“Mixer last!” snapped the girl, plugging in and ringing her call at the same time. “I’ll see if he’s still there!”

“Meantime, where’s Mr. Taylor? He’d help—”

“Can’t get him—gone to Las Cruces. Yes, hello, Mixer? The Chief? Gone? Yes, yes! Where? North end spillway! Right! ’Bye.” She pulled out the plug and said to Jerry, “Started for spillway ten minutes ago. No phone there yet. Take fifteen minutes get messenger there—can you wait?”

“No,” said Jerry. “Mr. Rutherford, my chief, wants him. Wall of auxiliary spillway this side of the river giving way—will flood all the buttress excavation. We’re shoring it, but Mr. Rutherford wants the Chief and in a hurry. I’m off but I’m afraid I’ll get him too late! If he calls up send him to Mr. Rutherford at once!” With this Jerry shot out of the office and down the hill, evidently planning to make his legs take him to the Chief.

Inside, Bob had been listening with wide open ears and his mind pictured the scene Jerry had left to find Mr. Whitney and filled out the holes the winded boy had left in his description. He knew the auxiliary spillway and the harm it could do if it should fail to carry its burden. It was a temporary affair of wood to be used only until a system of drains could be built to take care of the excess water that collected below the coffer dam. His mind’s eye saw Rutherford and Jerry at the dangerous place: Rutherford, young and inexperienced, doing what he could to avert disaster, but rattled, probably badly so. He wanted Mr. Whitney or somebody with practical knowledge and he had sent Jerry off to bring help. All Bob could do was to hope that the wall would hold.

Reluctantly he started to take up his dreary work but on the way to the board, his eyes glanced through the window and rested on a grab bucket that was speeding through the air. For a second the sight meant nothing special to him, then suddenly it brought him to his feet. Without a word to the other draughtsmen he dashed out of the room, not waiting to snatch his cap.

A plan had come to him in a flash. Whitney was needed and needed in a hurry. He was on the other side of the river valley at the head of the spillway. The opposite cableway tower over there was near this spot—if the buckets could go over, couldn’t he? He’d try anyway!

With all the speed he could muster he ran towards the cable tower, thanking his stars that the control station was on this side of the river, and that he knew one of the lever men. It was this fellow’s job to dispatch the buckets and hoist and lower them.

“Trouble below, Billy!” gasped Bob as he came to the shed that protected the operator from the rays of the sun. “Need the Big Boss. He’s over at the spillway. Shoot me over?”

“’Gainst rules, son,” was the man’s answer, pulling a lever which made a great bucket shoot up from the depths.