The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1895-11-09
DOCTOR OF MACHINERY.
Curious Defects Which He Must Dis
cover and Remedy.

new 1OTh lriDuue.
Among the multiudinous trades and pro-
fessions in New York there are many which
are entirely unknown, even by name, to
the general public. One of the least known
in machinery. The work Of a machinery
specialist Is far higher than hat of a
skilled engineer. and many years of expert
ence and special training are necessary to
fit the expert for his duties. There are only
about half a dozen of these men in the
country, one in every large city. When
anything goes wrong with a machinery
the engineer in charge, frequently the
builder of the engines, cannot discover, the
machinery doctor Is called in Every chief
engineer of a big plant may be called a
specialist so far as the machinery under
his charge is concerned. but the specialist
In machinery is an expert in engines or
Though he has never seen the engine be-
fore, he rapidly diagnoses the case and pre-
scribes a remedy, just as a doctor does for
a sick patient. The instrument most used
by him is a ~dentophone, which consists of
a thin steel rod about a foot long, which he
holds between his teeth and applies to the
head of the cylinder. To the practiced ear
Of the expert every sound transmitted from
the cylinder tells a story. The working of
the piston in the cylinder, and. indeed. of
the whole engine, can be heard distinctly
in this manner by anybody. but it takes an
expert toetell just what these sounds mean.
In the case of a mysterious knocking
which was heard In the cylinder of the big
80 re 81 III q Ao
not long ago., an expert was called in to de-
termine the cause. Every method had been
tried to discover where the trouble was, but
without avail. Bearings were examined,
the cylinder was taken apart, and every
part well oiled, all to no purpose. When the
expert came he traced the mysterious
knocking from the cylinder, along the pis-
ton rod, crank shaft, and through the main
shaft. away off among the looms, where
one of the looms was found to be the cause
of the trouble.
often an experts services are required i'm
the case of synchronizing looms. If all the
looms in a big spinning factory happen to
beat together, as sometimes happens, the
vibration is strong enough to bring the
building down. For the same reason SOL
diers always break step when going over
measured tramp of the many feet all strik-
ing the ground at the same time. would
seriously endanger the structure: The
erted In a particular way. Every substance
in nature has a keynote, and when a sound
of the same pitch is caused near 1t a con-
siderable amount of vibration is produced.
When the great tubular bridge was being
built across the Menai straits, which d.
vide England from the Island Of Anglesea,
a travelling violinist nearly caused the col
lapse of the whole structure. He happened,
while playing. to hold for a considerable
time a note which CHANGED to be the Key
note OF the huge bridge structure. The
sound echoed along the vast tube and re-
echoed with ever-increasing force until the
whole bridge vibrated as IL an earthquake
was taking place. The bridge engineer, VINO
was nearby. instantly OWNED the cause,
and stopped the playing OF the violinist.
Part OF the business of the machinery
doctor consists in so arranging the distribu-
ton Of looms and other machinery hat
their working will not endanger the stabil-
iy of the factory. Defects in a boiler can
also be instantly determined by the prac-
ticed ear Of the specialist. A plate In
the boiler is selected which is
known to be in good condition.
of the sound made when the plate Is
struck with a hammer. All the other plates
are struck in the same way. and any one
the correct pitch, Is examined and replaced.
A case is on record where a machinery
specialist was crossing the ocean and de-
tected specialization in the center Of the
shaft, thereby a~verting what might have
been a serious accident in midocean. Meas
ures were taken to strengthen the shaft in
the place where the quick ear of the expert
detected weakness. and when the vessel was
locked his suspicious proved correct.
Few men even with the most exhaustive
training become experts at this business. as
Ii requires a marvellous quickness of ear
and delicate perception of sound with which
few men are blessed. Technical knowledge
is of little avail of itself, and a fine engin-
eer might be a poor machinery doctor. just
as a great musician might make an in
different piano tuner. Whenever a big mill
Is erected, a specialist is always consulted
as to the placing of the machinery. and his
fee is generally well worth the expense
and trouble which an injudiciouS distribu-
ton of machines may cause.