Infantry redoubts.
Since Sir George Clarke published his first edition in 1890 continental
ideas have expanded a good deal. The foregoing statement as to the three
categories of defences would be accepted anywhere now: the differences
of opinion come in when we reach the stage of classifying under the
first head the permanent works to be constructed in peace time. In most
countries these would include forts with guns for the artillery duel,
forts with safety armaments, fixed batteries with or without armour, and
forts for infantry only. Sir George Clarke will have no armour for guns
except in certain special cases of barrier forts. Heavy guns and
howitzers requiring permanent emplacements (concrete platforms, &c.)
must either be well concealed or be provided with alternative positions.
The only permanent works which he admits are for infantry. They are
redoubts of simple form intended for 350 or 400 men, with casemate
accommodation for three-fourths of that number. Fig. 61 shows the
design:--two rows of casemates, one under the front parapet, one under a
parados; frontal musketry defence; obstacle consisting of entanglements,
mines, &c., with or without escarp and counterscarp.
[Illustration: FIG. 60.--Transportable Cupola for 5.7-cm. Gun (Friedr.
Krupp A.G.).]
"The intervals (he says) between the infantry redoubts may be about
2500 yds.; but this will necessarily depend upon the conformation of
the ground. Where there are good artillery positions falling within
the sphere of protection of the redoubts, large intervals will be
permissible. Thus, in the case of an extended line of defence where
the ground offers marked tactical features, the idea of a continuous
chain of permanent works may be abandoned in favour of groups of
redoubts guarding the artillery positions. In this case, the redoubts
in a group might be distributed on a curve bent back in approximately
horse-shoe form."
[Illustration: From Sir George S. Clarke's Fortification, by permission
of John Murray.