New-York tribune., 1877-05-18
THE SPEAKING TELEPHONE.
FIRST LECTURE OF PROF. A. GRAHAM
BELLS COURSE.

OVER THE WIRE.
Prof. A. Graham Bell gave last night at
Chickering Hall the first OF course OF three lectures
upon the telephone The lectures illustrated by
magic lantern pictures thrown on screen, and by thc
performances OF the telephone itself The telephone Is
used 10 transmit sounds between Chckering Hail. New
York and New-BrIinswck ~ ia distance OF 81 miles
The platform was largely occupied by gentle
men who are distinguished by their connection
with scientific research, with the practical bust
ness Of the telegraph Among those present were fro7
F. A. p. Barnard and o. n Rood OF Columbia College,
Profs Henry Morton and a. NJ Mayer OF the stevens i
sttute of Technology HOboken; Mr.. Cyrus W. Field hr
William Orton and Gen Ecker; and Messrs. Preece ana
Wheeler who have been deputed by British Government
authority to make an examination and report OF tue
methods and practice Of the electric telegraph III inc
United States The audience vac not large onc' prlo
pay because the lecture had not been widely noteeu
aud little pains had been taken TO secure popular '
est; nevertheless, the han was al least hail nlou WIN
attentive listeners.
telegraph pulc was erected IN the auditorium near
tbe stage and wires from it were connected win tue
ordinary telegraph machinery on the stage anu ''o
with tlree small telephones. of which one was Oh tue
stage and two were suspended over the heads oil inc
audience, Just beneath the gallery
THE LECTURE
Prof Bell apolOgized for an awkward HIS
chance winch would compel him To use INFERIOR Hs'Iu
m lUrinU
are not here suppose thcy somewhere on inc r''i
road betyecn this city and Boston, else in some eA
press Office The telephones have here are lht'hae" W
work on a short circuit OF mile but the other tee
phoucs intended for "a long circuit, are not hei'' "
bringing forward my telephone before yon Won" nave
YOU understand that this subject ai'hOuEh nave NC"
working at it for many years consider stll IN us III
fancy DO not bring this invention before you Us 1"
complete invention. bring as 1t s you can Ju"He oi
yourselves GAppiause.l
II gives me very great plea urc to accede 10 lc I
ton winch has been 80 kindly extended to me 10 "'"N
before the citizens Of NewIork the snbect oi c ec
tIc telephone. propose in the course oil my Iem'iAH
this evening give you some ideas oi ""a' n'' '''
dome by others N regard o the transmission Of sounds
hv fac electrical current. Too few OF us
have given aEy attention TO the nature ol
souud itself | speak to you at the present
moment YOU hear what say, and the thing So"nd eNH's
in the air between my mouth and your ears "h"t u
that thing sound Now if we come to CONSIDER Wha'
sound is We had better picture to ourselves an atmosphere
filed with little dense partlccsparticles OF air h"Ved
backward and forwarl-lnd tls motion backward and
forward il what we call sound particle OF air moved
al The rate OF 81 times per second will produce sound
As the rapidity ia increased the musical tone
rises higher and hi ghcr and when yhraoho some
thousands OF times per second, the ptch Is very Rh III
deed Now il We consider the particles o; air moving
during the production Of sound We slaii ihd ul' mo
ton characterized by three pecuErltes tch 'i Souu
loudnrss of sound ana mbrc orquality OF sound sup
pos, You picture in your minds eye one particle OF air
IL moves backward and forward through lhis
space. we will sly, thiry-twO times in one sec
Oud IL viii then produce very low hlsl'al
tone. The rapidly II vioratcS the hiShcr
viii the tone bc. But the extent OF lis vibrations be
varied il it ybratcs to great extent II VIII DE i"u
musical tone 80 upon the amplitude Of the vibration
depends the ouducss Of The sound. But what gives u'
n Is
vowel for instance differ from the vowel a. What are
tnc pcculires in the notion Of the particles OF air that
belong TO sounds OF different quality II has been dis
covered by Henhnl,z that differences Of quality are due
To differences If shape OF vibrations that vowel sou a.
for instance i3 chord OF several notes differing in their
pitch and intensity. In fact for every diheeht souhu
there IL a different form Of vibration.
Prof Ben then illustrated the carves which various
yoy,c! sounds produced, the curves being exhibited by
means OF TIE magic lantern Prof Bells experiments
began uy the construction OF an artificial ear Inc Vbra
tons which different sounds caused in this ear were com
muncacd 10 a attached 10 It, Beneath thc oiE'I
end of the straw bia,aencd strip Of paper was moved
AT an cqua rate and the point OF the straw marked the
vibrations in blachcucd surface. In successive PIE
lures on tho screen the Artificial ear with the
straw ant tie moving paper beneath and the various
curves produced by different sounds. were distinctly
shown Each vowc, produced its own characteristic
curycs The proper curves of each Of the English vowel
sounds were shown, aud also of certain Polish aud iun
,arian vowcls Prof. Be continued
You will therefore understand from the experiments
that different qualities Of sound produced by differ
eut shac, o. the vibration Now If want to produce
sound by electricity the problem before us Is TO move
The air after the electricity is transmitted IN tie same
way that 1t moved by the human voice Whch
the transmission started. In my remarks
ny own researches regarding tae uahshIss.on ,
OF sOunds h.' gy the foundation FOR tat Dy showing
what experin 'nts Eay" be II made before
All previous experiments have aimed not at the pro.
duciOu OF Uricd5tc spc.ch but at the production oi
musical tone. Tao VIBRATION for the musical tone Is
much less Intricate than for the hum speech. The
first person who discovered that sound could be pro
dCcad by means OF electricity was the late POL fdSe
Of salem, Mass, "ho 4'1cg4cIeu u nSig o.' iU"s i,
fact In hc year is1G lie was eNpehhchunS
had insated wire, andr was stfIch ny tGe laJ, tnal
vheu hc passed q current Of electricity through tLs
rent soprci Their, was also a sound. lie published this
in Siitmti's JoU'l0j ia 1887. The sounds produced
he were TO pass q current OF electricity and
stop it very quickly and do this frequently,
sounds and if Lc were make these very RAPID thcy
would produce musical Tone HIS experiments proved
duccd from the bar OG iron by simply transmitting anu
inrrUpuLg the electricity passing around tde co oil
Vlrc.
1he experiments Of Prof. Page repeated and am.
picd ~ Pot. dc ia Lyc OF France. An lnsuumtht oi
rhco;Omc; il makes and breaks tie circuit Descriptions
were given aud dil-rJu5 SHOWN OF tc trlril4h OF
tour OF Copcnuagcn ara Llsha Gray Of Chicago were
succcsycIy exhibited on o screen, ana Their pccudri
ties eNpaIur1. 20 each 0i thc inventors IN this c!d OF
research Prot BED visited to give the full hOnOrs that
their dJc. For himself lee claimed the discovery OF an
instrument that the for all pitches ana yHrle
ties Of sound the U Ic receiving at the sending
station, and that required HU battery.
The experiment., shown by PrU!. Ben did not essen
italy Gcr 'I1fu those at the private exhibition, except
in having more distant connection, and i'm transmitting
music iru.u peculiar construction The reefs
OF tho organ Blown DY wiud-sct iu motion by WIND
at New Brunswick, - miles away II was the organ
wi I
laboratory. The experiments III when mufl-
cal sounds transmitted made with
battery current Of electricity. The current
was mado and hOkcu by the vibration uf thr
reeds. Above each reed there is metal screw and
- -E..I.- !. l. -