There were no signs of the "Meteor." Acting upon Dacres' request to his chief the airship had put a safe distance between herself and the capital. The wind had fallen, the sky was cloudless and unbroken. Had the "Meteor" remained she would have inevitably been sighted by the garrison of Naocuanha and Zaypuru's suspicions would have been aroused.
Just before eight a telephone message was received at the Cavarale stating that the president would arrive half an hour earlier than he had previously arranged.
His object in visiting Gerald Whittinghame was a crafty one. He knew the value of the captive Englishman's technical skill; he totally underestimated his sense of honour. Reno Durango having, from some cause for the present unknown, failed him, Zaypuru bethought himself of Gerald Whittinghame.
His plan was to offer the Englishman his liberty and a huge sum of money if he would take charge of the aerial defences of the city of Naocuanha. He remembered that under President San Bonetta's regime Gerald Whittinghame had brought out an aerial torpedo—a monoplane carrying a heavy charge of guncotton—which could be electrically controlled by an operator on the ground. The device passed the severe tests imposed upon it with the greatest ease. Then came the revolution that caused San Bonetta to lose his life and Gerald Whittinghame his liberty. The knowledge, unlike that which resulted in the construction of the "Libertad," remained with the inventors, and hitherto threats and promises alike had failed to extort the priceless secret.
"Troops on the move, sir," announced one of "Meteor's" crew who had been posted to supplement the Valderian sentries on the wall of the Cavarale.
Dacres and Gerald ascended as quickly as possible, then taking cover behind the breastwork, used their binoculars through one of the embrasures. "That's Zaypuru's bodyguard right enough," said Vaughan's brother. "He doesn't go far without that escort."
"Quite enough to set up a fairly good fight if they've any pluck," remarked Dacres. "I don't think we ought to let the whole party into the courtyard."
"Yet I don't see how we can prevent them without arousing suspicion."
"I do," said Dacres. "You've forgotten the bridge across the dry moat. We'll fix a detonator, sufficient to bring the whole concern down without doing very much harm to the President's bodyguard. We'll have to hurry, for there's precious little time."
"But we haven't a battery," objected Gerald.