Greenmantle - John Buchan

The Deve Boyun lines seemed to me monstrously strong, and I remembered
the merits of the Turk as a fighter behind strong defences. It looked as if Russia
were up against a second Plevna or a new Gallipoli.
Then I took to studying the flanks. South lay the Palantuken range of
mountains, with forts defending the passes, where ran the roads to Mush and
Lake Van. That side, too, looked pretty strong. North in the valley of the
Euphrates I made out two big forts, Tafta and Kara Gubek, defending the road
from Olti. On this part of the map Stumm's notes were plentiful, and I gave them
all my attention. I remembered Blenkiron's news about the Russians advancing
on a broad front, for it was clear that Stumm was taking pains about the flank of
the fortress.
Kara Gubek was the point of interest. It stood on a rib of land between two
peaks, which from the contour lines rose very steep. So long as it was held it was
clear that no invader could move down the Euphrates glen. Stumm had appended
a note to the peaks—'not fortified'; and about two miles to the north-east there
was a red cross and the name 'Prjevalsky'. I assumed that to be the farthest point
yet reached by the right wing of the Russian attack.
Then I turned to the paper from which Stumm had copied the jottings on to
his map. It was typewritten, and consisted of notes on different points. One was
headed 'Kara Gubek' and read: 'No time to fortify adjacent peaks. Difficult for
enemy to get batteries there, but not impossible. This the real point of danger, for
if Prjevalsky wins the peaks Kara Gubek and Tafta must fall, and enemy will be
on left rear of Deve Boyun main position.'
I was soldier enough to see the tremendous importance of this note. On Kara
Gubek depended the defence of Erzerum, and it was a broken reed if one knew
where the weakness lay. Yet, searching the map again, I could not believe that
any mortal commander would see any chance in the adjacent peaks, even if he
thought them unfortified. That was information confined to the Turkish and
German staff. But if it could be conveyed to the Grand Duke he would have
Erzerum in his power in a day. Otherwise he would go on battering at the Deve
Boyun ridge for weeks, and long ere he won it the Gallipoli divisions would
arrive, he would be out-numbered by two to one, and his chance would have
vanished.
My discovery set me pacing up and down that cellar in a perfect fever of