scarce in the
camp.

At length, however, one of those to whom he had spoken mentioned his
story to the king, who at once sent for him, and saw the importance of
the news he brought. O'Brian himself had no idea of the object of
Sarsfield's expedition, but the king instantly guessed that it was the
siege train. He therefore ordered a large body of cavalry to be
immediately despatched to meet the artillery on its way, and protect it
into camp.

All day, Sarsfield remained in concealment among the mountains, until,
towards evening, the train came in sight, moving slowly with its escort
of two troops of dragoons along the high road. He watched it until it
halted, and encamped for the night, in a field beside the highway. He
waited until the horses were picketed, and the men engaged in making
their encampment for the night. Then the Irish cavalry burst down from
the glen in which they had been hiding. The officer in command sounded to
horse, but it was too late; before the men were in the saddle, the Irish
were upon them, and in a moment the two troops of dragoons were dispersed
or killed.

Sarsfield's men at once set to, to collect the powder waggons, pontoons,
and baggage of every description. The great guns were filled with powder
to the muzzle, and then buried two-thirds of their length in the earth.
The whole mass of siege equipage was piled above them, and a train of
gunpowder was laid to the store in the centre. The men then drew off to a
distance. A match was applied to the train, and the whole blew up with a
tremendous explosion.

The shock was heard in the faraway camp of William, and he knew that his
cavalry had arrived too late to avert the catastrophe he feared. They
had, indeed, just arrived within sight of the spot when the explosion
took place. They rode on at full speed, only to find the vast pile of
ruined woodwork blazing furiously. The Irish cavalry was seen in the
distance, leisurely retiring; but, although the English pursued for a
short time, the Irish easily evaded them in the darkness among the hills.
The whole of William's cavalry in camp were sent out, when the explosion
was felt, to endeavour to cut off the Irish horse; but Sarsfield was well
acquainted with the ground, and retired with his troops safely across the
Shannon, having struck a terrible blow against the designs of William.

The king, however, found that, in spite of the measures Sarsfield had
taken, two of the guns remained uninju