IS:con-
graphs
10dern
reting
cimate
ossible
e posts
flected
Figure
nagni-
ry with
. (about
lasted
r rims
k dots
1g Cir-
enches
earth
t even
e grey
alized
rere it
ds are
Espe-
Frc. 12. Vertical of a strong point in sandy ground, showing trenches, bunkers,
emplacements and machine-gun nests.
Fic. 13. The same photo as above with symbols.