’Because there was no help for it. My followers were far away, and we had to do the best we could. Here it is we who are going out to make an attack, and’—— ’And we are going to join and help all we can,’ Jack declared stoutly. ’Your quarrel is ours. Please say no more, but give us our share of your arms—or would you prefer that we should trust to our pistols?’ ’Better have our usual weapons, if you are determined, and keep your own as a reserve,’ Alondra decided. And so it was settled; and not only the two chums, but Clinch and Reid—who had, during their visit, learned the use of the Martian weapons—were duly fitted out after the fashion of the rest of Ivanta’s following. As they proceeded, the exact direction and other necessary instructions were signalled from the leading yacht by means of curious devices in coloured points of light, which appeared from time to time like tiny coloured fireworks upon the masts. After a run of a couple of hours, a halt was called, and Alondra was signalled to come alongside the king’s yacht. One moon had set, and the other had become obscured by clouds. The landscape was now in shadow, and the squadron was almost invisible from below; for, save the occasional twinkling of the signals, the flying craft showed no lights. ’The place we are going to attack,’ Ivanta explained, when the leaders had been assembled in his cabin, ’may be, as our friend Fumenta declares, weakly held so far as the number of the garrison is concerned, but in other respects it is a most difficult place to assail. No one should know this better than I,’ he continued, a little bitterly, ’because I myself designed the fortress and its defences. I knew that it lay in a very exposed region, where it would be difficult to keep a large garrison, and where a surprise might at any time be attempted. So I did everything that my ingenuity could devise to render it practically impregnable.’ ’I know all that to be true, sir,’ observed Fumenta quietly. ’It is neither more nor less than a great cavern—or, rather, series of caverns—in the side of a precipitous mountain,’ Ivanta went on. ’One can neither approach it nor leave it except by flying-machine. There is no path, no ledge, which anything but a fly could cling to. There is only one defensive wall—that which closes the outer side of the caverns—and this has been so built in as to resemble a continuation of the precipice. One cannot tell by looking which is the natural rock and which is the artificial stone wall. There are gates, or rather iron doors, and these are specially defended by being connected with the electric storage batteries. When the current is turned on—as is supposed always to be the case at night, or when the doors are not in actual use—it is death to any one who touches them.’ ’All that I know, oh king!’ said Fumenta. ’There is also an underground waterfall—an immense body of water ever tumbling through the great caverns.’