Suddenly, without apparent cause, there rose above the murmurs of the street an ominous sound, like that of a fierce wind soughing through a forest of pines. All eyes were directed down the long street upon a line of cars that had been shunted on the street-track; about these moved a group of men in blue uniforms, the sun flashing on their bayonets and the brass shields of their belts. Oliver, stirred by the sound, climbed to the top of the awning-post for a better view and clung to the cross-piece. Every man who could gain an inch of vantage, roused to an extra effort by the distinct roar, took equal advantage of his fellows. Sailors sprang farther into the rigging or crawled out to the end of the bowsprits; the windows of the warehouses were thrown up, the clerks and employees standing on the sills, balancing themselves by the shutters; even the skylights were burst open, men and boys crawling out edging their way along the ridge-poles of the roofs or holding to the chimneys. Every inch of standing-room was black with spectators. The distant roar died away in fitful gusts as suddenly as it had arisen, and a silence even more terrifying fell upon the throng as a body of police poured out of a side street and marched in a compact body toward the cars. Then came long strings of horses, eight or ten in tandem. These were backed down and hooked to the cars. The flash of bayonets was now cut off as the troops crowded into the cars; the body of police wheeled and took their places ahead of the horses; the tandems straightened out and the leaders lunged forward under the lash. The advance through the town had begun. All this time the mob about Oliver stood with hands clenched, jaws tight shut, great lumps in their throats. Their eyes were the eyes of hungry beasts watching an approaching prey. As the distant rumbling of the cars, drawn by teams of straining horses, sounded the nearer, a bare-headed man, with white hair and mustache and black garments that distinguished him from the mob about him, and whom Oliver instantly recognized as Colonel Clayton, mounted a mass of squared timber lining the track, ran the length of the pile, climbed to the topmost stick, and shouted, in a voice which reverberated throughout the street: "Block the tracks!"