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while regular sections are attached to the Navy for operating
captive balloons from warships。 Although the Zeppelin and
aeroplane forces have come to the front in Germany； and have
relegated the captive balloon somewhat to the limbo of things
that were； the latter section has never been disbanded； in fact；
during the present campaign it has undergone a somewhat spirited
revival。
The South African campaign emphasised the value of the British
balloon section of the Army； and revealed services to which it
was specially adapted； but which had previously more or less been
ignored。 The British Army possessed indifferent maps of the
Orange Free State and the Transvaal。 This lamentable deficiency
was remedied in great measure by recourse to topographical
photographs taken from the captive balloons。 The guides thus
obtained were found to be of extreme value。
During the early stages of the war the hydrogen was shipped in
cylinders from the homeland； but subsequently a manufacturing
plant of such capacity as to meet all requirements was
established in South Africa。 The cylinders were charged at
this point and dispatched to the scene of action； so that it
became unnecessary to transport the commodity from Britain。 The
captive balloon revealed the impregnability of Spion Kop； enabled
Lord Roberts to ascertain the position of the Boer guns at the
Battle of Paardeburg； and proved of invaluable assistance to the
forces of General White during the siege of Ladysmith。
CHAPTER II
THE MILITARY USES of THE CAPTIVE BALLOON
Although the captive balloon is recognised as indispensable in
military operations； its uses are somewhat limited。 It can be
employed only in comparatively still weather。 The reason is
obvious。 It is essential that the balloon should assume a
vertical line in relation to its winding plant upon the ground
beneath； so that it may attain the maximum elevation possible： in
other words； the balloon should be directly above the station
below； so that if 100 yards of cable are paid out the aerostat
may be 100 yards above the ground。 If a wind is blowing； the
helpless craft is certain to be caught thereby and driven
forwards or backwards； so that it assumes an angle to its
station。 If this become acute the vessel will be tilted；
rendering the position of the observers somewhat precarious； and
at the same time observing efficiency will be impaired。
This point may be appreciated more easily by reference to the
accompanying diagram。 A represents the ground station and B
the position of the captive balloon when sent aloft in calm
weather； 300 feet of cable being paid out。 A wind arises and
blows the vessel forward to the position C。 At this point the
height of the craft in relation to the ground has been reduced；
and the reduction must increase proportionately as the strength
of the wind increases and forces the balloon still more towards
the ground。 At the same time； owing to the tilt given to the
car； observation is rendered more difficult and eventually
becomes extremely dangerous。
A wind； if of appreciable strength； develops another and graver
danger。 Greater strain will be imposed upon the cable； while if
the wind be gusty； there is the risk that the vessel will be torn
away from its anchoring rope and possibly lost。 Thus it will be
seen that the effective utilisation of a captive balloon is
completely governed by meteorological conditions； and often it is
impossible to use it in weather which exercises but little
influence upon dirigibles or aeroplanes。
The captive balloon equipment comprises the balloon； together
with the observer's basket； the wire…cable whereby it is anchored
and controlled； and the winding apparatus。 Formerly a steam
engine was necessary for the paying in and out of the cable； but
nowadays this is accomplished by means of a petrol…driven motor；
an oil…engine； or even by the engine of an automobile。 The
length of cable varies according to the capacity of the balloon
and the maximum operating height。
The average British balloon is able to lift about 290 or 300
pounds； which may be taken to represent the weight of two
observers。 On the other hand； the French and German balloons are
able to carry four times this weight； with the exception of the
French auxiliaries； which are designed to lift one observer only。
The balloons of the two latter Powers have also a greater maximum
altitude； it is possible to ascend to a height of some 2；000 feet
in one of these。
The observing station is connected with the winding crew below
either by a telephone； or some other signalling system； the
method practised varying according to circumstances。 In turn the
winding station is connected with the officer in charge of the
artillery； the fire of which the captive balloon is directing。
The balloon observer is generally equipped with various
instruments； such as telescope； photographic cameras； and so
forth； so as to be able； if necessary； to prepare a topographical
survey of the country below。 By this means the absence of
reliable maps may be remedied； or if not regarded； as
sufficiently correct they may be checked and counter…checked by
the data gained aloft。
Seeing that the gas has to be transported in cylinders； which are
weighty； it is incumbent that the waste of this commodity should
be reduced to the minimum。 The balloon cannot be deflated at
night and re…inflated in the morningit must be maintained in
the inflated condition the whole time it is required for
operation。
There are various methods of consummating this end。 One method
is to haul in the balloon and to peg it down on all sides；
completing the anchorage by the attachment of bags filled with
earth to the network。 While this process is satisfactory in calm
weather； it is impracticable in heavy winds； which are likely to
spring up suddenly。 Consequently a second method is practised。
This is to dig a pit into the ground of sufficient size to
receive the balloon。 When the latter is hauled in it is lowered
into this pit and there pegged down and anchored。 Thus it is
perfectly safe during the roughest weather； as none of its bulk
is exposed above the ground level。 Furthermore it is not a
conspicuous object for the concentration of hostile fire。
In some instances； and where the military department is possessed
of an elaborate equipment such as characterises the German army；
when reconnaissance is completed and the balloon is to be removed
to another point； the gas is pumped back into the cylinders for
further use。 Such an economical proceeding is pretty and well
adapted to manoeuvres； but it is scarcely feasible in actual
warfare； for the simple reason that the pumping takes time。
Consequently the general procedure； when the balloon has
completed its work； is to permit the gas to escape into the air
in the usual manner； and to draw a fresh supply of gas from