, 1918-04-25
PaNSZLe wWr 0FcATEIaHALAe JN9E

track layers are used I'm plantatiop vor, In c,bo
tne Fhiipplnes' Java, Hawaii. South Africa and
so on throughout the world. There are almost
II huhureu OF them at work in Hawaii, taken
there from California where the tractor fourishes.
Ihey are hauling logging trains In Maine, Mon
Jana, Wisconsin. Minnesota and Canada as eff
ciehty as they are transporting supplies in the
mining regions Of the West. On the dusty roads
VI the fahamint range, where the steep grades
wear down the spirit of the strongest mule teams
and where water stations are few and far he
tween track layers are as valuable for freighting
as they are in the heat and whirllng sand clouds
of the Mojave Desert.
Ihere are at the present time about fifteen
hrms engaged in making tractors with the end
less belt type of drive. There are between eight
and ten thousand tractors of this type of al. diff
ferent makes now in use in the world.
Factories are now speeding the construction of
these track-laying tractors for the use of the
United States in the field artillery, marine corps,
signal corps and other branches of the service.
Armored track layers are used in hauling sup
plies over ground that motortrucks cannot travel
on. Today manufacturers of track layers find the
war orders tax their facilities to such an extent
that they are not able to keep up with the COM
mercial demand.
The advance of the tank over the earth sug-
gests the movement Of Il living creature. Yet its
operation Is simple. The track layer lays its
track down in front of the frame. rolls over II,
picks 1t up again and repeats the process.
The track consists of n broad-geared belt or
endless chain Of flat steel links, which is put In
motion by large chain-supportlng wheels which
fit into the inside of the belt by gears. 1t thus
resembles a belt stretched around the front and
rear wheels of an automobile and presenting a
fiat surface on the ground.
The outside of the belt is comprised of broad
links known as track plates which are ridged to
prevent their slipping. The inside of the belt
contains the twin tracks upon which rest the
rollers that support the weight of the tractor.
Nine out of ten persons who watch n tractor
demonstration for the first time get the impress
sion that the track itself is moving upon the
ground. The illusion is created by the fact that
the top of the belt Is observed to be going for
ward. But the forward motion Of that part of
the belt is taken up by the forward motion of
the car. If the car is raised from the ground and
the motor set in motion the belt will be seen re-
volving around the supporting chain wheels. In
this case the tank is absolutely at rest.
There are two belts, one on either side of the
car. When the car goes straight ahead both belts
revolve at even speed. But the right and left
hand tracks may be operated Independently.
Through the operation of clutches that CORE
spond to those In an automobile one track may
be brought to n standstil while the other track
continues to move at normal speed. The tank
with all its power applied on one side will make
q sharp turn. If the right hand track is moving and
the left is still the tank will turn to the left.
The weight Of the tank Is distributed along the
whole length of the track. In the %crumbllng new
ly reclaimed land of the San Joaquin delta, Call
fornia, track layers travel on soil that will not
support the weight Of Il man, much less q horse.
They will pass over cracks in the crumbling e0rth
that a horse could fall into, dragging harrows
over the uneven ground until all crevices are