"Specks there's been a breakdown, or something of that sort," said the man in charge, coming to the side of the car. "The track's clear enough, but I guess there'll be a dirt train along most any minute. Are you for runnin' in over the points out of the way?" At that moment Jim caught sight of something coming towards him. Suddenly there appeared over the brow of the incline the rear end of a dirt train, and a glance told him that it was loaded. A man was racing along beside one of the cars, somewhere about the centre of the train, and was endeavouring to brake the wheels with a stout piece of timber. Jim saw the timber suddenly flicked to one side, the man was thrown heavily, then, to his horror, there appeared a whole length of loaded cars racing down towards him, with nothing to stop the mad rush, not even an engine. "Gee, she's broken away from the loco!" shouted the man at the points. "She's runnin' fast now, but in a while she'll be fair racing. Time she gets here, which'll be within the minute, she'll be doing sixty miles an hour. She'll run clear way down to Gatun. Come right in over the points." He ran to open the switch, so that Jim could reach safety, while our hero accelerated his engine in preparation for the movement. Then a sudden thought came to his mind. He recollected the passenger train which was coming on behind him. "Man," he shouted, "there's a passenger coming 'way behind us! The cars were filled with people when I passed. She's ahead of the dirt trains, and of course does not expect to have a full spoil train running down on this line. She'll be smashed into a jelly." "So'll you if you don't come right in," cried the man, waving to Jim frantically. But he had a lad of pluck to deal with. Jim realized that between himself and the oncoming passenger train, now some six miles away perhaps, there lay a margin of safety for himself, if only he could run fast enough before the derelict spoil train racing towards him. But that margin might allow him to warn the driver of the passenger train. He took the risk instantly, shouted to the pointsman, and began to back his car. Fortunately it was one of those in which the reverse gear applied to all speeds, and, since there was no steering to be done, he was able to proceed at a furious pace. "Get to the telephone," he bellowed to the man as he went away. "Warn them down the line."