The Coeur d'Alene press. (Coeur d'Alene, Idaho) 1906-1907, 1907-10-10
An ENGINE TREADMILL
|The Modern Method of Testing a
Locomotive.
RACING AT A STANDSTILL.

AhEAu
steel Monster Are Driven to Their
Limit to Test Every Detail.
IN the old days when an engine was
milf it was the custom to test her by
lending her out on the road. Rudyard
KIpling once wrote a story describing
how great locomotive was tried out
|rhis was true at that time 1t was
usual then to take the engine, hitch a
Iot of heavy freight cars to her and
lend her out over the line, on levels
Ind tangents, on curves and grades,
until she showed exactly what was In
her for those purposes, says Harper's
Weekly.
But nowadays the railroad men want
10 know more, and they want to know
n before they intrust a scheduled pas
keuCer or freight train to her mercies,
so they put the engine on a treadmill
'The iirst thing they do with her then
tc allow her wheels to revolve TO
|raracity, for in that the maximum
kpeed is figured, Then she is coupled
10 an arrangement with a dial attach
nent for the purpose of testing her
Dulllng power. BY a backward pull
be engineer makes her draw the
Equivalent of everything from a bag
nge car to a mile long freight train.
Now she is to all intents and pur-
bosses racing over the meadows, the
rack clear and the way straight; now
l.. A,.fIz 40
Ide of large town and painting like
human being in distress. Stronger
md stronger grows that backward pull
until No. 0000 finds herself slowing I'D.
After a time she is required to start or
Try to start again, with every known
condition against her, every brake, bar,
Ock and lever set wrong This Is to
earn her starting power-a most i'm
portant thing in railroading.
All the time the engine was pulling
ind hauling, racing and checking, her
bteam gauges and water gauges had
been telling little stories of their own,
md these stories were listened to with
interest. They were telling about the
ressure of the steam in the boiler,
Etth the amount of water and coal
HSed. They were saying whether the
mount Of fuel was producing the max
mum Of steam or whether there was
mistake somewhere. They were tell
ng as plainly as the words will wheth-
br the boiler was large enough for the
rate or the CRATE too large for the
boiler.
By this severe test by the experts
f the new locomotive on the tread
mill these skilled men can learn ex-
betty what every part of the machine
5 doing, and woe to the part that
ails in its share. 1t means another
pip to the construction department
md the supplying of new parts
Speed and pull and pressure and eff
ectiveness of parts do not end the
ests Of No 5000. Another important
md interesting thing is determined
Ehlle she is on the treadmill, and that
hen best load. 1t is strange, but
Fue. tnat engines for some reason are
ever exactly alike. They may be of
be same type, parts made feom the
ltAlAGl II Liza 81 lIilJ lhGlbg anu llib
anne workmen may construct them
the same plan, but just the same
hey differ Old engineers will tell
GU Of that, and therefore there must
e test for each machine.
Once the test was to hitch on cars
an engine "uptil she laid down and
ried," as they said-that is. till she
Ould not pull another car over the line
larked out. Nowadays they never do
bat but by a scientific arrangement
pulleys, levers and wheels strike
be golden mean between too much
feight and too littie-the exact point
here the machine can do its best
TOrk in the shortest time under the
lost adverse conditions.
The principle is the same as In the
aSe Of a hodcarrier who overloads
mself for climb up ladder and Is
lenefore wear,ed by a single trip,
hlle the man who loads light makes
any trips, with a minimum of effect.
I'D therefore accomplishes more. The
odern railroad superintendent wants
get the most bricks over his division
Fery day.
The proposition of putting locomo-
We on a treadnilI and running it at
lu speed just to find out what it can
is little startling. The demands
ade upon locomotives today have ma
rally changed the conditions Of for
er years. Longer cars, heavier trains,
CHER speed aud longer runs are all
lct0rs which must be dealt with.
othing short of the most accurate
nowledge obtainable regarding every
ement Of design and its effect on the
leration of the machine as a whole
eets the needs of the man who builds
locomotive.
There are certain qualities OF To-
motive which can only be deter
med by actual trial in service-for
stance. The starting power Other
lslities cannot he well determined
ben the machine Is in service, be
Use when running at high speed
nditions cannot be kept uniform for
long running period Of time. II the