After the wagon was a receding dust-cloud on the trail, Charley went back up to the adobe, where Elsa was to stay on with her, and Ernest to sleep at night.

Outwardly life assumed its old routine. Gustav returned on the third day and reported that Dick was established at Doc Evans' house and that the Doc said "he'd have Dick about again in two or three weeks if no new complication set in." He also brought a letter from the Smithsonian man, Arlington, somewhat caustically deploring the fact that Roger had not been sufficiently interested to meet him and closing with the remark that he would not be in the neighborhood again for another six months. Gustav brought with him, too, the refilled drums of sulphur dioxide.

Roger handed the letter, without comment, to Ernest and went back into the engine house. He did not go up to the ranch for supper that evening as he had been doing, but the following morning which was Sunday, he appeared for breakfast. He was looking haggard and old but he greeted his friends cheerfully.

"Got any victuals for a broken down inventor?" he asked Charley.

She smiled faintly as she set a place for Roger at the table.

"You certainly look the part, Rog," said Ernest. "It's a good thing you've got friends with business heads."

"With what?" exclaimed Roger.

"Don't be cynical!" cried Elsa. "We sat up half the night working out a wonderful scheme for you. We—"

"Yes," Ernest interrupted eagerly, "we all went over the situation and we've made up our minds to a mode of action. You are such an impractical old chump, Rog! It's ridiculous for you to waste your time trying to make an engine out of a junk pile while the main idea of your invention, the real selling part, is neglected." He stopped to butter a biscuit.

Roger sipped his coffee and waited for Ernest to continue. "Now then, Elsa has a little money, enough to take me to Washington and back. It's her idea that I take that and go to see the Smithsonian people. There's not the slightest sense in your going. You're no salesman and I am. You remember it was I who landed Austin in the first place."

"I remember," said Roger quietly.

There was a long silence. Roger thought of the tiny food supply and of the months of experimentation that must go on before the Sun Plant would show efficiency.

"I hate to see Elsa putting money into this thing," he said slowly, "but at most I can always take a job and pay her back."

"Of course you can!" exclaimed Elsa.

"I know I can get money from the Smithsonian," said Ernest, "and we'll repay her at once."

Roger looked at Charley. "What do you advise?" he asked.

"I wouldn't hesitate for an instant," she replied. "Elsa feels just as I would—that the work must be finished."

"I know I can land the Smithsonian," reiterated Ernest, "and we'll repay Elsa at once."

"You needn't hurry," exclaimed Elsa. "As long as I have no money, I can't go home!"

Roger looked from Ernest to Elsa, then out the door across the desert to where the Sun Plant lay in the burning, quivering blue air.

"We'll try it out, Ern," he said. "You know how grateful I am to you both."

Ernest nodded. "Nobody's using the horses, so I'll drive in and leave the team at Hackett's. If Dick gets well before I come back he can drive himself out. Otherwise it will be waiting for me. Elsa, do you think you could fix up a clean collar and shirt for me?"

"If she can't, I can," offered Charley.

"Take anything you can find of mine," Roger's face was more cheerful than it had been for days. "I'll get the reports and drawings ready for you."

So, by the united efforts of the two households, Ernest was made ready for a flying trip to civilization. He was so happy and excited over the trip that he really lifted some of the sadness that had hung so heavily over the ranch house. After his departure, Gustav slept at the ranch, in order to do the chores while Roger remained at the Plant.

Ever since he had reached the desert Roger had been conducting heat tests and while he was able under perfectly controlled conditions to produce higher temperatures than those of the tables he had used for so many years, his average readings under the absorber glass were less than he had counted on. And so he was at work on a new type, low pressure engine, for which his average temperatures would produce ample heat.

Ernest took little stock in his new idea. "It may take fifty years to work it out," he had said the day he left for Washington. "Increase your absorption area and let it go at that. Better men than you have spent their lives on the low pressure idea and failed."

"I tell you," Roger had insisted, "that with a few changes of this present engine, I'll produce the low pressure engine of to-day."

"Well, go to it, old man! In the meantime, I'll fetch you some money so you can buy all the parts needed, and not have to continue your awful career of mountain brigand. The devilish thing about you inventors is that you putter so. My God, you drive me crazy! I do honestly believe that if it weren't for fear of starvation, you'd be puttering here for ten years."

"You're getting to be nothing better than a common scold, Ern," returned Roger with a laugh. "I'll be glad to get you out of the camp. Run along now and do your little errand."

With a routine established for caring for the two households, Roger bent all his splendid mind and energies on re-making the engine. Charley, coming to the camp one afternoon, as she or Elsa often did to cheer Roger's long day, watched him as he worked with infinite care to adjust a gauge he had taken apart.

"One of the many things that break me up," she said, "is that you missed the visit from the Smithsonian man."

"As it turns out," replied Roger, stoutly, "I didn't miss anything. I found when I got to work again that my safety device was inadequate and I've been all this time evolving a new one. If I'd run the engine as it was, I might have had a nasty blow-up and I've made one or two other changes, too, that are important."

"The engine doesn't look so very different to me," said Charley.

Roger chuckled. "Her whole insides have been made over really, by just a few changes. When Dean Erskine gets the new parts made and down here, I'll be O. K. I sent the design up to him when Ernest went in and some new parts ought to be here in a couple of weeks, now. I told Ern to have Hackett deliver them on arrival. It's too complicated to explain to you but I had another corking good idea the day that Dick went. I'm glad Arlington won't get here for six months."

Charley's eyes filled with sudden tears. "You're a lamb, Roger," she murmured.

"Where's Gustav?" asked Roger, quickly.

"He's puttering with the Lemon. If you need him, I'll go up for him."

"No, you won't. It seems to me that you need water on the alfalfa badly. The second field is getting pretty yellow."

Charley sighed. "I know it! Roger, that well just isn't adequate. I've told Dick so fifty times. He should have begun work on a driven well, long ago, but he's simply hipped on the powers of this present well. I think that the old thing is going dry."

"You do?" Roger's tone was startled. "Here, there's no hurry on this job. I'm just waiting really for the new parts. Let's go up and have a look at your whole water outfit."

They set off forthwith, the Lemon starting on its uneasy way, just as they reached the pumping shed.

"Something's wrong, certainly," exclaimed Roger, watching the stream of water that came from the pump. "There isn't half the usual stream there. Do you think the pump is all right, Gustav?"

"The pump is new and goot. The vater is low. Sometime, no vater it come at all. Then I vait for it to fill again."

"I don't understand it at all," said Charley. "There is plenty of water in this range. You see that old silver mine, up there?" pointing to an ancient dump on the mountainside back of the house. "Well, the lower level of that has a foot of water in it."

"How does it seem, stagnant?" asked Roger.

"I've never seen it," replied Charley. "Dick told me."

Roger lighted his pipe and took a few meditative puffs. "Charley, are you and Dick entirely broke?" he asked.

"We've got enough left of the turquoise money to grub stake us to the end of the year. Why, Roger?"

"Well, I think you've got to have a decent gasoline engine here, at once, if you're going to save that first crop."

"But I thought your plant—" Charley spoke carefully as if fearful of hurting Roger.

"So did I," he returned, a little bitterly. "But I've thought a good many things in my life that haven't come true."

"I'm very certain that this new engine of yours will do everything you expect of it." She smiled a little. "You remember poor old Mrs. von Minden said you were to found an empire."

Roger grinned. "She didn't know engineers!"

Charley's smile faded as she stood staring at the Lemon. "No, a new engine is out of the question. We—we have some bad debts that keep Hackett from giving us credit. We're counting on this first crop to clear part of that up."

"Then," said Roger decidedly, "there's just one thing to be done. We'll move the Sun Plant up here, now, while I'm waiting to complete the engine."

"The absorber and condenser! Oh, Roger man, the whole crop would be burned to a crisp while you did that! And only you and Gustav to do it, and the team is at Archer's."

Roger bit his pipe stem. "There must be a way," he insisted, doggedly. "There's got to be."

"Vy not make the vell, first," suggested Gustav who had been a silent auditor to the entire conversation. "If you don't get vater, a gut engine is no gut."

"Who's going to dig it?" asked Roger. "If it takes as long to get to water up here as it did at the Plant, you and I would be at it till October. No! I'm going to get help. I don't know how I'm going to get it, but it's going to be done. I could keep twenty men busy here for a month."

Charley sighed and Gustav shrugged his shoulders.

Roger relighted his pipe and went into a brown study. Gustav waited patiently for several moments, then left to do the evening chores. Charley sat on an empty box beside the pump watching now the stream that flowed over the field and now Roger's half closed eyes. Finally he emptied his pipe and rose.

"Didn't Elsa call supper?" he asked.

"Some time ago." Charley rose too. "But I didn't want to interrupt. Have you solved your troubles?"

"I don't know. But I've thought of something I'm going to try out. Wasn't that camp Felicia went to a permanent one?"

"Yes, in a way. The Indians come there again and again. But they won't work, Roger."

"Old Rabbit Tail works. Charley, take a little trip with me to-morrow. Let's see if my idea works."

"I'd like to, Roger. I haven't been away from sight of this adobe hut but twice in a year. Once, the night we found you, and once, the night you and I—"

"I know, poor old girl! Well, let's have a little picnic trip of our own to-morrow. We'll take Peter and some grub—get a dawn start and be back by sundown."

"Oh, I'd love it!" cried Charley, looking like Felicia with the sudden flash of joy in her eyes. "I'll put up the best lunch ever. Come along, Roger, do! Elsa will take our heads off."

Roger invited Elsa to accompany them on the mysterious trip, but Elsa refused to go.

"Dick will be back any day now," she said, "and I'm going to be here when he comes."

Charley made no reply to this but Roger frankly shrugged his shoulders. "I feel as if I never wanted to see him again. I'll be here at dawn, Charley. You can meet me at the corral, can't you, so's not to rout the others out too early?"

Charley agreed and dawn was just unfolding over the desert when she tied the grub pack to Peter's saddle. She waited for some time, sitting on the rock, her back against the corral, before Roger came. He appeared at last, just as the first rays of the sun shot over the mountains.

"Sorry to be late," he said, "but my gasoline's given out and I had to cook breakfast by hand, as it were, over some chips. Whew, it's going to be one hot day."

"I don't care how hot it is," replied Charley, recklessly. "I feel as I were being taken to the county fair, and I was almost too excited to sleep. Come along! I know the trail well."

It was a well beaten trail. The Indians had used it for countless generations in their search for pottery clay. It lifted zig-zag over the Coyote Range, giving at the crest this morning a superb view of distant peaks and of gold melting into blue infinities. It dropped zig-zag into canyons that were parched and cracked with late summer heat and lifted again to cross a peak whose top and sides had been blasted and left purple and gashed by an ancient volcano. Then once more it dropped gradually and gracefully into the canyon where the little spring mirrored the blue of the Arizona sky.

There were half a dozen Indian sun shelters near the spring, each a mere cat's claw and yucca thatch, supported on cedar posts. To Roger's surprise and gratification the Indians were at home. It was still early and they were at breakfast. With Peter trailing like a dog, Charley and Roger stopped a short distance from the camp.

Old Rabbit Tail, in his breech clout, squatted near a pot of simmering stew, now dipping in a long handled spoon and eating from it meditatively, now puffing at a yellow cigarette. Several squaws in dirty calico dresses, squatted near by awaiting their turn. Each shelter held a similar group, every one of which paused in breathless interest as the two whites approached.

Roger strode directly up to the old chief. "Good morning, Rabbit Tail!" he said.

Rabbit Tail grunted.

"I came up to have a talk with you," Roger went on, pulling out his pipe. "Sit down, Charley, this is going to be a regular pow-wow."

A tall Indian in the next shelter rose slowly and started quietly toward the back trail. "Hey! Qui-tha!" called Roger, sternly, "Come back here! I've something to say to you. The sheriff ought to have you. Call him, Rabbit Tail."

Rabbit Tail spoke in Hualapai and Qui-tha came slowly up to the old chief's shelter and dropping down beside him, lighted a cigarette. Charley, sitting on a rock at a little distance, chin in hand, arm on knee, shivered slightly in the broiling sun. Roger, who had learned much about Indians from Qui-tha, jerked his thumb at Charley.

"You know that white woman, Rabbit Tail?"

"Four years!" replied the chief.

"What kind of a woman is she—eh?"

"Good woman. My squaw have papoose one time in her 'dobe. Charley take care her all same she her sister. Heap good white squaw, Charley."

The squaw in question nodded and smiled at Charley, who smiled in return, a little sadly. Roger turned to Qui-tha.

"How about her brother, Dick Preble? You like him?"

Qui-tha, his brown face expressionless, nodded. "Yes! Most whites steal and lie. Dick he never steal or lie to Injun. Good man, except when drunk."

"Exactly," Roger clutched his pipe bowl firmly. "Did you tell 'em about the little girl—eh?"

Qui-tha looked up in honest surprise. "Tell what 'bout little girl?"

Roger turned to Rabbit Tail. "You haven't heard about what Qui-tha did to little girl?"

"Me no touch little girl," exclaimed Qui-tha, indignantly. "Have fight with Dick', no touch little girl. Like little girl, bring her home when she get lost up here."

"You know how Dick is a devil when he gets drunk?"

Qui-tha nodded.

"You knew that, yet you brought him a bottle of whiskey and got drunk with him and shot him in the leg when you fought."

The old chief turned inquiringly toward Qui-tha. Again Qui-tha nodded grimly.

"And you knew that the infernal drunken row you kicked up that night frightened the little girl so that she ran away into the desert where a rattle snake bit her and she died—died all alone at night, in the desert."

A look of complete horror rose in Qui-tha's eyes. "No!" he gasped.

"Ai! Ai! Ai!" cried the squaw who had given Felicia the pottery. "Poor little papoose! She was sweet, like her," pointing to Charley.

Then there was silence in the camp, all eyes turned on the old chief. Indians are great lovers of children. Their tenderness to them never fails, be they white or red or black.

"Dick heap sick?" asked old Rabbit Tail, finally.

"Yes, but he'll get well. He's at Doc Evans's house in Archer's."

"Did you tell the sheriff?" continued the chief.

"No," replied Roger. "Charley wouldn't let me."

Rabbit Tail turned to Charley. "Why?" he queried, laconically

Charley bit her lip. "The whites brought whiskey to the Indians in the first place," she said.

There was another silence. Then Roger began again. "Dick has been sick a long time now and he can't work much when he gets back. You know his alfalfa field?"

"Yes," said the chief.

"Well, Dick has been away and his water pump is no good and the alfalfa is dying. If we don't get water on it it will die. If it dies, then Charley will have much trouble, bad trouble. They owe Hackett much money because of Dick's drinking. So they can't get food unless they pay that money. They can't pay that money unless they sell much alfalfa. See?"

Qui-tha and Rabbit Tail both nodded.

"Now, I know you Indians don't believe in work. But if I can dig a big well for Charley and move my engine up to the adobe, I can get plenty of water on the alfalfa. It would take twenty Indians one week to move my plant. Rabbit Tail, you supply gangs sometimes for government work. Get Charley a gang for one week."

"You whites," said Rabbit Tail, "work heap hard for what you get—huh? If you live like Injun, no worry 'bout food, go out shoot 'em. No worry 'bout bed. Sleep in sand, huh?"

Roger nodded. "I think many times you're right, Rabbit Tail. But it's too late now. Whites have lived like this too many hundreds of years. They can't change to your ways any more than Indians can change to white ways."

Again there was a long pause before Rabbit Tail began once more.

"You know you whites kill many Injuns. Give Injun dirty sickness—kill Injun babies. Me—I see white take Injun baby by feet, smash head against rock. See Injun squaw belly cut out by white man. You know all that?"

Roger nodded. "The whites have been rotten to the Indians. I don't blame you for hating us. But how about Charley and the little girl?"

One of Qui-tha's squaws spoke. She had been educated at an Indian school.

"Charley showed me how to cure my baby of sore scalp and how to take care of him when he had croup. She lets me stay with her when he is sick or I am."

"She lets me use her sewing machine whenever I want it," spoke up a pretty young squaw in a red gingham dress.

"When old Chachee die," an elderly Indian woman looked from Charley to Rabbit Tail, "she die in Charley's house. Charley help sickness in her chest better'n medicine man."

Roger looked at Charley. He knew that she liked the Indians but she never had mentioned her good works to them.

The educated squaw spoke again. "I hate most white women. They treat us as if we were servants. But Charley treats us as if we were human beings like herself. And Felicia was a beautiful child."

"It's queer some of you have never been near Charley then, in her trouble," said Roger.

"The men have been working for months on the government dam at Bitter Peak. We were with them and just got here three days ago. Of course, Qui-tha didn't tell what little he knew. If the men won't help Charley, we women will. We could carry water to the field."

Qui-tha rose and walked over to Charley. "Qui-tha heap sorry. You give Qui-tha to sheriff."

Charley shook her head. "What good would that do?"

"All right then, Qui-tha go help one week, fix the alfalfa."

Old Rabbit Tail lighted another cigarette. "We come Monday, bring fifteen men, one week," he said.

"You know neither Roger nor I have any money, Rabbit Tail," explained Charley.

"Money no pay for blood. You good to Injuns. Now Injuns good to you."

Roger rose. "Thank you," he said simply. But Charley was too moved for words and as if she understood, one of the squaws put one hand on the girl's shoulder while she patted her cheek.

They clambered back to the top of the trail, without a word until the camp was out of sight, then Roger said with a half smile,

"You are some girl, Charley dear."

"And you are some boy, Roger."

"I? Why Charley, I'm just beginning to realize that I have gone through life with my eyes shut. The man with one idea misses most of life. I went up there with the intention of threatening a lot of savages. I've come away feeling as if I'd met a group of intelligent and kind hearted fellow humans."

"It was wonderful of them, wasn't it!" exclaimed Charley. "I had no idea they felt under obligations, to me. I certainly didn't want them to."

Roger nodded and looked at his watch. "It's only nine o'clock now. If it wasn't so frightfully hot and there were any place to go, I'd say let's continue our spree."

"Just beyond that strip of desert there," Charley pointed into the valley to the east, "there are some wonderful Indian inscriptions on some rocks around a spring. I've never seen them, but I've always wanted to and I know the trail. Dick has shown it to me."

"Let's try it," said Roger. "Peter, come on, you're getting fat and lazy. I believe it's about ten degrees hotter than usual."

It was an hour's climb down into the valley. It lost its level look on near inspection. In every direction a fine, powderlike sand lay in long undulating ridges. Neither rock nor cactus was to be seen. A faint wind was stirring and tiny eddies of sand rose against the sky.

"You see that peak, due east?" asked Charley. "Well, the spring is just at the foot of that in a little canyon. There's never any trail here at all, the sand drifts so."

"I'm glad we're heading for a spring," exclaimed Roger. "I know I can empty the gallon canteen by myself."

They started ahead, Roger leading, Peter following behind Charley. It was heavy slow walking. After perhaps an hour of it, during which conversation languished more and more, Charley said,

"I don't feel as eager minded as I did about Indian writings, do you?"

"Well," replied Roger, stopping to wipe the sand from his face and to grin at Charley. "I wasn't eager about the hieroglyphics to begin with. I haven't taken a girl for a walk for years and I thought this was my chance!"

"How is your enthusiasm for that standing up?" chuckled Charley.

Roger cleared his throat. "You see, it's like this—" he began, his eyes twinkling.

Charley interrupted by catching his arm. "Look, Roger! There's a sand storm coming!"

Roger looked up the desert to the north. The familiar gray veil of sand was plainly visible. "Lord!" he exclaimed. "We'd better start back at once."

"No, we're within a mile of the spring, now," said Charley. "We'd better get there as fast as we can. I do hope Gustav and Elsa will be all right. That poor new field of alfalfa!"

"Perhaps it won't be so bad in the other valley. Certainly this sand is going to try its best to suffocate us. Whew, there she comes!" as a cloud of sand enveloped them.

They paused long enough to adjust their bandannas across their faces, then started hurriedly on, Roger holding Charley by the hand and catching Peter's lead rope firmly. In ten minutes the peak toward which they were heading was obscured.

"Shall we stop or press on?" shouted Roger.

"Let Peter lead!" cried Charley. "If he stops, we'll stop."

Peter, shoved ahead of the little procession, did not hesitate. He dropped his head between his knees and moved very slowly, but none the less surely onward. The walking was almost incredibly difficult. The very desert underfoot seemed in motion. New ridges rose before their burning, half blinded eyes. The uproar was that of a hurricane roaring through a forest. Now Roger would stagger to his knees: now Charley. But Peter, lifting and planting his little feet gingerly and exactly, never stumbled. Panting, sweating, Roger after what seemed hours of this going halted Peter with some difficulty and putting his lips close to Charley's ear called, "Having a pleasant walk to the county fair, my dear?"

"Of its kind, it's perfect!" shrieked Charley in return and not to be outdone.

As if thoroughly disgusted by such persiflage, Peter brayed and started on without waiting to be urged. A moment later the footing became firmer and Peter led the way around a rock heap and buried his nose in a tiny pool that seemed thick with sand. Roger sighed with deep relief. He had seen the desert strike too often now to face her ugly moods with full equanimity.

There was no real shelter from the storm here. But it was vastly better than the open desert. They found a hollowed rock facing the spring, just big enough for the two of them to crouch with their backs against it. Although the sand sifted in on them constantly, they were at least away from the fury of the wind. There was water a-plenty at hand and they could bide their time. Peter established himself with his forefeet in the water, his tail to the storm and appeared to go to sleep.

For a time, Roger and Charley were glad to sit in silence, recovering their breath. But finally Roger stretched his cramped legs with a sigh.

"Charley, I find desert life just a bit strenuous," he said.

Charley wiped her face vigorously with her bandanna and nodded.

"So do I. But I like it. I think I must like the constant fight and the awful beauty. There's nothing else here."

"Have you anything in you but Anglo-Saxon blood?" asked Roger.

"No," replied Charley.

"That accounts for your loving it, I believe. The Anglo-Saxons are the trail makers for civilization. And by Jove, if any two people on earth are making trails it's you and Dick."

"You're Anglo-Saxon yourself. What is your work but trail making?"

"We aren't all trail makers!" Roger gave a half cynical chuckle. "You know I'm solving the labor question."

"With old Rabbit Tail's gang?"

"Hardly! Yet, by golly, Charley, I don't know but what I'm developing a typical labor situation down here. The Indian gang is working as a favor, you understand, and not from any necessity."

Charley laughed. "If it weren't for you inventors, we all could revert comfortably to Rabbit Tail's philosophy."

"It was to make that philosophy workable that started me inventing. That is, to give every man food and shelter with a minimum of work."

Once fairly launched, Roger gave Charley a rapid picture of the strike and the burning of the factory. When he had finished the two sat long in silence watching the gray veil that roared before them.

At last Charley shook her head. "It's a long trail from the old plow factory to the hieroglyphic spring, Roger."

"A long way," agreed Roger, "and I have no idea whether I'm helping or hindering labor. I only know now that my job is to make deserts bloom. Let labor go hang!"

Charley did not answer. She sat with her brown hands clasping her khaki knees, her hat pulled low over her eyes. Roger eyed her affectionately. It occurred to him that since Felicia's death, she had seemed more than ever like a fine intelligent boy. And yet he was honest enough to tell himself that there was infinitely more satisfaction in sitting in a hollowed rock with Charley than with any boy he had ever known. Suddenly Roger put his long arm across Charley's fine shoulders.

"Charley, you old dear!" he said. "I am mighty fond of you! You're the best man I know."

Charley said nothing for a moment. She reached up to clasp the hand that hung over her shoulder, then she turned to look into Roger's face and there was that in her eyes that held him speechless. There was in them Felicia's innocence and Felicia's eternal query. There was Charley's own sweetness and wistfulness, but back of these were burning depths of which Roger as yet had no understanding but they stirred him so profoundly that he paled beneath his tan.

"I'm glad you're fond of me, Roger. I'm fond of you." Charley's voice was gentle.

Roger's hand tightened on the girl's. "You are very beautiful," he said, a little breathlessly. "Even with your face all dust, and in khaki, you are beautiful."

"I am glad," replied Charley with a smile that showed her white teeth.

Roger did not speak again for a long time, but he did not release Charley's hand until she said, "Roger, the storm is going down."

Then he rose and stood staring at her until, smiling again, she said, "If you'll push your friend Peter out of the spring, I'll see if I can get clean water for us."