The car, which was some fifty feet long, was very convenient for their purpose. The adversaries might march on each other in the aisle, and fire at their ease. Never was duel more easily arranged. Mr. Fogg and Colonel Proctor, each provided with two six-barreled revolvers, entered the car. The seconds, remaining outside, shut them in. They were to begin firing at the first whistle of the locomotive. After an interval of two minutes, what remained of the two gentlemen would be taken from the car.

Nothing could be more simple. Indeed, it was all so simple that Fix and Passepartout felt their hearts beating as if they would crack. They were listening for the whistle agreed upon, when suddenly savage cries resounded in the air, accompanied by reports which certainly did not issue from the car where the duelists were. The reports continued in front and the whole length of the train. Cries of terror proceeded from the interior of the cars.

Colonel Proctor and Mr. Fogg, revolvers in hand, hastily quitted their prison, and rushed forward where the noise was most clamorous. They then perceived that the train was attacked by a band of Sioux.

This was not the first attempt of these daring Indians, for more than once they had waylaid trains on the road. A hundred of them had, according to their habit, jumped upon the steps without stopping the train, with the ease of a clown mounting a horse at full gallop.

The Sioux were armed with guns, from which came the reports, to which the passengers, who were almost all armed, responded by revolver shots.

The Indians had first mounted the engine, and half stunned the engineer and stoker with blows from their muskets. A Sioux chief, wishing to stop the train, but not knowing how to work the regulator, had opened wide instead of closing the steam-valve, and the locomotive was plunging forward with terrific velocity.

The Sioux had at the same time invaded the cars, skipping like enraged monkeys over the roofs, thrusting open the doors, and fighting hand to hand with the passengers. Penetrating the baggage-car, they pillaged it, throwing the trunks out of the train. The cries and shots were constant. The travelers defended themselves bravely. Some of the cars were barricaded, and sustained a siege, like moving forts, carried along at a speed of a hundred miles an hour.

Aouda behaved courageously from the first. She defended herself like a true heroine with a revolver, which she shot through the broken windows whenever a savage made his appearance. Twenty Sioux had fallen mortally wounded to the ground, and the wheels crushed those who fell upon the rails as if they had been worms. Several passengers, shot or stunned, lay on the seats.

It was necessary to put an end to the struggle, which had lasted for ten minutes, and which would result in the triumph of the Sioux if the train was not stopped. Fort Kearney station, where there was a garrison, was only two miles distant; but, that once passed, the Sioux would be masters of the train between Fort Kearney and the station beyond.

The conductor was fighting beside Mr. Fogg, when he was shot and fell. At the same moment he cried, "Unless the train is stopped in five minutes, we are lost!"