He found that he could cross the burned district a little to the southwest, for the small wooden houses were swept so utterly away that there were no heated, blazing ruins to contend with. He also saw that he could do better by making quite a wide circuit, as he thus avoided streets choked by fugitives. Beaching a point near the river on the west side of the fire, he climbed a high pile of lumber, and then discovered to his horror that the fire had caught in several places on the south side, and that the nearest bridges were burning. To those not familiar with the topography of the city, it should be stated that it is separated by the Chicago River, a slow, narrow stream, into three main divisions, known as the south, the north, and the west side. By a triumph of engineering, the former mouth of this river at the lake is now its source, the main stream being turned back upon itself, and dividing into two branches at a point a little over half a mile from the lake, one flowing to the southwest into the Illinois, and the other from the northwest into the main stream. The south division includes all the territory bounded on the east by the lake, on the north by the main river and on the west by the south branch. The north division includes the area bounded on the east by the lake, on the south by the main river, and on the west by the north branch, while the west division embraces all that part of the city west of the two branches. The fire originated in De Koven Street, the southeastern part of the west side, and it was carried steadily to the north and east by an increasing gale. The south side, with all its magnificent buildings, was soon directly in the line of the fire. When Dennis saw that the flames had crossed the south branch, and were burning furiously beyond, he knew that the best part of the city was threatened with destruction. He hastened to the Washington Street tunnel, where he found a vast throng, carrying all sorts of burdens, rushing either way. He plunged in with the rest, and soon found himself hustled hither and thither by a surging mass of humanity. A little piping voice that seemed under his feet cried: "O mamma! mamma! Where are you? I'm gettin' lost." "Here I am, my child," answered a voice some steps in advance and Dennis saw a lady carrying another child; but the rushing tide would not let her wait--all, in the place where they were wedged, being carried right along. Stooping down, he put the little girl on his shoulder where she could see her mother, and so they pressed on. Suddenly, in the very midst of the tunnel, the gas ceased, by reason of the destruction of the works, and utter darkness filled the place. There was a loud cry of consternation, and then a momentary and dreadful silence, which would have been the preface of a fatal panic, had not Dennis cried out, in a ringing voice, "All keep to the right!"