503
OF ENGINEERING FORMULA.
Rule for the Centre of Gravity of
Locomotives.
0 = Horizontal distance line of centre of gra-
vity from driving axle.
L — Load on leading wheels.
T = Load on trailing wheels.
I — Distance of leading axle from driving axle.
t = Distance of trailing axle from driving axle.
B = Length of wheel base.
W = Total weight of engine.
- LI - T t 5
C =---------measured towards leading axle.
If T t exceeds L I, then
T*-LZ , , , ,
G =-----— measured towards the trailing
axle.
This rule applies to six-wheeled engines when
the driving wheel is placed between the leading
and trailing wheels. In four-wheeled engines,
if L exceeds T, the horizontal distance of the
centre of gravity measured from the trailing
L B
axle = . If T exceeds L, the distance mea-
W
T B
sured from the leading axle = . If T = L,
the centre of gravity is half-way between the two
axles.
Consumption of Oil on Railways.
In America the consumption of oil is to
■Jg-th of a pint per train mile.
Twenty pints of oil lubricate 8 journals of
carriages 5000 milts, or 1 pint to 250 miles.