly acknowledged this, nay even
invited attention to the fact, and discussed the imperfection
from a high scientific standpoint. He proposed to rely for the
correctness of his views upon the actual recorded curves of
sound-waves, as taken down automatically by the then
newly-invented phonautograph of Scott (see p. 60). It is
perfectly marvellous how precise his views were upon the

170 PHILIPP JREIS,

correspondence between the graphic curve or wave-form
of a sound and the actual sound itself; a precision amply
justified by the experience and the discoveries of the last
ten years.

This matter of representing sounds — or rather the varying
density of the air in the sound-wave — by a graphic curve,
was a vital one to Reis. Had he had a less clear view of the
nature of sound-waves than that afforded by a graphic curve,
I doubt whether he would ever have grasped the problem of
the telephone — that the final vibrations, or undulations, or
oscillations of the armature in the receiver must correspond
with — must be the very counterpart of — those of the tym-
panum of the transmitter. The clearness with which Eeis
saw this is only surpassed by the clearness with which he
expressed himself upon it. For him a sound was simply a
complicated series of variations in the density of the air, and
capable, in all its complexity, of being represented by the
rise and fall of an undulatory curve. " Every tone, and every
combination of tones, evokes in our ear vibrations . . . the
motions of which may be represented by a curve" (p. 54).
" That which is perceived by the auditory nerve . . . may be
represented graphically according to its duration and magnitude
by a curve "... (p. 53). " Our ear can perceive absolutely
nothing more than is capable of being represented by similar
curves " (p. 53). The curves with which he accompanied
his original memoir — and now reproduced in facsimile, from
Legat's plates, at the end of this volume — are evidence of
the thoroughness of his grasp on the undulatory principle.
And he explicitly states this principle amongst " the various
requisite conditions which must be fulfilled by the trans-
mitting and receiving apparatus for the solution of the problem
that has been set " (Legat's Report, p. 71). He declared
that so soon as it should become possible " at any place,
and in any prescribed manner " (that is to say, whether by
electric undulations or by mechanical undulations, as in
the string of the toy telephone, or by any other ineans), " to
set up vibrations whose curves are like those of any given
tone or combination of tones," we should then receive the

INVENTOR OF THE TELEPHONE.

171

same impression as that tone or combination of tones would
have produced upon us.

So much for Eeis's principle of correspondence of undula-
tions between the transmitter and the receiver ; we have seen
how clear and precise, yet how comprehensive it was, and how
the general proposition necessarily included within itself, as
an intermediate step, the particular minor proposition that the
undulations of the current must also be in correspondence
with the voice.

Keeping these points in mind, it is very remarkable that
when Graham Bell, fourteen years later, followed Eeis " into
the field of telephonic research," he selected the very same
method of expressing the relations between sounds and the
undulations which corresponded with them. To show how
remarkably in agreement the views of Eeis and Bell are upon
this question of representing by a curve the undulations
which correspond to the voice, we select the following para-
graphs and place them in parallel columns.

Eeis.

That which is perceived by
the auditory nerve . . . may
be represented graphically,
according to its duration and
magnitude by a curve. — (Me-
moir ' On Telephony ' in the
Jahresbericht of the Physical
Society of Frankfurt - a. - M.
1860-61, p. 59.) [p. 53.]

The height or depth of
the sound produced . . .
depends upon the number of
vibrations made in a given
time.— (lb. p. 63.) [p. 59.]

The greater the condensa-
tion of the sound-conducting

Bell.

Electrical undulations, in-
duced by a body capable of
inductive action, can be repre-
sented graphically, without
error by the same sinusoidal
curve which expresses the vi-
bration of the inducing body
itself, and the effect of its vi-
bration upon the air ; for, as
stated above, the rate of oscilla-
tion in the electrical current
corresponds to the rate of vi-
bration of the inducing body
— that is, to the pitch of the
sound produced.— (Specifi-
cation of U. S. Patent No.
174,465, dated March 7, 1876.)

The intensity of the current
varies with the amplitude of

172

PHILIPP REIS,

Eeis.

medium at any given moment,
the greater will be the ampli-
tude of vibration of the mem-
brane.—(16. p, 58.) [p. 52.]
. . . each tone is dependent
not only on the number of
vibrations of the medium, but
also on the condensation or
rarefaction of the same. —
(Legat's Report, Zeitschrift des
D.-Oesterr. Telegr. Yereins,
1863, p. 125.) [p. 77.]

Let us exhibit the condensa-
tion curves for three tones —
each singly (Plate I) : then,
by adding together the ordi-
nates corresponding to equal
abscissae, we can determine
new ordinates and develop a
new curve which we may call
the combination-curve. Now
this gives us just exactly what
our ear perceives from the
three simultaneous tones.
— (Memoir ' On Telephony,'
p. 59.) [p. 54.]

Bell

the vibration — that is, with
the loudness of the sound ; —

and the polarity of the current
corresponds to the direction of
the vibrating body, — that is,
to the condensations and
rarefactions of air produced
by the vibration. — (76.)

The combined effect of A
and B, when induced simul-
taneously on the same circuit,
is expressed by the curve
A -f B, Fig. 4, which is the
algebraical sum of the sinu-
soidal curves A and B. This
curve A + B also indicates the
actual motion of the air when
two musical notss con-
sidered are sounded simul-
taneously. . . . (16.)- The
electrical movement, like the
aerial motion, can be repre-
sented by a sinusoidal curve, or
by the resultant of several
sinusoidal curves. — (J6.)

The very remarkable agreement of the preceding passages
receives a most striking confirmation by comparing the
curves respectively drawn by Eeis and by Bell. These are
facsimiled below, Keis's " combination "-curve (Fig. 47) from
Plate I. of his Memoir (also Plate I. of this volume), and
Bell's " resultant "-curve (Fig. 48) from Fig. 4 of his United
States Patent Specification No. 174,465.

The most casual observer cannot fail to notice here that
the three lines of undulatory curves of Bell's specification

INVENTOR OF THE TELEPHONE.

173

are practically identical with the three lower lines of undu-
latory curves of Eeis's memoir. They are, moreover, in each
case introduced for the sake of showing how a complex curve
corresponds to a compound undulation.

Eeis.

A..

Fig. 48.

Far be it from me even to hint that either curve was
plagiarised from the other. Bell tells us that his curve is to
represent electrical oscillations, which, he adds, have the
same curve as that both of the vibrating body and of the air.
Eeis tells us that his curve is to represent the oscillations of
a tympanum, or of the air, or of the magnetisation of the
magnet, or of the armature at the receiving end. How the
magnetization of the electro-magnet was made to vary " cor-
respondingly with the condensations and rarefactions of the
air," as represented by such a curve, Eeis did not explicitly
say, but left to the common sense of his readers to infer.
Though the inference was obvious, Bell, who possibly had not

174 PHILIPP REIS,

then read Reis's researches, seized upon this intermediate
stage of the process employed by Eeis, and probably quite
unconscious that Reis had already employed it, announced it
as a discovery of his own ; and then, losing sight of the point
that all that was wanted was to secure correspondence
between the initial and final stage, he magnified to an absurd
and unwarranted importance this intermediate correspond-
ence of the vibrations of the current with those of the tym-
panum, which correspondence any one reading Reis's papers
would know at once Reis had implicitly assumed and actually
employed when he transmitted articulate speech.

If we pass from the method of graphically representing
undulations by curves, and proceed to compare the language
in which Reis described the action of his machine in re-
producing the undulations imparted to the transmitter, with
that in which Graham Bell described the action of his
machine some fourteen years later, we shall find * an agree-
ment even more precise.

* In making these comparisons in parallel columns, I wish to repudiate
in the most emphatic way any sinister inference that might be drawn as
to Graham Bell's use of descriptions and curves identical in so many
points with those of Reis. For, in the first place, I believe Professor Bell
to be incapable of such contemptible appropriations, and the candour with
which he has himself invited comparison by giving various references to
Eeis's papers, itself precludes such inference. In the second place, I do
not think that at the date of these quotations Bell understood German
sufficiently well to comprehend Reis's very precise statement of the
problem of the Telephone. I simply exhibit these parallel extracts to
show the thoroughness with which Reis had grappled with the problem
with which, fourteen years later, Bell also grappled ; and to prove in the
most irrefragable manner, from the necessary identity in the terms
selected for expressing the facts of the solution of the problem, that the
problem to which each found a solution was identical. The circumstance
that does, however, puzzle me, and which does not appear in these
parallel extracts, is that, whilst in his original memoir, Reis speaks in
detail of the auditory ossicles and their movements as having suggested
his transmitter, and casually mentions the phonautograph of Scott in
support of his views, Bell, in his original lecture before the American
Academy, speaks in detail of Scott's phonautograph as having suggested
his transmitter, and casually refers to the auditory ossicles and their
movements.

INVENTOR OF THE TELEPHONE.

175

Eeis.

The electromagnet . . .
will be demagnetised and mag-
netised correspondingly with
the condensations and rarefac-
tions of the mass of air, . . . and
the armature . . . will be
set into vibrations similar to
those of the membrane in
the transmitting apparatus. —
(Legat's Report, Zeitschrift,
p. 128, 1862.) [p. 77.]

The transmitter, Fig. A,
consists of a conical tube . . .
closed by a membrane ... by
speaking . . . into the tube . . .
there will be evoked a motion
of the membrane. . . (op. tit.)

The apparatus . . . offers
the possibility of creating
these vibrations in every
fashion that may be desired,
and the employment of electro-
galvanism gives us the possi-
bility of calling into life, at
any given distance, vibrations
similar to the vibrations
that have been produced, and
in this way to reproduce at any
place the tones that have been
originated at another place. —
(Legat's Eeport, op. cit.)

As soon therefore as it shall
be possible ... to set up
vibrations whose curves are
like those of any given tone or

Bell

The current traversing the
coils of the electromagnet E,
occasions an increase and dimi-
nution in its intensity, and the
armature A1 is thrown into
vibrations . . . and thus im-
parts to the air at n1 a fac-
simile copy of the motion of
the air that acted upon the
membrane n. — (Specification
of British Patent, No. 4765,
Dec. 9th, 1876, p. 17.)

A cone A is used to con-
verge sound vibrations upon
the membrane.

When a sound is uttered in
the cone the membrane a is
set in vibration. . . .

. . . and thus electrical undu-
lations are created upon the
circuit E b e f g. . . . The
undulatory current passing
through the electromagnet /
influences its armature h to
copy the motion of the arma-
ture c. . . . These undula-
tions are similar in form
to the air undulations
caused by the sound.

— that is, they are repre-
sented graphically by similar
curves. .

176

PHILIPP REIS,

Eels.

combination of tones, we shall
receive the same impression
as that tone or combination of
tones would have produced
upon us. — (Memoir * On Tele-
phony,' p. 60.) [p. 55.]

Any sound will be repro-
duced, if strong enough to set
the membrane in motion. —
(Letter to Mr. Ladd, 1863.)
[P- 84.]

the armature belonging to
the magnet will be set into
vibrations similar to those
of the membrane in the
transmitting apparatus.—
(Legat's Eeport, 1862.) [p. 77.]

Bell

A similar sound to that
uttered into A is then heard to
proceed from I. — (Specification
of U. S. Patent, No. 174,465.)

There are many other uses
to which these instruments
may be put, such as ... the
telegraphic transmission of
noises or sounds of any
kind.— (16.)

I would have it understood
that what I claim is : — . . .
. . . Tenth. In a system of
electric telegraph or telephony
consisting of transmitting and
receiving instruments united
upon an electric circuit, I claim
the production in the armature
of each receiving instrument
of any given motion by subject-
ing said armature to an attrac-
tion varying in intensity, how-
ever such variation may be
produced in the magnet, and
hence I claim the produc-
tion of any given sound or
sounds from the armature
of the receiving instru-
ment by subjecting said arma-
ture to an attraction varying
in intensity in such manner
as to throw the armature
into that form of vibration
that characterizes the
given sound or sounds. —
(Specification of British Pa-
tent, No. 4765, Dec. 9, 1876.)

INVENTOR OF THE TELEPHONE. Ill

One cannot help thinking that some claims to great inven-
tions are just a little " too previous."

If it should still be said that Eeis's method of transmitting
speech, whether it did its work by undulatory currents or no,
was avowedly imperfect, and that therefore such a claim as
that quoted above is justified by the subsequent invention of
an instrument the articulation of which was more reliable, let
us compare what each inventor has said about the imper-
fections* of his own instrument.

Reis. Bell.

That which has here been It is a mistake, however, to
spoken of will still require suppose that the articulation
considerable improvement, was by any means perfect. . . .
and in particular mechanical Still the articulation was there,
science must complete the and I recognized the fact that
apparatus to be used. — (Legat's the indistinctness was entirely
Report, 1862.) [p. 78.] due to the imperfection of the

instrument. — (' Kesearches in
Telephony,' Journal of Soc. of
Telegr. Engineers, Dec. 1877.)

If it should be said that Bell is here speaking only of an
early and experimental form, and not of his real invention,
it should be remembered that Bell here refers to the appa-
ratus with cone and membrane, identical with that exhibited
at Glasgow in September, 1876, by Sir William Thomson
(who had received it from Bell) and by him described as
the very " hardihood of invention," and " by far the greatest
of all the marvels of the electric telegraph." It certainly

* Reis's failures were chiefly with the vowels, Bell's more particularly
with the consonants. Reis's contacts were liable to break, and the follow-
ing-springs of his contact-regulators too little pliable. Bell's transmitter
could not open and close the circuit proportionally with the motions of the
tympanum, and owing to the sluggishness due to self-induction in the coils
of his telephone, the induced undulations of the current failed to come up
in suddenness to those of the tympanum. In consequence whip sounded
like whim, and kiss like kith, even in the perfected Bell Telephones made
two years after Bell's first " improvements " in telephony were patented.

178 PHILIPP REIS,

worked upon the principle of undulatory currents,* whether it
articulated or not. Bell had himself, speaking in May 1876,
before the American Academy of Arts and Sciences upon his
researches, even more explicitly admitted the imperfections of
his own instrument.

The effects were not suffi-
ciently distinct to admit of
sustained conversation through
the wire. Indeed, as a general
rule, the articulation was
unintelligible, excepting
when familiar sentences were
employed. — (Proceedings of
American Academy of Arts
and Sciences, vol. xii. p. 7.)

Yet this most imperfect machine, of which the articulation
was, as a general rule, unintelligible, had, two months pre-
viously, had a patent granted to it as a new invention, the
claim being for " the method of, and apparatus for, trans-
mitting vocal or other sounds telegraphically, as herein

* The following very remarkable passage occurs in the evidence given
by Professor Graham Bell concerning Keis'.s Telephones. (See published
volume of ' Proceedings in the United States Patent Office before the
Commissioner of Patents/ Evidence for A. G. Bell, p. 14.)

Question 37. "If a Reis Telephone, made in accordance with the
descriptions published before the earliest dates of your invention, would in
use transmit and receive articulate speech as perfectly as the instruments
did which were used by you on June 25, 1876, at the Centennial, would
it be proof to you that such Reis Telephones operated by the use of un-
dulatory movements of electricity in substantially the same way as your
instruments did upon the occasion referred to ? "

Answer by Bell. " The supposition contained in the question cannot
be supposed. Were the question put that if I were to hear an instrument
give forth articulate speech transmitted electrically as perfectly as my
instruments did on the occasion referred to in the question, I would hold
this as proof that the instrument had been operated by undulatory
movements of electricity, I would unhesitatingly answer, Yes."

Surely no better authority is needed to support the proposition that if
Reis made his Telephone speak, as he said he did, he employed undulatory
currents.

INVENTOR OF THE TELEPHONE. 179

described, by causing electrical undulations similar in form to
the vibrations of the air accompanying the said vocal or other
sounds, substantially as set forth."

If then mere mechanical imperfections do not make an
invention any the less a true invention capable of legal recog-
nition, it would be dishonest to the last degree to deny to
Philipp Eeis the honour of his invention, of which he honestly
and openly stated both the successes and the imperfections.
He told the world what he aimed at, and in what measure
success had crowned his aims. His claim to be the inventor
of the Telephone he considered to be justified by that measure
of success. If he was so far in advance of his time that the
world was unprepared to receive or use the splendid discovery
which he gave freely to it, that was not his fault ; nor does
neglect or apathy make him in one single degree the less en-
titled to the credit of his inventions. Tulit alter Jionores has
not unfrequently been truly said concerning the men of
genius who have had the misfortune to live in advance of
the age.

But posterity does not let the names of such truly great
ones perish in the dust. The inventor of the Telephone will
be remembered and honoured in the coming if not in the
present age.

180

PHILIPP REIS,

SCHEDULE OF AUTHORITIES

Title of Work.

Place of
Issue.

Date.

Volume and
Page.

British
Museum.

' Jahresbericht des Phy-1
sikalischen Vereins zu>
Frankfurt-am-Main ' . . j

Frankfurt-
a.-M.

(1860-1
\1863

p. 57 \
p. 129 /

Ac. 4428

' Fortsohritte der Physik "1
(Kronig and Beetz) . . /

Berlin ..

/1861
\1863

xvii. p. 171-173.. \

?p. 96.. ../

Ac. 3775

Dingler's ' Polytechnisches I
Journal* j

Stuttgart

1863

(clxviii. p. 185-187)
'clxix. p. 23.. ..}
|clxix. p. 399 .. )

Pp. 1780

* Polytechnisches Central-
Blatt ' (Schnedermann
and Botteher)

Cassel ..

1863

xxix. p. 858

Pp. 1615 6.

Bottger's ' Polytechni-1
sches Notizblatt ' . . . . J

Mainz

1863

/No. 6 \
\No.l5 .. ../

Pp. 1787

' Didaskalia ' 1

Frankfurt- \
a.-M. J

1862

May 8, May 14 ..

••

'Zeitschrift des Deutsch-
Oesterreichischen
Telegraphen Vereins ' {
(Dr. Brix) J

Berlin . .

1862

ix. p. 125 .. ..

Kuhn's * Handbuch der
angewandten Elektrici-
tatslehre'

Leipzig . .

1866

p. 1017-1021 ..

2244i ..

Pisko's ' Die Neueren Ap-^l
parate der Akustik ' . . /

Vienna . .

1865

/p. 94-103 .. ..}
\p. 241-243 .. ../

8705 cc.

(Pisko's) 'Hessler's Lebr-
bucb der Tecbniscben
Physik'

Vienna . .

1866

Vol. I. p. 648 ..

••

Miiller Pouillet's «Lebr-|
buch der Physik'

Brunswick

1868

Vol. II. p. 386-388

••

INVENTOR OF TEE TELEPHONE.

181

AND KEFERENCES.

Royal Society.

Ronald's Library.

Institution Civil 1
Engineers.

Royal Institution.

Great Seal Patent
Office.

School of Mines.

University College,
London.

Bodleian Library,
Oxford.

King's College.

Oxford University I
Museum Library.!

1846-1860

••

-•

6546, us E

••

1296, 94 A

••

1132, 94 I

••

9511, 24 E

••

13146, 163 c

••

198 e 133

••

• •

'•

••

• •

••

IA newer 1
edition }
(1872) 1

••

(Ed.

1876)

• •

182 PHILIPP REIS.

ADDITIONAL REFERENCES CONCERNING REIS'S
TELEPHONE.

Schenk's Philipp Reis, der Er finder des Telepkons, 1878.

Sack's Die Entivickelung der elektrischen Telephonic, 1878.

Ferguson's Electricity (Ed. 1867), p. 257.

Wiedemann's Galvanismus (1874), Vol. ii. p. 598.

Gartenlaule, die; for 1863, No. 51, p. 807-809.

Am der Natur ; for 1862, xxi. p. 470-474.

Cosmos, Vol. xxiv. p. 349 (1864).

Proc. Lit. Phil. Soc. Manchester (1865), Nov. 10, 1864.

Rep. Brit. Assoc. (1863), p. 19.

Die Geschichte und Entwickelung des elektrischen Fernsprech-

wesens, 1880. (Officially issued from the Imperial German

Post-Office, Berlin.)

LONDON : PRINTED BY WILLIAM CLOWES AND SONS, LIMITED, STAMFORD STREET
AND CHARING CROSS.

Plate.l.

REPRODUCTION OF TONES IN THE ELECTRO-GALVANIC WAY.

THOS KELL A SON, LITH.40.KING ST COVENT GARDEN.

Pb.te.Il.

REPRODUCTION OF TONES IN THE ELECTRO-GALVANIC WAY.

HQ>-€HQ

THOS KELL i SON, LITH. 40. KING ST COVEKT GARDE?:.

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F.R.I.B.A. Third edition, fcap. 8vo, cloth, u. 6d.

Tropical Agriculture ; or, the Culture, Preparation,

Commerce, and Consumption of the Principal Products of the Vegetable
Kingdom, as furnishing Food, Clothing, Medicine, etc., and in their
relation to the Arts and Manufactures ; forming a practical treatise and
Handbook of Reference for the Colonist, Manufacturer, Merchant, and
Consumer, on the Cultivation, Preparation for Shipment, and Commercial
Value, etc., of the various Substances obtained from Trees and Plants
entering into the Husbandry of Tropical and Sub-Tropical Regions. By
P. L. SIMMONDS. Second edition, revised and improved, 515 pages,
8vo, cloth, i/. \s.

Steel: its History, Manufactiire, and Uses. By

J. S. JEANS, Secretary of the Iron and Steel Institute. 860 pages and
•2$ plates, 8vo, cloth, 36^.

American Foundry Practice: Treating of Loam,

Dry Sand, and Green Sand Moulding, and containing a Practical Treatise
upon the Management of Cupolas, and the Melting of Iron. By T. D.
WEST, Practical Iron Moulder and Foundry Foreman. Second edition,
•with numerous illustrations, crown 8vo, cloth, los. 6d.

The Maintenance of Macadamised Roads. By T.

CODRINGTON, M.I.C.E, F.G.S., General Superintendent of County Roads
for South Wales. 8vo, cloth, 6s.

Hydraulic Steam and Hand Power Lifting and

Pressing Machinery. By FREDERICK COLYER, M. Inst. C.E., M. Inst. M.E.
With 1$ plates, 8vo, cloth, i8j.

Pumps and P limping Machinery. By F. COLYER,

M.I.C.E., M.I.M.E. With 23 jolding plates, 8vo, cloth, 12s. 6d.

Tables of the Principal Speeds occurring in Mechanical

Engineering, expressed in metres in a second. By P. KEERAYEFF, Chief
Mechanic of the Obouchoff Steel Works, St. Petersburg ; translated by
SERGIUS KERN, M.E. Fcap. 8vo, sewed, 6d.

Girder Making and the Practice of Bridge Building

in Wrought Iron, illustrated by Examples of Bridges, Piers, and Girder
Work, etc., constructed at the Skerne Iron Works, Darlington, by
EDWARD HUTCHISON, M. Inst. M.E. With 35 plates, demy 8vo,
cloth, los. 6d.

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Spons Dictionary of Engineering, Civil, Mechanical,

Military, and Naval', with technical terms in French, German, Italian,
and Spanish, 3100 pp., and nearly 8000 engravings, in super-royal 8vo,
in 8 divisions, 5/. 8.r. Complete in 3 vols., cloth, 5/. 5^. Bound in a
superior manner, half-morocco, top edge gilt, 3 vols., 6/. I2J.
Seepage 15.

A Treatise on the Origin, Progress, Prevention, and

Cure of Dry Rot in Timber; with Remarks on the Means of Preserving
Wood from Destruction by Sea- Worms, Beetles, Ants, etc. By THOMAS
ALLEN BRITTON, late Surveyor to the Metropolitan Board of Works,
etc., etc. With 10 plates, crown 8vo, cloth, 'js. 6d.

Metrical Tables. By G. L. MOLESWORTH, M.I.C.E.

32mo, cloth, is. 6d.

CONTENTS.

General — Linear Measures — Square Measures — Cubic Measures — Measures of Capacity —
Weights — Combinations — Thermometers.

A Handbook of Electrical Testing. By H. R.

KEMPE, Member of the Society of Telegraph Engineers. New edition,
revised and enlarged, with 81 illustrations. Crown 8vo, cloth, I2s. 6d.

Electro -Telegraphy. By FREDERICK S. BEECHEY,

Telegraph Engineer. A Book for Beginners. Illustrated. Fcap. 8vo,
sewed, 6d.

Handr ailing: by the Square Cut. By JOHN JONES,

Staircase Builder. Fourth edition, with seven plates, 8vo, cloth, 3^. 6d.

Handrailing : by the Square Cut. By JOHN JONES,

Staircase Builder. Part Second, with eight plates, 8vo, cloth, $s. 6d.

The Gas Consumer s Handy Book. By WILLIAM

RICHARDS, C.E. Illustrated. i8mo, sewed, 6d.

Steam Heating for Buildings ; or, Hints to Steam

Fitters, being a description of Steam Heating Apparatus for Warming
and Ventilating Private Houses and large Buildings ; with Remarks on
Steam, Water, and Air in their relation to Heating ; to which are added
miscellaneous Tables. By J. W. BALDWIN, Steam Heating Engineer.
With many illustrations. Second edition, crown 8vo, cloth, ics. 6d.

PUBLISHED BY E. & F. N. SPON.

A Pocket-Book of Useful Formula and Memoranda

for Civil and Mechanical Engineers. By GUILFORD L. MOLESWORTH,
Mem. Inst. C.E., Consulting Engineer to the Government of India for
State Railways. With numerous illustrations, 744 pp. Twenty-first
edition, revised and enlarged, 32mo, roan, 6s.

SYNOPSIS OF CONTENTS:

Surveying, Levelling, etc. — Strength and Weight of Materials — Earthwork, Brickwork,
Masonry, Arches, etc. — Struts, Columns, Beams, and Trusses — Flooring, Roofing, and Roof
Trusses — Girders, Bridges, etc. — Railways and Roads — Hydraulic Formulae — Canals, Sewers,
Waterworks, Docks — Irrigation and Breakwaters — Gas, Ventilation, and Warming — Heat,
Light, Colour, and Sound — Gravity : Centres, Forces, and Powers — Millwork, Teeth of
Wheels, Shafting, etc. — Workshop Recipes — Sundry Machinery — Animal Power — Steam and
the Steam Engine— Water-power, Water-wheels, Turbines, etc. — Wind and Windmills-
Steam Navigation, Ship Building, Tonnage, etc. — Gunnery, Projectiles, etc. — Weights,
Measures, and Money — Trigonometry, Conic Sections, and Curves — Telegraphy— Mensura-
tion—Tables of Areas and Circumference, and Arcs of Circles — Logarithms, Square and
Cube Roots, Powers — Reciprocals, etc. — Useful Numbers — Differential ar.d Integral Calcu-
lus— Algebraic Signs — Telegraphic Construction and Formulas.

Spons Tables and Memoranda for Engineers;

selected and arranged by J. T. HURST, C.E., Author of 'Architectural
Surveyors' Handbook,' ' Hurst's Tredgold's Carpentry, ' etc. Fifth edition,
64010, roan, gilt edges, I s. ; or in cloth case, is. 6d.

This work is printed in a pearl type, and is so small, measuring only 2t in. by if in. by
i in. thick, that it may be easily carried in the waistcoat pocket.

" It is certainly an extremely rare thing for a reviewer to be called upon to notice a volume
measuring but 2$ in. by if in., yet these dimensions faithfully represent the size of the handy
little book before us. The volume — which contains 118 printed pages, besides a few blank
pages for memoranda — is, in fact, a true pocket-book, adapted for being carried in the waist-
coat pocket, and containing a far greater amount and variety of information than most people

would imagine could be compressed into so small a space The little volume has been

compiled with considerable care and judgment, and we can cordially recommend it to our
readers as a useful little pocket companion." — Engineering.

Analysis, Technical Valuation, Purification and Use

of Coal Gas. By the Rev. W. R. BOWPITCH, M.A. With wood engravings,

8vo, cloth, 12s. 6d.

Condensation of Gas — Purification of Gas— Light — Measuring — Place of Testing Gas —
Test Candles — The Standard for Measuring Gas-light — Test Burners — Testing Gas for
Sulphur — Testing Gas for Ammonia — Condensation by Bromine — Gravimetric Method of
taking Specific Gravity of Gas — Carburetting or Naphthalizing Gas — Acetylene — Explosions
of Gas — Gnawing of Gaspipes by Rats — Pressure as related to Public Lighting, etc.

A Practical Treatise on Natural and Artificial

Concrete, its Varieties and Constructive Adaptations. By HENRY REID,
Author of the ' Science and Art of the Manufacture of Portland Cement.'
New Edition, with 59 woodcuts and $ plates, 8vo, cloth, 15^.

Hydrodynamics : Treatise relative to the Testing of

Water- Wheels and Machinery, with various other matters pertaining to
Hydrodynamics. By JAMES EMERSON. With numerous illustrations,
360 pp. Third edition, crown 8vo, cloth, 4.5-. 6d.

CATALOGUE OF SCIENTIFIC BOOKS

The Gas Analyst's Manual. By F. W. HARTLEY,

Assoc. Inst. C.E., etc. With numerous illustrations. Crown 8vo,
cloth, 6s.

Gas Measurement and Gas Meter Testing. By

F. W. HARTLEY. Fourth edition, revised and extended. Illustrated,
crown 8vo, cloth , 4^.

The French- Polisher s Manual. By a French-
Polisher; containing Timber Staining, Washing, Matching, Improving,
Painting, Imitations, Directions for Staining, Sizing, Embodying,
Smoothing, Spirit Varnishing, French- Polishing, Directions for Re-
polishing. Third edition, royal 32ino, sewed, &d.

Hops, their Cultivation, Commerce, and Uses in

various Countries. By P. L. SiMMONDS. Crown 8vo, cloth, 4^. 6d.

A Practical Treatise on the Manufacture and Distri-
bution of Coal Gas. By WILLIAM RICHARDS. Demy 410, with numerous
wood engravings and 29 plates, cloth, 28s.

SYNOPSIS OF CONTENTS :

Introduction — History of Gas Lighting — Chemistry of Gas Manufacture, by Lewis
Thompson, Esq., M.R.C.S. — Coal, with Analyses, by J. Paterson, Lewis Thompson, and
G. R. Hislop; Esqrs. — Retorts, Iron and Clay — Retort Setting — Hydraulic Main — Con-
densers— Exhausters — Washers and Scrubbers — Purifiers — Purification — History of Gas
Holder — Tanks, Brick and Stone, Composite, Concrete, Cast-iron, Compound Annular
Wrpught-iron — Specifications — Gas Holders — Station M eter — Governor — Distribution-
Mains — Gas Mathematics, or Formulae for the Distribution of Gas, by Lewis Thompson, Esq.—
Services — Consumers' Meters — Regulators — Burners — Fittings — Photometer — Carburization
of Gas — Air Gas and Water Gas — Composition of Coal Gas, by Lewis Thompson, Esq. —
Analyses of Gas — Influence of Atmospheric Pressure and Temperature on Gas — Residual
Products — Appendix — Description of Retort Settings, Buildings, etc., etc.

Practical Geometry and Engineering Drawing ; a

Course of Descriptive Geometry adapted to the Requirements of the
Engineering Draughtsman, including the determination of cast shadows
and Isometric Projection, each chapter being followed by numerous
examples ; to which are added rules for Shading Shade-lining, etc.,
together with practical instructions as to the Lining, Colouring, Printing,
and general treatment of Engineering Drawings, with a chapter on
drawing Instruments. By GEORGE S. CLARKE, Lieut. R.E., Instructor
in Mechanical Drawing, Royal Indian Engineering College. 20 plates^
4to, cloth, 15^.

The Elements of Graphic Statics. By Professor

KARL VON OTT, translated from the German by G. S. CLARKE, Lieut.
R.E., Instructor in Mechanical Drawing, Royal Indian Engineering
College. With 93 illustrations , crown 8vo, cloth, $s.

The Principles of Graphic Statics. By GEORGE

SYDENHAM CLARKE, Lieut. Royal Engineers. With 112 illustrations.
4to, cloth, 12s. 6d.

PUBLISHED BY E. & F. N. SPON.

The New Formula for Mean Velocity of Discharge

of Rivers and Canals. By W. R. KUTTER. Translated from articles in
the ' Cultur-Ingenieur,' by Lowis D'A. JACKSON, Assoc. Inst. C.E.
8vo, cloth, I2J. 6ct.

Practical Hydraulics ; a Series of Rules and Tables

for the use of Engineers, etc., etc. By THOMAS Box. Fifth edition,
numerous plates, post 8vo, cloth, 5>r.

A Practical Treatise on the Construction of Hori-
zontal and Vertical Waferwheels, specially designed for the use of opera-
tive mechanics. By WILLIAM CULLEN, Millwright and Engineer. With
ii plates. Second edition, revised and enlarged, small 4to, cloth, \2s.6d.

Aid Book to Engineering Enterprise Abroad. By

EWING MATHESON, M. Inst. C.E. The book treats of Public Works
and Engineering Enterprises in their inception and preliminary arrange-
ment ; of the different modes in which money is provided for their
accomplishment ; and of the economical and technical considerations by
which success or failure is determined. The information necessary to
the designs of Engineers is classified, as are also those particulars by
•which Contractors may estimate the cost of works, and Capitalists the
probabilities of profit. Illustrated, 2 vols., 8vo, I2J. 6d. each.

The Essential Elements of Practical Mechanics;

based on the Principle of Work, designed for Engineering Students. By
OLIVER BYRNE, formerly Professor of Mathematics, College for Civil
Engineers. Third edition, with 148 wood engravings, post 8vo, cloth,
7s. 6d.

CONTENTS :

Chap. I. How Work is Measured by a Unit, both with and without reference to a Unit
of Time— Chap. 2. The Work of Living Agents, the Influence of Friction, and introduces
one of the most beautiful Laws of Motion— Chap. 3. The principles expounded in the first and
second chapters are applied to the Motion of Bodies— Chap. 4. The Transmission of Work by
simple Machines — Chap. 5. Useful Propositions and Rules.

The Practical Millwright's and Engineers Ready

Reckoner; or Tables for finding the diameter and power of cog-wheels,
diameter, weight, and power of shafts, diameter and strength of bolts, etc,
By THOMAS DIXON. Fourth edition, I2mo, cloth, 3.?.

Breweries and Mailings : their Arrangement, Con-
struction, Machinery, and Plant. By G. SCAMELL, F.R.I.B.A. Second
edition, revised, enlarged, and partly rewritten. By F. COLYER, M.I.C.E.,
M.I.M.E. With 20 plates, 8vo, cloth, i8j.

A Practical Treatise on the Manufacture of Starch,

Glucose, Starch-Sugar, and Dextrine, based on the German of L. Von
Wagner, Professor in the Royal Technical School, Buda Pesth, and
other authorities. By JULIUS FRANKEL ; edited by ROBERT HUTTER,
proprietor of the Philadelphia Starch Works. With 58 illustrations,
344 pp., 8vo, cloth, 18^.

io CATALOGUE OF SCIENTIFIC BOOKS

A Practical Treatise on Mill-gearing, Wheels, Shafts,

Riggers, etc. ; for the use of Engineers. By THOMAS Box. Third
edition, with II plates. Crown 8vo, cloth, 'js. (id.

Mining1 Machinery: a Descriptive Treatise on the

Machinery, Tools, and other Appliances used in Mining. By G. G.
ANDRE, F.G.S., Assoc. Inst. C.E., Mem. of the Society of Engineers.
Royal 4to, uniform with the Author's Treatise on Coal Mining, con-
taining 182 plates, accurately drawn to scale, with descriptive text, in
2 vols., cloth, 3/. 12s.

CONTENTS :

Machinery for Prospecting, Excavating, Hauling, and Hoisting — Ventilation — Pumping—
Treatment of Mineral Products, including Gold and Silver, Copper, Tin, and Lead, Iron,
Coal, Sulphur, China Clay, Brick Earth, etc.

Tables for Setting out Curves for Railways, Canals,

Roads, etc., varying from a radius of five chains to three miles. By A.
KENNEDY and R. W. HACKWOOD. Illustrated, 32mo, cloth, 2s. 6d.

The Science and Art of the Manufacture of Portland

Cement, with observations on some of its constructive applications. With
66 illustrations. By HENRY REID, C.E., Author of 'A Practical
Treatise on Concrete,' etc., etc. 8vo, cloth, i8j.

The Draughtsman's Handbook of Plan and Map

. Drawing-, including instructions for the preparation of Engineering,
Architectural, and Mechanical Drawings. With numerous illustrations
in the text, and 33 plates (15 printed in colours}. By G. G. ANDRE,
F.G.S., Assoc. Inst. C.E. 4to, cloth, 9*.

CONTENTS :

The Drawing Office and its Furnishings — Geometrical Problems — Lines, Dots, and their
Combinations — Colours, Shading, Lettering, Bordering, and North Points — Scales — Plotting
— Civil Engineers' and Surveyors' Plans — Map Drawing — Mechanical and Architectural
Drawing — Copying and Reducing Trigonometrical Formula, etc., etc.

7^ he B oiler-maker s andiron Ship-builder s Companion,

comprising a series of original and carefully calculated tables, of the
utmost utility to persons interested in the iron trades. By JAMES FODEN,
author of ' Mechanical Tables,' etc. Second edition revised, with illustra-
tions, crown 8vo, cloth, 5-r.

Rock Blasting: a Practical Treatise on the means

employed in Blasting Rocks for Industrial Purposes. By G. G. ANDRE,
F.G.S., Assoc. Inst. C.E. With 56 illustrations and 12 plates, 8vo, cloth,
los. 6d.

Surcharged and different Forms of Retaining Walls.

By J. S. TATE. Illustrated, 8vo, sewed, 2s.

PUBLISHED BY E. & F. N. SPON. u

A Treatise on Ropemaking as practised in public and

private Rope-yards, with a Description of the Manufacture, Rules, Tables
of Weights, etc., adapted to the Trade, Shipping, Mining, Railways,
Builders, etc. By R. CHAPMAN, formerly foreman to Messrs. Huddart
and Co., Limehouse, and late Master Ropemaker to H.M. Dockyard,
Deptford. Second edition, I2mo, cloth, 3^.

L ax tori s Builders and Contractors Tables ; for the

use of Engineers, Architects, Surveyors, Builders, Land Agents, and
others. Bricklayer, containing 22 tables, with nearly 30,000 calculations.
4to, cloth, 5-r.

Laxtoris Builders and Contractors Tables. Ex-
cavator, Earth, Land, Water, and Gas, containing 53 tables, with nearly
24,000 calculations. 4to, cloth, 5-r

Sanitary Engineering: a Guide to the Construction

of Works of Sewerage and House Drainage, with Tables for facilitating
the calculations of the Engineer. By BALDWIN LATHAM, C.E., M. Inst.
C.E., F.G.S., F.M.S., Past-President of the Society of Engineers. Second
edition, with numerous plates and woodczits, 8vo, cloth, I/. ioj.

Screw Cutting Tables for Engineers and Machinists,

giving the values of the different trains of Wheels required to produce
Screws of any pitch, calculated by Lord Lindsay, M.P., F.R.S., F.R.A.S.,
etc. Royal 8vo, cloth, oblong, 2s.

Screw Cutting Tables, for the use of Mechanical

Engineers, showing the proper arrangement of Wheels for cutting the
Threads of Screws of any required pitch, with a Table for making the
Universal Gas-pipe Threads and Taps. By W. A. MARTIN, Engineer.
Second edition, royal 8vo, oblong, cloth, is., or sewed, 6d.

A Treatise on a Practical Method of Designing Slide-

Valve Gears by Simple Geometrical Constrtiction, based upon the principles
enunciated in Euclid's Elements, and comprising the various forms of
Plain Slide- Valve and Expansion Gearing ; together with Stephenson's,
Gooch's, and Allan's Link-Motions, as applied either to reversing or to
variable expansion combinations. By EDWARD J. COWLING WELCH,
Memb. Inst. Mechanical Engineers. Crown 8vo, cloth, 6s.

Cleaning and Scouring : a Manual for Dyers, Laun-
dresses, and for Domestic Use. By S. CHRISTOPHER. i8mo, sewed, 6d.

A Handbook of House Sanitation ; for the use of all

persons seeking a Healthy Home. A reprint of those portions of Mr.
Bailey-Denton's Lectures on Sanitary Engineering, given before the
School of Military Engineering, which related to the "Dwelling,"
enlarged and revised by his Son, E. F. BAILEY-DENTON, C.E., B.A.
With 140 illustrations, 8vo, cloth, 8*. 6d.

12 CATALOGUE OF SCIENTIFIC BOOKS

Treatise on Valve-Gears, with special consideration

of the Link-Motions of Locomotive Engines. By Dr. GUSTAV ZEUNER.
Third edition, revised and enlarged, translated from the German, with the
special permission of the author, by MORITZ MULLER. Plates, 8vo,
cloth, I2s. 6d.

A Pocket-Book for Boiler Makers and Steam Users,

comprising a variety of useful information for Employer and Workman,
Government Inspectors, Board of Trade Surveyors, Engineers in charge
of Works and Slips, Foremen of Manufactories, and the general Steam-
using Public. By MAURICE JOHN SEXTON. Second edition, royal
32mo, roan, gilt edges, $s.

The Strains upon Bridge Girders and Roof Trusses,

including the Warren, Lattice, Trellis, Bowstring, and other Forms of
Girders, the Curved Roof, and Simple and Compound Trusses. By
THOS. CARGILL, C.E.B.A.T., C.D., Assoc. Inst. C.E., Member of the
Society of Engineers. With 64 illustrations, drawn and worked out to scale,
8vo, cloth, 12s. 6d.

A Practical Treatise on the Steam Engine, con-
taining Plans and Arrangements of Details for Fixed Steam Engines,
with Essays on the Principles involved in Design and Construction By
ARTHUR RIGG, Engineer, Member of the Society of Engineers and of
the Royal Institution of Great Britain. Demy 4to, copiously illustrated
with woodcuts and 96 plates, in one Volume, half-bound morocco, 2.1. 2s. ;
or cheaper edition, cloth, 2$s.

This work is not, in any sense, an elementary treatise, or history of the steam engine, but
is intended to describe examples of Fixed Steam Engines without entering into the wide
domain of locomotive or marine practice. To this end illustrations will be given of the most
recent arrangements of Horizontal, Vertical, Beam, Pumping, Winding, Portable, Semi-
portable, Corliss, Allen, Compound, and other similar Engines, by the most eminent Firms in
Great Britain and America. The laws relating to the action and precautions to be observed
in the construction of the various details, such as Cylinders, Pistons, Piston-rods, Connecting-
rods, Cross-heads, Motion- blocks, Eccentrics, Simple, Expansion, Balanced, and Equilibrium
Slide-valves, and Valve-gearing will be minutely deali with. In this connection will be found
articles upon the Velocity of Reciprocating Parts and the Mode of Applying the Indicator,
Heat and Expansion of Steam Governors, and the like. It is the writer's desire to draw
illustrations from every possible source, and give only those rules that present practice deems
correct.

Barlow s Tables of Sqiiares, Cubes, Square Roots,

Cube Roots, Reciprocals of ail Integer Numbers ^lp to 10,000. Post 8vo,
cloth, 6s.

Caimis (M.) Treatise on the Teeth of Wheels, demon-
strating the best forms which can be given to them for the purposes of
Machinery, such as Mill-work and Clock-work, and the art of finding
their numbers. Translated from the French, with details of the present
practice of Millwrights, Engine Makers, and other Machinists, by
ISAAC HAWKINS. Third edition, with \% plates, 8vo, cloth, 5*.

PUBLISHED BY E. & F. N. SPON. i3

A Practical Treatise on the Science of Land and

Engineering Surveying, Levelling, Estimating Quantities, etc., with a
general description of the several Instruments required for Surveying,
Levelling, Plotting, etc. By H. S. MERRETT. Third edition, 41 plates
with ilhistrations and tables, royal 8vo, cloth, I2J. 6d.

PRINCIPAL CONTENTS :

Part i. Introduction and the Principles of Geometry. Part 2. Land Surveying; com-
prising General Observations — The Chain — Offsets Surveying by the Chain only — Surveying
Hilly Ground — To Survey an Estate or Parish by the Chain only — Surveying with the
Theodolite — Mining and Town Surveying — Railroad Surveying — Mapping— Division and
Laying out of Land — Observations on Enclosures — Plane Trigonometry. Part 3. Levelling —
Simple and Compound Levelling— The Level Book — Parliamentary Plan and Section —
Levelling with a Theodolite — Gradients — Wooden Curves — To Lay out a Railway Curve —
Setting out Widths. Part 4. Calculating Quantities generally for Estimates — Cuttings and
Embankments — Tunnels— Brickwork — Ironwork — Timber Measuring. Part 5. Description
and Use of Instruments in Surveying and Plotting — The Improved Dumpy Level — Troughton's
Level — The Prismatic Compass — Proportional Compass — Box Sextant — Vernier — Panta-
graph — Merrett's Improved Quadrant — Improved Computation Scale — The Diagonal Scale-
Straight Edge and Sector. Part 6. Logarithms of Numbers — Logarithmic Sines and
Co-Sines, Tangents and Co-Tangents — Natural Sines and Co-Sines—Tables for Earthwork,
for Setting out Curves, and for various Calculations, etc., etc., etc.

Saws: the History, Development, Action, Classifica-
tion, and Comparison of Saws of all kinds. By ROBERT GRIMSHAW.
With 220 illustrations, 410, cloth, I2J. 6d.

A Sitpplement to the above ; containing additional

practical matter, more especially relating to the forms of Saw Teeth for
special material and conditions, and to the behaviour of Saws under
particular conditions. With 120 illustrations, cloth, 9-r.

A Guide for the Electric Testing of Telegraph Cables.

By Capt. V. HOSKICER, Royal Danish Engineers. With illustrations,
second edition, crown 8vo, cloth, 4^. 6d.

Laying and Repairing Electric Telegraph Cables. By

Capt. V. HOSKICER, Royal Danish Engineers. Crown 8vo, cloth,
3J. 6d.

A Pocket- Book of Practical Rules for the Proportions

of Modern Engines and Boilers for Land and Marine purposes. By N. P.
BURGH. Seventh edition, royal 32mo, roan, 45-. 6d.

Table of Logarithms of the Natural Numbers, from

i to 108,000. By CHARLES BABBAGE, Esq., M.A. Stereotyped edition,
royal 8vo, cloth, 7.5-. 6d.

To ensure the correctness of these Tables of Logarithms, they were compared with Callett's,
Vega's, Mutton's, Briggs', Gardiner's, and Taylor's Tables of Logarithms, and carefully read
by nine different readers ; and further, to remove any possibility of an error remaining, the
stereotyped sheets were hung up in the Hall at Cambridge University, and a reward offered
to anyone who could find an inaccuracy. So correct are these Tables, that since their first
issue in 1827 no error has been discovered.

14 CATALOGUE OF SCIENTIFIC BOOKS

The Steam Engine considered as a Heat Engine : a

Treatise on the Theory of the Steam Engine, illustrated by Diagrams,
Tables, and Examples from Practice. By JAS. H. COTTERILL, M.A.,
F.R.S., Professor of Applied Mechanics in the Royal Naval College.
8vo, cloth, I2J-. 6d.

The Practice of Hand Turning in Wood, Ivory, Shell,

etc., with Instructions for Turning such Work in Metal as may be required
in the Practice of Turning in Wood, Ivory, etc. ; also an Appendix on
Ornamental Turning. (A book for beginners.) By FRANCIS CAMPIN.
Second edition, with wood engravings, crown 8vo, cloth, 6s.

CONTENTS :

On Lathes — Turning Tools — Turning Wood — Drilling — Screw Cutting — Miscellaneous
Apparatus and Processes — Turning Particular Forms — Staining — Polishing— Spinning Metals
— Materials — Ornamental Turning, etc.

Health and Comfort in Hoiise Building, or Ventila-
tion with Warm Air by Self-Acting Suction P(nver, with Review of the
mode of Calculating the Draught in Hot- Air Flues, and with some actual
Experiments. By J. DRYSDALE, M.D., and J. W. HAYWARD, M.D.
Second edition, with Supplement, with plates, demy 8vo, cloth, 'js. 6d.

Treatise on Watchwork, Past and Present. By the

Rev. H. L. NELTHROPP, M.A., F.S.A. With 32 illustrations, crown
8vo, cloth, 6s. 6d.

CONTENTS :

Definitions of Words and Terms used in Watchwork — Tools — Time — Historical Sum-
mary— On Calculations of the Numbers for Wheels and Pinions;, their Proportional Sizes,
Trains, etc. — Of Dial Wheels, or Motion Work — Length of Time of Going without Winding
up — The Verge — The Horizontal — The Duplex — The Lever — The Chronometer — Repeating
Watches— Keyless Watches — The Pendulum, or Spiral Spring — Compensation — Jewelling of
Pivot Holes — Clerkenwell — Fallacies of the Trade — Incapacity of Workmen — How to Choose
and Use a Watch, etc.

Spons Engineers' and Contractors Illustrated Book

of Prices of Machines, Tools, Ironwork, and Contractors' Material;
and Engineers* Directory. Third edition, 410, cloth, 6s.

Algebra Self-Taught. By W. P. HIGGS, M.A.,

D.Sc., LL.D., Assoc. Inst. C.E., Author of 'A Handbook of the Differ-
ential Calculus,' etc. Second edition, crown 8vo, cloth, 2s. 6d.

CONTENTS :

and Proportionate Parts — Transformation of System of Logarithms — Common Uses of
Common Logarithms — Compound Multiplication and the Binomial Theorem — Division,
Fractions, and Ratio— Continued Proportion — The Series and the Summation of the h'eries —
Limit of Series— Square and Cube Roots— Equations— List of Formulae, etc.

PUBLISHED BY E. & F. N. SPON.

JUST PUBLISHED.

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A SUPPLEMENT

SPONS' DICTIONARY OF ENGINEERING,

Cifril, fpcdjmtiral, UKlitarg, mtb |takl

EDITED BY ERNEST SPON, MEMB. Soc. ENGINEERS.

THE success which has attended the publication of ' SPONS' DICTIONARY OF
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Abacus, Counters, Speed
Indicators, and Slide
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Dynamo - Electric and
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Rock Drills.

Rolling Stock.

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Steel.

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Tramways.

Well Sinking.

NOW COMPLETE.

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: SPONS' ENCYCLOPEDIA

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Full text of "Philipp Reis: inventor of the telephone. A biographical sketch, with documentary testimony, translations of the original papers of the inventor and contemporary publications"

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