THE TRANSPORT OF AMMUNITION AND ARTILLERY
The System of Ammunition Supply--The Traction Engine--French
Four-Wheeled Tractors for Hauling Guns--German Gun-Carrying
Motors.
The system of maintaining ammunition supplies for troops in the field
is very similar to that already described in connection with the supply
of food. Stocks of ammunition are kept at depôts of the Army Ordnance
Corps at various points between the base and railhead, to which they
are forwarded as required. From railhead they are brought forward daily
by the motor lorries of the divisional ammunition parks to a convenient
re-filling point, where they are transhipped on to horsed ammunition
carts for distribution in detail. With the troops entirely dependent
on the motor vehicle for the maintenance of their supplies both of food
and of ammunition, there is no need to labour the enormous importance
of mechanical transport in modern warfare, or the terrible consequences
which would follow anything approaching a general failure in the
reliability of the machines used.
For the haulage of very heavy guns some form of engine power is of
course essential, and the ordinary steam traction engine provides the
most obvious solution, since it is to be assumed that if the roads
and bridges to be traversed are sufficiently strong to bear the gun
itself, they will also bear the engines which haul it. The big traction
engine is a very British product, and it is interesting, if not quite
satisfactory, to note that the huge siege guns of the German army are
stated to be hauled by engines of British origin. For lighter guns,
the steam tractor, or small traction engine, can be employed, but very
many efforts have been made to dispense with its service in favour of
an internal combustion tractor, less dependent on constant renewal of
fuel and water supplies.
[Illustration: A BRITISH “MARSHALL” INTERNAL COMBUSTION TRACTOR
SUITABLE FOR THE HAULAGE OF ARTILLERY.]
[Illustration: _“The Autocar” photograph._
A FRENCH PETROL-ELECTRIC FOUR-WHEEL-DRIVE TRACTOR, THE WHEELS OF WHICH
ARE SPECIALLY SHOD TO FACILITATE TRAVELLING OVER ROUGH GROUND.]
In the brief sketch already given of the principal trials and
manoeuvres in which motor transport has figured, some indication has
been afforded of the attempts made by the British Government in this
direction. The most consistent, and probably the most successful,
efforts have however been made by our neighbours, the French, who
have for this special purpose given much encouragement to the
development of internal combustion tractors driving all four wheels.
The movement dates back about three years, and owes its origin to the
need for hauling 155 m/m siege guns along roads and across country.
The first type of tractor produced to meet the requirement was the
Chatillon-Panhard. The weight of the first type with full load was
in the neighbourhood of 22 tons, and more recently efforts have
been made to evolve lighter types weighing about 14 tons with their
load, the belief being that these rather smaller machines would be
of great general utility. Some very important trials in this
connection took place in France early in 1914, four types of tractor
participating, namely, the Latil, the Schneider, the Chatillon-Panhard
and the Renault. The first-named is a development of the Latil type of
lorry, in which the engines drive the front wheels, and the whole power
plant is concentrated on to the fore carriage, the back wheels and the
platform being really nothing more in principle than a two-wheeled
trailing vehicle. An extension of this system involves the use of three
differential gears, one for each pair of wheels, and a third as a
balance gear half way along the vehicle from which the drive is taken
fore and aft through longitudinal shafts and worm gearing. All four
wheels are steered as well as driven.
In the Schneider, the drive is taken from a gear box containing
two sets of sliding gears through cardan shafts to the front and
back axles, and alternatively, when required, to a capstan enabling
the engine to haul through the medium of a wire rope. In the
Chatillon-Panhard, the transmission is so arranged as to involve no
universal joints, and only one differential gear. This is mounted on a
transverse countershaft, and the power is taken to the wheels through
bevel gears at the ends of the countershaft, and four diagonal shafts
driving in their turn auxiliary shafts upon which are bevels engaging
with similar bevels on the wheels. The Renault is a very simple machine
of its type. The drive is taken fore and aft from the gear box by
cardan shafts leading to differential gears on the front and back axle.
Either one of the differentials can be locked when desired to help
the machine to find its way out of difficult positions. Yet another
machine which is available to the French Government, though it did not
take part in the trials mentioned, employs electrical machinery in
place of the usual mechanical transmission gear. The engine drives an
electric dynamo, which supplies current to four electric motors, one
for each wheel. On the whole, the French four-wheel driven tractors
have performed very well under severe tests, and it is stated that
approximately 300 tractors of one or other of the types mentioned
are available for military service, though it is possible that this
estimate is somewhat exaggerated.
[Illustration: _“The Autocar” illustration._
A KRUPP MOTOR GUN-CARRYING LORRY, SHOWING THE RAMPS UP WHICH THE GUN
HAS BEEN HAULED SERVING ALSO THE PURPOSE OF HOLDING IT SECURELY IN
POSITION.]
For the rapid transport of light artillery various special machines
have been devised, providing either for the carriage of a gun upon the
platform of a motor lorry, or for the construction of a gun-carrying
vehicle forming one complete unit. In this branch of development the
Germans have shown the most initiative, and Krupps have got out several
interesting designs. In all of these strong motor lorry chassis are
used. A usual system is to fit, by hinging to the back of the chassis,
strong ramps up which the gun may be hauled, either by the power of the
motor engine or by other means. When on the platform, the gun wheels
sink into depressions formed to take them and also bear up against
shaped vertical stops. When the gun is in place the ramps are swung
over, and are so designed that their ends can then be conveniently
attached rigidly to the vertical stops, the ramps themselves also
bearing against the gun wheels and holding them quite secure; or in an
alternative method, the ramps are arranged to grip the axle of the gun
carriage.
Special designs are for motor vehicles capable of a good turn of speed,
and arranged to carry guns especially intended for fighting against
aeroplanes or airships, and consequently so arranged as to allow of
their muzzles being swung up until the gun assumes a vertical position.
Other special arrangements of motor vehicles are those providing for
the carriage of machine guns, but this type perhaps comes more properly
under the title of an armoured motor car.