Clank! clank! clank! Jim felt the gears engage as he shifted the lever, and once more opened the throttle of the engine. Now he experienced a new and altogether delightful sensation; for the huge mass of machinery to which the cab was bolted, and which was situated on the front of the heavy truck carrying the whole apparatus, swung round easily, the loaded bucket well in front and overhead. Harry grinned: it amused him to watch the delight on his pupil's face. But this was not the moment for allowing his attention to become distracted. He kept a careful eye on the bucket, and, a moment later, just as it began to swing over the dirt truck placed on the side track, he pulled a rope, and with a loud clatter the bottom of the bucket banged open and the dirt fell into the truck. "Stop her!" he shouted, and Jim at once closed his throttle. "This is the boy that works the shutter for us. See here; pull it and give her steam. Watch those two arms to which the bottom of the bucket are bolted. This here gear just overhead works 'em and closes them over the trigger. Gee! If you ain't working this here like an old hand. Now watch it. That bucket's closed, and you've always to remember to close it afore you swing the machine back again to its work, 'cos the edge of the bottom comes low down and would foul the truck. That'd mean a bust up. Now, round with her. Stop her; get a hold of the brake lever and let her drop." Confused at first, because of the multiplicity of movements, in an hour Jim was quite at home with the machine. True, he made errors; for instance, he forgot that very important movement to close the bucket, and, as a consequence, though he missed the side of the truck he nearly ripped off the head from a negro. But Harry was there to supervise, and a quick movement on his part arrested the machine. "Hi! What fo you gwine kill me, yo?" shouted the negro, who had been untouched, as it happened. "Yo take care ob that great big playting ob yours. Not here to dig niggers. Not like hab de head knocked off." Harry roared. "It's only Joe," he shouted. "He's been as near a blow afore now, and loves to make the most of it. See here, Joe," he bellowed, "I ain't a-goin' to have my machine broken against that 'ere hard head of yours. I'll have to be warning the foreman overseer to shunt yer." That brought a grin from the negro. He showed his teeth, and shook his fist at Harry; but Jim knew his meaning well enough. The big fellow was just like the rest of his people--just a big, strong, healthy baby, who saw the fun in everything, and, if there were no fun, manufactured it promptly. "I's gwine to break yo into little pieces," he said, clambering on to the cab and poking his face within an inch of Harry's. "Yo say I hab hard head? Lummy! Me hab hard fist as well." "Git out!" shouted Harry, striking at him with the slack end of the rope that commanded the bucket trigger.