For three days and nights
he drove the troops of his combined Second and Third Armies against
the enemy's lines all along the Isonzo. His system was to attack by
day and then at night resist the enemy's counterassaults on his newly
won positions. The Italians retained all the ground they won during
these days of terrific fighting, and captured 3,500 prisoners.

By the 20th of July their confidence had increased to such an extent
that they determined upon a night assault. But next morning Cadorna
received word from his aeroplane scouts and his spies that the enemy
was massing for a supreme effort. The Italian advance was stayed and
every man was set at work helping the engineers strengthen the
trenches.

On July 21, 1915, there came a complete lull. The next day the
Austrians opened their attack with a concentrated bombardment. During
the period of Italian advance the railways had been piling up the
Austrian shells and German gunners had been sent by the Crown Prince
of Bavaria to help serve the heavy howitzers rushed to the Carso from
the Julian Alps and the Tyrol and Trentino salients. With the design
to cut the Italian line of communication, the main Austrian infantry
attack was delivered toward Gradisca where the Italians had
constructed their principal bridges across the Isonzo. The infantry
massed behind the neighboring hills and under cover of a tremendous
artillery bombardment advanced in close formation. The first line of
Italian troops seemed about to be swept away when the gunners on the
heights across the river got the range and poured into the advancing
Austrians a massed fire from all their 500 pieces. General Boroevics's
advance was pounded to pieces; the Italians brought up reenforcements
and charged and captured the lines from which the Austrians had
delivered their assault, taking 2,000 prisoners.

[Illustration: A cloud of poisonous gas released by Italian troops
from tanks concealed in the thicket.]

On July 23, 1915, the archduke ordered another attack upon the Italian
positions near the sea on the edge of the Carso tableland. This was
really an effort to recapture Monfalcone; but it failed, although the
Italians did not dare risk pursuit over the rough ground. Later two
Austrian divisions, advancing from San Michele and San Martino against
Sagrado were repulsed with heavy losses.

By July 25, 1915, the Italians were able to attack and capture some of
the intrenchments on the slopes of San Mart