The man at the helm and the man with the lead-line fell backwards into the boat. Ayrton's and Pencroft's balls had struck them both at the same moment.

Almost immediately a louder report was heard, a cloud of smoke issued from the brig's side, and a ball, striking the summit of the rock which sheltered Ayrton and Pencroft, made it fly in splinters, but the two marksmen remained unhurt.

Horrible imprecations burst from the boat, which immediately continued its way. The man who had been at the tiller was replaced by one of his comrades, and the oars were rapidly plunged into the water. However, instead of returning on board as might have been expected, the boat coasted along the islet, so as to round its southern point. The pirates pulled vigorously at their oars that they might get out of range of the bullets.

They advanced to within five cables-lengths of that part of the shore terminated by Flotsam Point, and after having rounded it in a semicircular line, still protected by the brig's guns, they proceeded towards the mouth of the Mercy.

Their evident intention was to penetrate into the channel, and cut off the colonists posted on the islet, in such a way, that whatever their number might be, being placed between the fire from the boat and the fire from the brig, they would find themselves in a very disadvantageous position.

A quarter of an hour passed while the boat advanced in this direction. Absolute silence, perfect calm reigned in the air and on the water.

Pencroft and Ayrton, although they knew they ran the risk of being cut off, had not left their post, both that they did not wish to show themselves as yet to their assailants, and expose themselves to the "Speedy's" guns, and that they relied on Neb and Gideon Spilett, watching at the mouth of the river, and on Cyrus Harding and Herbert, in ambush among the rocks at the Chimneys.

Twenty minutes after the first shots were fired, the boat was less than two cables-lengths off the Mercy. As the tide was beginning to rise with its accustomed violence, caused by the narrowness of the straits, the pirates were drawn towards the river, and it was only by dint of hard rowing that they were able to keep in the middle of the channel. But, as they were passing within good range of the mouth of the Mercy, two balls saluted them, and two more of their number were laid in the bottom of the boat. Neb and Spilett had not missed their aim.

The brig immediately sent a second ball on the post betrayed by the smoke, but without any other result than that of splintering the rock.

The boat now contained only three able men. Carried on by the current, it shot through the channel with the rapidity of an arrow, passed before Harding and Herbert, who, not thinking it within range, withheld their fire, then, rounding the northern point of the islet with the two remaining oars, they pulled towards the brig.

Hitherto the settlers had nothing to complain of. Their adversaries had certainly had the worst of it. The latter already counted four men seriously wounded if not dead; they, on the contrary, unwounded, had not missed a shot. If the pirates continued to attack them in this way, if they renewed their attempt to land by means of a boat, they could be destroyed one by one.

It was now seen how advantageous the engineer's arrangements had been. The pirates would think that they had to deal with numerous and well-armed adversaries, whom they could not easily get the better of.

Half an hour passed before the boat, having to pull against the current, could get alongside the "Speedy." Frightful cries were heard when they returned on board with the wounded, and two or three guns were fired with no results.

But now about a dozen other convicts, maddened with rage, and possibly by the effect of the evening's potations, threw themselves into the boat. A second boat was also lowered, in which eight men took their places, and while the first pulled straight for the islet, to dislodge the colonists from thence the second maneuvered so as to force the entrance of the Mercy.