One afternoon they found No. 11 on the side-track, puffing away as if enjoying a quiet smoke before starting.  No cars were attached, and no driver was to be seen, for Bill was off with the other men behind the station-house, helping the expressman, whose horse had backed down a bank and upset the wagon.

“Good chance for a look at the old lady,” said Frank, speaking of the engine as Bill did, and jumping aboard with great satisfaction, followed by Gus.

“I’d give ten dollars if I could run her up to the bend and back,” he added, fondly touching the bright brass knobs and glancing at the fire with a critical eye.

“You couldn’t do it alone,” answered Gus, sitting down on the grimy little perch, willing to indulge his mate’s amiable weakness.

“Give me leave to try?  Steam is up, and I could do it as easy as not;” and Frank put his hand on the throttle-valve, as if daring Gus to give the word.

“Fire up and make her hum!” laughed Gus, quoting Bill’s frequent order to his mate, but with no idea of being obeyed.

“All right; I’ll just roll her up to the switch and back again.  I’ve often done it with Bill;” and Frank cautiously opened the throttle-valve, threw back the lever, and the great thing moved with a throb and a puff.

“Steady, old fellow, or you’ll come to grief.  Here, don’t open that!” shouted Gus, for just at that moment Joe appeared at the switch, looking ready for mischief.

“Wish he would; no train for twenty minutes, and we could run up to the bend as well as not,” said Frank, getting excited with the sense of power, as the monster obeyed his hand so entirely that it was impossible to resist prolonging the delight.

“By George, he has!  Stop her!  Back her!  Hold on, Frank!” cried Gus, as Joe, only catching the words “Open that!” obeyed, without the least idea that they would dare to leave the siding.

But they did, for Frank rather lost his head for a minute, and out upon the main track rolled No. 11 as quietly as a well-trained horse taking a familiar road.

“Now you’ve done it!  I’ll give you a good thrashing when I get back!” roared Gus, shaking his fist at Joe, who stood staring, half-pleased, half-scared, at what he had done.

“Are you really going to try it?” asked Gus, as they glided on with increasing speed, and he, too, felt the charm of such a novel adventure, though the consequences bid fair to be serious.

“Yes, I am,” answered Frank, with the grim look he always wore when his strong will got the upper hand.  “Bill will give it to us, any way, so we may as well have our fun out.  If you are afraid, I’ll slow down and you can jump off,” and his brown eyes sparkled with the double delight of getting his heart’s desire and astonishing his friend at the same time by his skill and coolness.

“Go ahead.  I’ll jump when you do;” and Gus calmly sat down again, bound in honor to stand by his mate till the smash came, though rather dismayed at the audacity of the prank.