Clarke courier. [volume] (Berryville, Va.) 1869-1997, 1907-08-07
aHENGINE TREADM|LL
The Modern Method of Testing a
Locomotive.
RACING AT A sTANpsTlLL.


Steel Monster Are Driven to Their
Limit TO Test Every Detail.
In the old days when an engine was
built 1t was the custom to test her by
Eending her out ON the road. Rudyard
kipling once wrote story describing
how a great locomotive was tried out.
This was true at that time. IL was
usual then to take the engine. hitch a
lot OF heavy freight cars TO her and
send her out over the line. ON levels
and fangents. ON curves and grades.
until she showed exactly what was In
her for those purposes. says Uarper's
Weekly.
But nowadays the railroad men want
to know more, and they want TO know
IL before they intrust scheduled pas-
senger or freight train to her nercies.
SO they put the engine on n treadmilI.
The first thing they DO with her then
Is to allow her wheels to revolye to
capacity, for In that the maximum
speed Is figured. Then she is coupiei
to an arrangement with dial attach
ment for the purpose OF testing her
pulling power BY backward pull
the engineer makes her draw the
equivalent OF everything from bag
gage car to mile long freight train.
Now she Is to all intents ana p,,--
poses racing over the meadows. the
track clear and the way straight: now
she is striking the grade on The other
side OF large toxin anu pantinS Ike
a human being In distress. Stronger
and stronger grows that backward pulI
until No. 5000 finds herself slowing up
After time she is required To start or
try TO start again, with every known
condition against her. every brake. bar.
lock and lever set wrong This * to
learn her starting powcr-a most i'm
portant thing I'm railroading.
All the time the engine was pulling
and hauling. racing anI checking. her
steam gauges and water gauges had
been telling little stories OF their own.
and these stories were listened to with
interest They were telling about the
pressure OF the steam In the boiler.
with the amount OF water and coal
used. They were saying whether the
amount OF fuel was producing the max
imum OF steam or whether there was
n mistake somewhere. They were tell
Ing as plainly us the words will wheth-
er the boiler was large enough for the
CRATE or the crate too large for the
boiler.
BY this severe test by the experts
OF the new locomotive on the tread
mill these skilled men can learn ex-
actly what every part OF the machine
Is doing. and woe TO the part that
falls In its share. IL means another
trip TO the construction department
and the supplying OF new parts.
Speed and pull and pressure and eff
fectivcness OF parts do not end the
tests OF No. COCO. Another Important
and Interesting thing Is determined
while she IL on the treadmill. and that
Is her best load. II Is strange, but
true. that engines for some reason are
never exactly alike. They may he OF
the same type. parts made from the
same pattern may go into them. and the
same workmen may construct them
on the same plan, but just the same
they differ. Old engineers will tell
you OF that. and therefore there must
be test for each machine.
Once the test was Il hitch OH cars
10 an engine until she laid down and
cried" rs they saId-that Is, till she
could not pull another car over the line
marked out. Nowadays they never do
that. but by n scientific arrangement
OF pulleys. levers and wheels strike
the golden mean between too much
fsrat nj Q
whore the machine can do its best
work In the shortest time under the
most adverse conditions.
The principle Is the same as In the
case OF holcarrier who overloads
himself for climb up ladder and is
therefore wcaried 10y single trip,
while the man who loads light makes
many trips. with q minimum OF effect,
and therefore accomplishes more. The
modern railroad superintendent wants
TO get the most bricks over his division
every day.
The proposition OF putting locomo-
tive on treadmlll and running 1t ct
full speed Just To find ont what IL can
do Is 4 little startling. The demands
made upon locomotives today have ma
terially changed the conditions OF for
mer years. Longer cars, heavier trains.
higher speed and longer runs are all
factors which must be dealt with.
Nothing short Of the most accurate
knowledge -obtalnable regarding every
element OF design and it's effect on the
operation of the machine rs whole
meets the needs OF the man who builds
a locomotive
There are certain qualities OF To-
connective which can only be deter
mined by actual trial in service-for
Instance. the starting power. Other
qualities canno: tie well determined
when the machine Is IL service, be-
cause when running ut high speed
conditions cannot Ee kept uniform for
long running period of time. II the
test were started on q level straight
track. curve or hill would be
reached before tho running conditions
had become sufficiently established to
measure. The difficulty Of conducting
test at high speed can hardly be APP
preciated. Some OF tho n.en making
the test are often required to ride in
small box secured to the outside Of
the engine near the cowcatcher, where
the noise, dust and Jar are frightfui.
The testing machine itself Is MOTH
Ing but huge treadmill The loco
motive stands still when being tested,
while Its driving wheels ore spinning
around as fast as If It were pulling
n fY-oin af f,,fl ctNaa.I