The sun. [volume] (New York [N.Y.]) 1833-1916, 1878-07-14
THE SIXTH AVENUE NOISES.
MR. EDISON PREPARING TO GEr nv dC-
CURITE RECORD or THEM.
Having In III. shop the whose Noise Made ny
Trnin On the Metropoiitaa Elevated
Rond, to Determins tts Locality aud Cause.

day In arranging comp de grdce for Prof.
Hughes tho Englishman. who denies having
merged the telephone bodily into mcrophonc.
Nevertheless he found timo To give brief
chronicle OF his operations for the lessen ng NJ
tho noise ON tho Metropolitan Elevated Rail-
road.
Ny mission. Mr. Ellison said, is to deter-
mine the sources VI the noise simply, aud DOES
not cover the recincation Of 1t. Mr. Lowry, tho
attorney for the road, il tho attorney also for
thcWcstorn Union Telegraph Company. IIo
knows mo intimately. and knows that am IA
miliar with the subject OF sounds. lie 1t was
who proposed me to the Metropolitan Elevated
Railroad Company as one who could determine
the sources OF noises on their road. Of which
lately SO much complaint has been made. when
WIS engaged. WAS engaged simply TO hnd
out tho sources OF tho noise. and not at all to
correct H. That is the mission Of the engineers
and, indeed. the cause OF the trouble once de-
termined, the remedy IL as easily applied by
one as 10y another.
Il have been up and down on the road now
as many rs one hundred times. My assistants
have been with me. and we have taken accurate
chronicles. We have driven in the trains lain
In the convolution ~ the Rirders wandered
upon the track lurked in saloons-not whiskey
saloons. ice-ercam saloons along the way. and
htuuleu tne vibrations from all lmaknaDo
points.
There has been general mention in the
newspapers OF little instrument which have
employed in determining the degree and the
position of noise. This instrument is the
phonsutogrsph Of Leon Scott. an invention that
Is familiar to the shelves II every scientific
school and college In the country. To be sure
nave made changes in IT. and have applied tho
Lrinclple OF II especially To- my own purposes.
Inc pnUnAutOgrNnl il not nj all the gf tina
paonogrnph. For instance. II you shout the
word How IN the uhonautograph 1t records
perhaps eighty vibrations. whereas the phOno-
graph records seven or eight hundred. | am
ut present engaged in making the Scott phon.
disk.'' ''''' - '""'""- ''0
Mr. Ellison then showed the chronicles which
ne had already made 10y means Of the phonau-
tQgraph. that ne has employed twice upon the
elevated road and fifteen or twenty times upon
the Pennsylvania Central road, the latter FOR
the purpose OF analogy. In the Scott phonauto-
graph. as Is proved in every hc school,
the vibrations produced by certain cultural
sounds are marked down upon cylinder Ii
has no compass and will not register sounds OF
nigh pitch In Mr.. Elisons use Of the phon-
autograph the process ia Ms follows:
Aim of lamphark. This is accomplished by
holding paper over a lamp Of burning camphor.
The sheet then IL wound over a cylinder similar
to the cylinder OF the photograph. paper
ympanum. susceptible to the air conclusions
arising from any, noise. has attached to it =
straw. To the end OF the straw II fixed n single
camel's hair. and this single cAmel's hair trails
upon the hackened paper, removing the lamp
black and leaving n fne white line M the cyin-
der Is turned. Lamphlack cast upon glossy
paper has the properties at once Of sticking and
Of yielding to the slightest scratch In the
phonautograph. as used 10y Mr.. Edison. in adj
dtton 10 the camePs hair attached to the straw
and subject 10 the vibrations of the tympanum.
another camels hair Is traied upon the cylin-
der through the action OF teegraphic key
When the key If struck the camels hair rests
touched the camel's hair hangs the shade of an
inch Above II. For an insthnc- t. Illustrate how
this compound machine works, II the cylinder
IL turned, any ordinary noise entering in At the
mouthpiece over the tympanum causes the lat
ter to vibrate. and the cancels hair attached
makes moro or less wavy streak over the
paper. II the noise Is especially great at any
one point. the wave in the line upon the paper
an operator IL engaged IN manipulating the
kew When. for instance. the truck passes over
aJont in the rails. the operator presses the key
anu leaves an especial marx upon the paper at
when all is done the paper is observed. Sup
pose the mark made by the pressure Of the
ieegrHphic key, ia opposite a. deep wave in tho
line produced by the cameVs hair attached 70
NE straw and to the ympsnnm, that would
show that at the moment the truck struck tho
Joint there was an especially loud noise. SO.
again. at other points. or at other moments.
| whore or when noise = expected. the opera
| tor presses the key. and tbs records from the
two cauels hairs are compared. OF course.
where the wave is greatest the noise IL greatest.
and, equally OF course. through repeated cN-
| pertinent. the Geographic key. through the
anipuation Of the operator. comes 10 mark
tile deepest wave. and Consequently the point
Of the greatest noise, After tho sheet is coy.
cred with the record it IL removed from the
A. everybody has seen cologne sprayed from a
| bottle 10y \ rubber contrivHnce. THIS preserves
the lamp black AGAINST casual rubbing. and the
But shortly" Mr.. Edison said. lam going
no noises 81 The the eeysd upon ,e
more delicate and sensitive instrument. and IL
VIII register the slightest Of sounds shall
| bring home the sheets OF tinfoil with me. set
the, whole noise OF the Metropolitan Elevated
an mere sdnas s cRSR Of sosad ha
| now loose in Sixth avenue. and then | shall set
lelsurely to work and put them into table.
volume. / shall divide the Comprehensive
noise Of the road into 100 parts, and then say.
from this. SO many from that. and 81 many
from the other
/ know that the iron rods forming the lattice
Ike an Tnaned reed they arr %9 eight hsS G fest
long, and uniixed. save at their ends, Now. a
| heavy train going along at high speed makes
! force. The force must escape somewhere: 1t
| escapes into the iron rods Of the lattce. Force
| In these causes them TO vibrate; | have noted
them swaylng two inches out Of the perpendc-
ular; | hays caught hold q them when they
were in motion and been obliged TO let 20 in a
| hurry. the force in them was great When
they are set whrrlng they make music. like the
music that they make ithAy were harmonious :
as 1t is they all work different tune and pro-
| uuce ulh'ofu suppose lhHt. instead Oi these
| iron rods. OF which there are forty between
| every two sets Of posts. there were forty tuned
| reeds nobody would DENY that the vibrations
caused by n flying train would set them to
| making fine music. But these untuned rods
| get the same vibrations. Why then shouldn't
| they make noise
| Another source of noise Is the pine sleepers
| and another the uneven surface OF the rails.
| The rails in parts of the Pennsylvania road are
! smooth rs glass compared with those of the
| Metropolitan Elevated The sleepers being
pine. will not hold bolt. and so, At frequent in
| tervals the rails have sprung from their posi-
| ton. and when train passes these are banged
| down upon the wood and make another sort Of
| noise. In some places you can put your hand
| between the rails and the ties. Some persons
may think II easy to determine the causes of
sounds. but II isn't. If they think il so easy,
Just let them tell what II IL that makes the differ
ence OF sound in two violins. Let the. wood be
! the same and the size and pattern be the same.
| and let any man attempt to make them Just the
same still no two Niollns oan be made to sound
| alike. Do you sne that teegranhic sounder
| You may make five hundred of them all of the
| same metal and in the same gauge and yet no
| two will have the same sound. To an unaccus-
| toned ear. the noise on the Metropolitan Ele-
| waited seems the same noise throughout. But il
| isn't. 1t varies materially III different Sec
tons.
road and everywhere 10 vibration. With per-
! feet soidity there would be no noise. There is
| n stretch OF elevated road in London which runs
| over "A stone emhnn kmpnt You have seen IL in