"They will not be joined by Xuarez, Don Miguel. When the rebels arrive, they will find no savage allies under the walls of Tlatonac." "If it could be so, it would be well. But how, Señor, do you propose to make this savage army vanish without a blow?" "By means of the Chalchuih Tlatonac." "I do not understand, mi amigo. Explain, if you will be so gracious. I am all attention." Jack began to explain without further preamble. "Observe, Excelencia," he said slowly, so that Don Miguel could have no difficulty in following his reasons, "It is now noon--this night, if I mistake not, the Indian army will come to Tlatonac----" "Bueno!" interrupted Cocom, nodding his head like a mandarin, "I have heard this thing spoken with many tongues. Your messenger, Excelencia, will confirm what I say. The Indian army will march this night for Tlatonac. At dawn will you see them encamped round the walls." "Proceed, Don Juan," said the President, gravely. "As you can see, Señor Maraquando," pursued Jack, emphasising his remarks with his finger, "the savages will not arrive till night, so as it is now but noon, we will have time to make ready for their arrival." "Dios! You said make no preparations!" "Not hostile preparations! No, Señor; listen, I pray you. We have the Chalchuih Tlatonac, the properties of which are regarded with superstitious reverence by the Indians. What the opal commands they will do. When it glows red, they prepare for war. Let an azure ray shine, and they know that the god commands peace, and, at whatever cost, will lay down their arms." "How is this done, this glowing of red, of blue?" "I will explain, Señor. In the hidden city I saw it. The opal hung by a golden thread before the shrine of Huitzilopochtli, and this thread was twisted in a certain way by the priests. By careful calculation, they could tell how far it would untwist, so that the opal stone depended motionless, showing the colour they wished. If they desired war, the red side of the stone revealed itself--if peace the blue. To prophesy plenty, the yellow ray came to the front, and so on with all the tints." "Then you say, Don Juan, that if these Indians saw the opal glowing blue, they would lay down their arms?" "Assuredly, Señor! and withdraw at once to Totatzine, leaving Xuarez to meet the forces of the Junta alone. If the stone glows blue, they know it is the will of the god that they should not fight." Don Miguel smiled incredulously. "I doubt, Señor, whether these warriors, flushed with the sacking of Puebla de los Naranjos and Chichimec would obey the stone now, even though it glowed blue and thus proclaimed peace."