Mr. Vosburgh, unmolested, climbed to his lofty height of observation. The great city lay beneath him with its myriad lights, but on Third Avenue, from 40th Street northward for a mile, there was a hiatus of darkness. There the mob had begun, and there still dwelt its evil spirit uncurbed. The rioters in that district had cut off the supply of gas, feeling, as did the French revolutionists, that "Light was not in order." Mr. Vosburgh watched that long stretch of gloom with the greatest anxiety. Suddenly from its mystery a rocket flamed into the sky. Three minutes elapsed and another threw far and wide its ominous light. Again there was an interval of three minutes, when a third rocket confirmed the watcher's fears that these were signals. Four minutes passed, and then, from the vicinity of Union Square, what appeared to be a great globe of fire rose to an immense height. A few seconds later there was an answering rocket far off in the eastern districts of Brooklyn. These were indeed portents in the sky, and Mr. Vosburgh was perplexed as to their significance. Were they orders or at least invitations, for a general uprising against all authority? Was the rebellion against the government about to become general in the great centres of population? With the gloomiest of forebodings he watched for two hours longer, but only heard the hoarse murmur of the unquiet city, which occasionally, off to the west, became so loud as to suggest the continuance of the strife of the day. At last he went to the nearest available point and sent his despatches, then stole by a circuitous route to the dwelling of Mr. Erkmann, who was watching for him. Marian's vigilance was sleepless. While she had been burdened throughout the day with the deepest anxieties, she had been engaged in no exhausting efforts, and the novelty of her present position and her new emotions banished the possibility of drowsiness. She felt as if she had lived years during the past two days. The city was full of dangers nameless and horrible, yet she was conscious of an exaltation of spirit and of a happiness such as she had never known. The man whom she had despised as a coward was her protector, and she wondered at her sense of security. She almost longed for an opportunity to prove that her courage could now be equal to his, and her eyes flashed in the darkness as they glanced up and down the dusky street; again they became gentle in her commiseration of the weary man in the room below, and gratefully she thanked God that he had been spared through the awful perils of the day. Suddenly her attention was caught by the distant tramp of many feet. She threw open a blind and listened with a beating heart. Yes, a mob was coming, nearer, nearer; they are at the corner. With a sudden outburst of discordant cries they are turning into this very street. A moment later her hand was upon Merwyn's shoulder. "Wake, wake," she cried; "the mob is coming--is here."