The Ranger would start a search for them in the DeHaviland, once the fire was under better control. The Forest Service finds its air service as useful in keeping track of law breakers as of fires. It would be an extraordinary thing if the careless camper should escape detection, for the air men can spy them out as easily as anything. But the fire still ate angrily through the timber, and would spread in all directions if left to itself. Fire fighting is sometimes a matter of weeks.
It was a dry summer, and all up and down the Sierras, the Rangers were kept busy fighting the fires that would break out from one cause or another. The Service ’planes were all busy.
The five campers were back at fire-fighting headquarters,—and Norris too,—when Ace had an idea. He and Ted would go in search of the Mexicans in his little Spanish ’plane. Would Radcliffe let them off the fire-fighting? He would, though he could not give official sanction to their plan. It was enough. The two boys were off before he could change his mind,—to Norris’s slight uneasiness and Pedro’s envy. (But Pedro was subject to altitude sickness.)
Sometime, Norris had promised Ted, they would go back into the cave and look for his fossil. But that could wait.
All that afternoon the two boys curveted over the surrounding scenery,—careful to keep their distance from the whirlwind of fire-heated air, for they were flying low. The most minute search failed to reveal the fire setters, but Ace only set his jaw the more determinedly.
They returned to sleep twelve hours at a stretch. Aviation is the best cure yet for insomnia, and neither Ace nor Ted had ever been troubled with that malady. The next day they flew farther, carrying with them an emergency camp kit. They landed about every two hours, rested awhile, and finally went into camp about four in the afternoon, intending to take a look in the night to see if the fugitives would betray themselves by a bon-fire. They camped in a meadow where they had seen something like smoke arising. This proved to be steam from a hot spring, and they thought with longing how fine their chilled bones would feel in a good hot bath. But the spring water came too hot. (If they had had eggs, they could have cooked them in it.)
Then it occurred to them to dig a little trench, line it with stones, and carry the spring water by the folding canvas pailful to fill it. It would quickly cool to the right temperature. The scheme worked wonderfully.
The water had a strong mineral taste, not altogether agreeable, but its effect on aching bones was wonderful. A flint arrowhead buried in the soil they excavated told its tale of Indians, who must have valued the spring and fought for its possession against covetous tribes.
“What makes these hot springs, anyway?” asked Ted. “Have you had that yet in your geology?”
“Yes, but you’ll understand better when Norris tells us the story he’s promised about the formation of the earth. I’m no professor.” And he turned a former laugh on Ted. “Tell you what, Old Top, once we get these fire bugs located for our Uncle Sammy, what say we fly up and have a look at Lassen volcano before I send the ’plane back?”