“Well, fellows, what’d you do with yourselves while I was away? Must have been pretty up at the , wasn’t it?” It was Mr. Whitney talking. He had told them that his trip to Washington had been a great success. They had sent for him to put him in charge of finishing up the big Rio Grande project.  
“That’s great!” said Jerry, who had experience enough to know that a great honor had been conferred on his Chief. The Rio Grande project was the biggest thing the Service had yet attempted and to be in charge of it was equivalent to a high .
 
Bob Hazard knew from Jerry’s spontaneous outburst that Mr. Whitney was to be congratulated, so he made a little speech.
 
“Thanks, fellows, thanks,” laughed the Chief. “It will be fine for all of us. But that’s enough of my news—what have you chaps been up to? Been bored?”
 
“Oh, we found plenty to do,” said Jerry.
 
“At the Canyon?” asked Mr. Whitney. “I don’t see how you could. It is a pretty place, if you have to be there long.”
 
“But we weren’t at the Canyon,” put in Bob.
 
“So? You surprise me. But wherever you were, I bet you were in . Just from the look of you two, I can see that you were up to some devilment. Besides, you’re almost boiling over with the desire to tell me about it. Come on, out with it.”
 
“We went through the Canyon,” said Jerry calmly.
 
This news made Steve Whitney jump out of his chair. “What!” he cried. “You went through the Labyrinth? You’re joking.”
 
“Not at all,” said Bob calmly. “We got tired of doing nothing and we went up the Green River and went through it.”
 
“But—but nobody’s ever gone through alive,” the man. “I’ve always wanted to try it myself but never found the chance. How did you do it?”
 
“Boat partly and swimming,” returned Jerry, anxious to state the exact facts.
 
“But didn’t you have an awful time?”
 
“Oh, it wasn’t so bad,” said Bob. “Once or twice we had a little trouble but all in all it was just fun. And the reason we went was because Jerry thought there might possibly be a project there.”
 
The calm way in which the boys announced their forced Whiskers to believe what at first glance seemed to be a .
 
“I’m sure proud of you two,” he said warmly. “But I ought not to be. It was a foolhardy thing to do and if you had asked my permission I certainly would not have given it.” But as he reproved them his eyes with the pride he felt. “I want to hear all about it, but first tell me, did you find a place where you think a dam could be built? There is a wonderful valley out there ready to spring into life if we only could get water to it.”
 
“You bet we found a place,” said Jerry. “The dam is already half built by nature. Besides, I feel sure a road can be made down from the top of the canyon.”
 
“That’s great!” said Steve Whitney. “Now go ahead and spin me the whole yarn.”
 
Jerry let Bob tell of their adventure, putting in a word here and there. But when it came to the part where Bob had saved his life after dropping over the waterfall, he took the in his own hands and in spite of Bob’s protests, told the Chief the whole story of the rescue.
 
When they had finished, Mr. Whitney was very much excited. “We’ll have to make a report of your find to Washington at once and, if possible, get a bill brought up in the next Congress to us to make a preliminary survey. We can do it next summer.”
 
That their discovery had a good chance of being acted upon, was a big measure of reward to the two boys. Mr. Whitney’s interest seemed to settle the matter.
 
“You—you think Congress will authorize it?” ventured Bob, just to make sure.
 
“They will have to!” was the confident reply. “I’ll draw up a report the moment we strike camp! But now we’ll have to run for our train. I’ve been so interested, I forgot the time.”
 
The trip passed quickly for Bob and his Chief. Mr. Whitney was on his way to the biggest job he had yet tackled, and Bob would taste for the first time the flavor of the work he felt he most wanted to do. To Jerry, however, the train was only bringing him to a new spell of hard .
 
When at last the cars stopped, they found a car waiting, into which the three piled. Once under way, Bob asked Mr. Whitney, “Doesn’t the railroad go into the camp? It seems to me it must be pretty heavy hauling all the big from here across the desert.”
 
“A railroad goes to the job all right, Bob, but it’s meant for freight and a train runs only three times a week. The line was built by the Service and belongs to the Government. We’ve come the wrong day to catch that train.”
 
“I see. And does the Service build other things besides dams and railroads?”
 
“Surely! On a job like this so far away from any regular transportation line the Service has to construct all the necessities of life—and some luxuries. It built the town that we’ll be coming to shortly, put in the electric light system, a school and a hospital. In some places we’ve even built a motion picture theatre to keep the men satisfied. Probably there’s one on this job. When I was up here last they were planning it. I bet you never thought Uncle Sam was in the amusement business.”
 
Bob laughed. “There sure must be a lot of men working up there.”
 
“It’s a young city. But here we are.”
 
The road had been climbing and now it topped the of the hill. Before their eyes lay a wonderful . To the north, the wide valley of the river stretched into the distance, a band of green and gold, flanked on each side by the glowing desert. Immediately below them the peaceful face of nature was broken.
 
It was the place where the dam was to be built—where already part of it was built. From the height from which they looked the network of cables and railroad tracks and rushing ant-like figures, seemed a confused without a sense of direction. But as the car coasted down the well-made road—also constructed by the Government, Bob learned later—the jumble became clearer. The cables, extending from one side of the hill to the other, carried buckets which rushed to and fro. These were lowered and seemingly by chance. The engines pulled cars of rock to the crusher and backed away for new loads. The men now showed themselves as workers, the directing units, and their rushing about was merely carrying out their part of the great work.
 
Finally the car came to a stop before a large two-story house. The boys followed Mr. Whitney inside. “This is the Quarter-house,” Mr. Whitney explained as they went in. “They have rooms here for the engineering force and it is also used as a hotel if any guests happen to come along. I’ll see if you boys can be put up here until we can find permanent quarters for you.”
 
Hardly were they over the threshhold, before a short, stocky, man came up to them. He rushed up to Whitney with outstretched hands and said, “I certainly am glad to see you, Whitney. Adams has been gone two weeks and I have been expecting you almost any day. I couldn’t get down to meet you at the station, as they needed me over at the spillway. Little matter of extra shoring. It’s all right now.”
 
The Chief shook the other man’s hand warmly. “You’re staying on, aren’t you, Taylor?” And when the other nodded his , he continued, “I’m glad! Couldn’t have better luck! I was hoping that you would stick as my assistant. My first job for you is to find jobs for a couple of rodmen I brought along with me. Here, boys, I want to introduce you to Mr. Taylor, the assistant engineer and therefore your boss.”
 
Taylor had flushed at Mr. Whitney’s words of confidence. It was easy to see that he would probably always be an assistant, never a full-fledged chief. He was the kind of man who could execute orders but when left with the responsibility of making decisions for himself, was likely to become and upset. He took refuge in the about the boys.
 
“There’ll be plenty of work for ’em. It happens we’re a little short on rodmen just now. But about sleeping quarters—I’ve got your house ready for you, Whitney, and as soon as your dunnage comes along you can move right in,” he said.
 
“That’s fine,” returned Whitney. “But the boys—”
 
“Oh, there’s room here for the time being. We can see about something else later. But you must be . Come along to my . It’s about supper time. You come too, fellows. The regular mess is over.”
 
Both Bob and Jerry were overjoyed at the invitation. The long trip had made them hungry and they rather wondered where their supper would come from. Mr. Taylor waited until they had taken their suit cases up to the room that had been assigned them and then the little group walked up the street to the cottage that was the assistant engineer’s. His wife, a pleasant-faced woman, welcomed them and seemed especially pleased to see Whitney. Bob realized that his friend evidently was a great favorite and had made many friends during his years in the Service.
 
Mrs. Taylor had prepared what seemed to Bob an especially fine supper, considering that they were miles away from civilization. During a in the conversation he mentioned it. She was much pleased.
 
“Oh, New York has very little on us up here,” she said. “What with a cold storage plant and an ice factory, we don’t want for anything.”
 
It was so. In this frontier camp practically all the comforts that the civilization of a city could give were present: electric lights, ice, excellent stores—and the movie theatre. It was like transplanting a little corner of a city.
 
After supper they went out on the porch from which could be seen the works. Dusk had come during the meal and already the stars shone pale in the sky. Down at their feet vague outlines of the could be seen, the darker shadows marking their extent. Down to the left was a cluster of bright lights.
 
“What is that?” Bob asked.
 
“The town,” was the answer; “the mechanics’ houses and the houses for the Mexican . The only people who live up here on the hill are the engineers and executives.”
 
When the men got their cigars lighted they began to talk. Whitney was of course anxious to know what the situation was on the job he was to tackle in the morning. If the laborers were satisfied, how the work was progressing, and a thousand and one other things he needed to know bubbled . The assistant engineer was a veritable mine of information. Practically every question was answered without a moment’s . Bob was to sit and listen, drinking in all the information he could. This was the Service and to-morrow would see him taking an active part in the work.