be run up to the main gaff-end, and the gun to
be fired as a polite invitation to the other craft to heave-to, at the
same time stopping his own engines.

Apparently the skipper of the _Maranon_ did not know what to make of it;
for, beyond hoisting Spanish colours, he took no notice of the summons,
making no attempt to stop his engines.

"Mr Perkins," shouted Milsom, "just heave a shot across that chap's
fore-foot, will ye? and we will see whether he understands that
language. But for goodness' sake take care that you don't hit him by
mistake. We don't want to have the destruction of that vessel on our
consciences."

Bang! barked the twelve-pounder for the second time, and there was now a
vicious tone in the bark which said unmistakably that the gun was
shotted; while, if anybody on board the _Maranon_ had any doubt about
it, that doubt was a moment later dispelled by the sudden up-leaping of
a fountain of foam some twenty fathoms ahead of the vessel. That proved
conclusively that the mysterious gunboat flying the Cuban flag was in no
humour to be trifled with; and the Spanish captain, objurgating
vehemently, rang down for his engines to stop. Thereupon the "gunboat",
which by this time had swung round, presenting a view of her stern, with
the name _Libertad_ emblazoned upon it in gold letters, lowered a boat,
into which four seamen, a coxswain, and a big, black-bearded officer
dropped. When the frail craft, propelled by the four sturdy oarsmen,
pushed off, and went dancing, light as an empty eggshell, over the
purple swell toward the convict ship, the officers on the bridge of
which did not fail to note that the crew of the stranger had carefully
trained two long, beautifully polished guns and a couple of Maxims on
them, "as a gentle hint that there was to be no nonsense," as Milsom put
it.

Meanwhile, the crew of the _Maranon_, seeing the boat approaching,
busied themselves with the task of lowering their side ladder, which
they got into position just as the boat dashed alongside and her crew
tossed their oars. Although the swell was by no means high, the convict
ship rolled heavily upon it as soon as she lost her way, and Jack had to
watch his opportunity to spring out of the boat on to the ladder without
accident; but he managed it cleverly, and the next moment stood upon the
deck of the _Maranon_, where he found the captain of the ship and his
chief officer awaiting him. As he stepped in through the gang