"Who's he?" demanded Joe, nodding at Jim, and suddenly changing the conversation. "Him? Why, Jim, of course. Saved Mr. Barton." "Den I knows him." To Jim's astonishment the negro stretched out a hand and shook his eagerly. Then he explained the situation. "Know Tom and Sam," he said. "Dey down here now, seein' tings. I show dem round. Tom mighty impressed: he tink yo work de digger better'n Harry." That brought an exclamation from the latter, while Joe jumped down from the machine just in time to escape the swing of the rope. But his words were true; close beside the digger were Tom and Sam. "By de poker, but yo run him well!" shouted Tom. "Me's watched yo dis last half-hour. Seems to Tom as ef yo soon have a job in the diggin'." To the huge fellow everything that Jim did was well done, everything he attempted was sure to be accomplished; and never for one moment did he tire of watching his hero. But Jim had his lesson to learn, and for another hour held to the work. By that time he had filled a whole spoil train, and had watched another shunted into position. "Ready to fill like the last," said Harry. "That's the proposition that jest beat us at first. There wasn't enough trucks nor locomotives to begin with, and not enough tracks, so these fine diggers wasted half their time; but we've fixed it a while since. Soon as a train's loaded it's pulled back, while an empty spoil train crosses the switches behind. That comes over another switch just behind the digger, and so right on alongside, the last truck just in position for loading, the first 'way ahead. Then, as you've seen for yourself, we move along, a few inches after every dig, filling the trucks as we go." "And then?" asked Jim. "What happens? Where is the dirt taken? Who unloads the trucks?" "Gee! You are a chap fer questions. Where does it go? Away up there, at the far end of the river gully, where the Lake of Gatun'll be, there's a sight more dirt than this being taken from the isthmus. Some of that's being dumped at the dam just away over our heads; some of it's being emptied outside Panama, filling up a swamp through which the canal will run. Reckon there won't be swamps when we're done. There'll be good hard ground, and houses'll be built on a spot where there's fever nowadays. We're using dirt at this end in the same way; but you was asking about the dumping?" Jim nodded, and looked at the spoil train being hauled away. "The gangs of niggers do it, I guess," he said. "But it must take longer than the loading by a long way; at least that's what one would imagine."