Presently, a smudge of brown smoke soaring above the horizon broad on the port bow showed that the unsuspecting quarry was approaching; and a minute or two later her masts, fine as spiders' webs, began to rise against the warm, golden glow of the western sky, then her funnel appeared, and finally her bridge and chart-house--appearing as completely detached and isolated objects in the rarefied atmosphere-- suddenly showed themselves on the horizon, alternately appearing and disappearing with the rise and fall of the ship over the swell. Then Milsom rang down to the engine-room for half speed; and a little later, when the _Maranon_ was hull-up and the two vessels were closing fast, he ordered the forward port twelve-pound quick-firer to be loaded with a blank charge. Then, when the two craft were about a mile apart, he ordered the Cuban flag to 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.