The Bennington evening banner. (Bennington, Vt.) 19??-1961, 1910-12-12


where you're dead wrong" The engi-
neer rested his gnarled fist across his
knee as If it We're a fifteen pound
monkey wrench. Eyes. sir" he re-
peated, IF you've got that idea you're
wrong. just like folks are likely to be
on railroad matters which they don't
know anything about. Now, the fact
is that a certain type of engine can be
stopped quicker If it has half dozen
freight cars hooked on to 1t. That's
so because there are brakes on each OF
the cars, and they all grind into the
wheels when you sling on the emer-
gency. Why wouldn't II stop quicker
If you had a dozen cars on instead Of
six? Well, sonny, for the simple rea-
son that the weight Of the train, or,
rather. the momentum, 0vercomes the
braking strength of your air, and so
you're carried along. If you had less
than six cars it would be just the
other way-you wouldn't have enough
braking power to overcome what
weight you have got Yes, sir, with
every freight train and with every
passenger train there ID a certain
number of cars necessary to make the
train most effective when 1t comes to
stopping quickly. This is very prac'
teal question too. An engineer will
say to himself, Well I've got more
cars ON today; I'll have to put on
brakes sooner In order to stop just
right ut the station
II once heard an engineer say that
an engine with baggage car and two
passenger coaches travelling at the rate
of thirty-five miles an hour would re-
quire about 600 feet to stop and trav-
cling at twenty-five miles an hour
would require 400 feet to halt. Now.
he was Just guessing, or else he had
particular train and particular condi-
tons In mind, and most likely partic-
ular times IN mind The fact is you
can't tell within what distance train
can be stopped.
"Why, take the same type OF engine
duu tnt o1llt yDC VI AOathto aaA AAA
them over the same track and apply
the brakes In precisely the same man
ner and the two trains will not stop
in the same distance Of track. Indeed,
take the same train over the very
same track at different times, run her
at exactly the same speed and apply
the brakes in the very same manner
and you can't stop in the same dis
lance Engineers would like to stop at
each station at precisely the same spot
that they did the day before. DO they
ever do IT. No, son, they don't. be
cause 1t can't be done.
THE stopping Of a train depends OF
conditions. just ms said before. En-
gineers who have travelled over a par
ticular road for years can't do II. Some
times the conditions vary TO such al
extent that the train Is run past the
station. Everybody has seen that done
And then the engineer says things un
der his breath and backs uD his trair
to let the passengers on and 10 TAKE
ON baggage. Sonny. engineers nevel
know within yards where their trains
will stop.
Freight trains are more uncertain
than passengers. This is so because !
doesn't matter us much. An applica
ton Of ten pounds OF air may produce
no braking at all. due to the wear o.
the system, and, on the other hand, M
teen pounds might put on more brak'
than the engineer wanted. He ma!
throw ON a small quantity OF air, an'
without expecting II the emergenc,
brakes get into action as result
When the brakes are already on tn
engineer may release them little AM
by so doing release them entirely, s.
that the train leaps forward. SO, yo'
see. you can't always tell what tn
brakes are going to do.
"You wouldn't suppose that the ten
perature of the rails would make an,
difference about brakes, would you
It's n fact. A rule OF thumb is that
train will brake twice as quickly 4
the winter as In the summer Tn
wheels stick TO the rails more whe
they are cold. The scientific folk tel
YOU that the cohesion Is greater. And
another thing, the oil ON the rail whe
II IS warm Is more slippery. All IN
steel rcds. pipes. etc. on a warm da
are expanded. and so they have
move through greater distances TO b
} come effective. When they are col
tracted by the cold the brakes grip N
wheels that much quicker and tightc
with the same amount or air that 20
applied on n warm day.
"You see sonny. every road In n
country keeps tabs ON the temperatur
three or four times a day all alon
its lines. Temperature Is quite a
important thing In rallroad!ng. A
this goes 10 show that there Is quite
lot OF science In running trains. An
! never saw man yet who had bee
. IN the service so long that he couldn
learn heap Of things. The fellow
who think about their business al