st complete exhaustion of that little band of Alpini heroes, they
were able to retake only a half of the summit. Here, at a
ten-metres-high ridge which roughly bisects the _cima_, the Alpini held
the Austrians, and here, in turn, the latter held the reinforcements
which I was finally able to send to the Alpini's aid. There, exposed to
the fire of the guns of either side (and so comparatively safe from
both), a line was established from which there seemed little probability
that one combatant could drive the other, at least without a radical
change from the methods so far employed.

[Sidenote: Idea of blowing up positions.]

"The idea of blowing up positions that cannot be taken otherwise is by
no means a new one. Probably it dates back almost as far as the
invention of gunpowder itself. Doubtless, if we only knew of them, there
have been attempts to mine the Great Wall of China. It was, therefore,
only natural that, when the Austrians had us held up before a position
it was vitally necessary we should have, we should begin to consider the
possibility of mining it as the only alternative. The conception of the
plan did not necessarily originate in the mind of any one individual,
however many have laid claim to it. It was the inevitable thing if we
were not going to abandon striving for our objective.

[Sidenote: Engineering operation of great magnitude.]

"But while there was nothing new in the idea of the mine itself, in
carrying out an engineering operation of such magnitude at so great an
altitude and from a position constantly exposed to intense artillery
fire there were presented many problems quite without precedent. It was
these problems which gave us pause; but finally, despite the prospect of
difficulties which we fully realized might at any time become
prohibitive, it was decided to make the attempt to blow up that portion
of the summit of the Col di Lana still held by the enemy.

[Sidenote: Gelasio Caetani the engineer.]

"The choice of the engineer for the work was a singularly fortunate one.
Gelasio Caetani--he is a son of the Duke of Sermoneta--had operated as a
mining engineer in the American West for a number of years previous to
the war, and the practical experience gained in California and Alaska
was invaluable preparation for the great task now set for him. His
ready resource and great personal courage were also incalculable assets.

[Sidenote: Miners from North America.]

"Well, the tunnel was