The Cairo daily bulletin. (Cairo, Ill.) 1870-1872, 1871-05-23
Marrow Gauge Railroad.

From the Chicago Tribune, May 2ol
We are asked the question how ,an a
three foot gauge railway be constructed
for $4,000 per mile, when it costs $4,000
per mile to build four foot ten inch
gauge track on the best located routes.
The cost of building and equipping q
railroad Of narrow gauge is in the pro-
portion Of its cube rute to that Of u wide
gauge. Tho cube OF feet is II. The
cube Of feet 81 inches, which is the mar
rowest of existing gauges, equals lo4. and
in this proportion does the cost Of build
ing and equipping roads Of these respect
much three-foot road as $40, 400 will con-
struct of 4 feet 8! inch track.
To illustrate this principle; A man
t,cice the height Of boy will weigh eight
times rs much. If the boy is 3 feet high,
and weighs, say, 4Oa pounds, man feet
So inches, built in the same proportion,
will weigh 1856 pounds, although be is on "
feet 81 inches taller than the boy. A
common freight car weighs eight to ten
tons, and carries burden Of ten tons. A
freight locomotive weighs about thirty
tons. On q three-foot track it has been
found that iron-made freight cars need
weigh but $500 pounds, and were amply
strong enough to carry three tons Of
freight. In addition to this case the oar
can carry four times its own weight,
whereas on tho wide track it can bear n
load only, or slightly, exceeding its own
weight. Twelve narrow gauge iron cars
only weigh as much as an ordinary wood |
and iron freight truck, but they will con- |
vey thisty-six tons of freight wherever
the big truck can safely move under only
one-fourth as much freight. An empty
freight train of one locomotive, tender
and twenty trucks will weigh over 400
tons, and when fully loaded, as much more
or 400 tons. One-half OF the power of
the locomotive is, therefore, consumed in
moving ''dead weight" and the other half
in moving burden. A locomotive, as we
said, weighs 80 tons ITS tender, with
coal aud water, weighs II tons, and the
two together Al tons; so the dead pe,oht
OF the engine and tender Is "a per cent. of
the empty train, or ii per cent of the
laden train. The weight on each driving
wheel Of = locomotive Is between fre and
sic tons. The injury sustained by the
track, under this enormous pressure on
single point of tho rail, must be obvious
at glance. One locomotive, exerting u |
pressure Of six tons on each of its driving |
wheels, will do the rails more harm than |
hundred locomotives running at the same |
speed whose wheels press the rail with but |
one ton and u half of pressure. In the one
case the iron is pressed beyond its resisting
power; its fibre is strained and crushed, |
and the rails soon wear out under such ex.
cessive weight. But to obtain the neces-
sary adhesive power to move the train and |
its load up grades, locomotives must be !
built enormously heavy, which speedily
deteriorates and destroys the rails; but |
there Is no help for il on wide track ex-
cept by the use Of steel rails, and they arc |
liable to snap like pipe-slems under the |
influence Of frost and the weight of the |
locomotive.
On the narrow gauge track the locomo- |
tive may be tank engine, and carry its |
own coal and water and dispense with a |
tender. IL need not weigh but six or eight |
tons with its supply of fuel and water. |
The pressure OF its wheels will, therefore
be but one and a half to two tons each. |
A pony locomotive, weighing six tons,
with a ton and half pressure on the rail
from each wheel, will draw at the same
'peed more than one quarter as much
load as thirty ton locomotive, because
; part of the weight Of the latter has to
be thrown on the guiding wheels,
winch subtracts rather than adds to the
power Of the machine Four such
pony engines will do the work Of the big
one with ease, Together they will weigh,
with their fuel and water about thirty
Ions; whereas the big locomotive and its
lender WEIGHS fcrty-seven tons. The for
mer will move three tons Of freight for |
each ton Of "dead-weight;" the latter will |
scarcely move but one ton Of freight to =
ton Of dead weight. In PAST niger loco
motives and cars, the relative superiority