“But what?” insisted the Spanish boy. But had he not guessed it! Of course he would remain behind to keep track of the desperadoes.
But how could Ted start with the ground so hot? He would have to wait awhile, then make up for lost time by break-neck riding.
So be it. They were hungry now, and ate the ration of tinned corned beef and hardtack from their pockets. Ted also fed the horse some hardtack, and brought him several hatfuls of water from the spring,—scorching his soles as he crossed the charred ground.
Pedro propped his tired body in a sitting posture with one ear cocked for the conversation within. Ted flung himself flat on his back in the smoky gloom, which obscured even the light of the moon. He was mentally exploring that cave,—remembering what Norris had once told them of the region and wondering into what limed recesses the Mexicans were likely to retire when capture threatened. That the cave had its depths he felt assured by their having so suddenly appeared with their torches. And what could Pedro do if they tried to leave before help came?—My, but he must ride! Three such incendiaries loose in those dry forests, and there would be no end to the harm they could do!
The limestone of which these caves were formed,—sediment of the shells of myriads of sea creatures,—had been deposited in the primeval ocean that once flowed over that whole region from the Gulf of California. Uplifted by contractions of the earth crust, it had been cut as the surrounding granite could not have been by the percolating rains and streams, flowing along the cracks of the uplift.
This cave was probably a network of water-worn passage-ways extending no telling how far underneath the ridge. There were reputed to be caves almost as large as Mammoth in these unexplored recesses of the Southern Sierras. Could this be one of them, or was it just a two- or three-cavern affair, he wondered? On that depended a very great deal of their success in the coming capture, for once entrenched within these labyrinthian caves, the Mexicans could hold them at bay until they had made good their get-away. It had been so, he had been told by military men, in chasing Mexicans over the border.
Perhaps there were other caves in the region. Where, indeed, had these men secreted themselves while the fire had raged in a semi-circle about them? In a cave, the air would be damp and cool, no matter what was going on outside, and they could have been genuinely comfortable with the inferno raging over their very heads. Unless, of course, the smoke suffocated them! That would all depend on the air passages that fed their particular cavern. Some of those caves across the Mexican border were miles in extent, and had exits galore.
Pondering the pendant stalactites that had gleamed like onyx in the firelight, he pictured the water percolating drop by drop through the limestone crevices, dissolving the lime and forming the stalactites a drop at a time through the years. How wonderful it was! He wished he too might study. Perhaps, if he could make a go of his mother’s fruit ranch?—He was half asleep. He roused himself by trying to recall what it was that Norris had told them about stalactites.
The rain water, charged with the carbonic acid gas of the atmosphere, seeps in from the surface and falls drop by drop. Each slow drop remains long enough upon the ceiling to deposit some of its dissolved lime in a ring to which the next succeeding drop adds another layer.
In time this ring lengthens into a pipe-stem of soft lime. It fills and crystallizes, thickens and elongates, as the constant drip, evaporating from the outside, deposits more and more of the lime. Thus these stone icicles are formed, sometimes an inch a year.