When the great wave from Conemaugh lake, behind the dam, came down the Conemaugh Valley, the first obstacle it struck was the great viaduct over the South Fork. This viaduct was a State work, built to carry the old Portage road across the Fork. The Pennsylvania Railroad parallels the Portage road for a long distance, and runs over the Fork. Besides sweeping the viaduct down, the bore, or smaller bores on its wings, washed out the Portage road for miles. One of the small bores went down the bed of a brook which comes into the Conemaugh at the village of South Fork, which is some distance above the viaduct. The big bore backed the river above the village. The small bore was thus checked in its course and flowed into the village. [Illustration: GENERAL VIEW OF THE RUINS, LOOKING UP STONY CREEK.] The obstruction below being removed, the backed-up water swept the village of South Fork away. The flood came down. It moved steadily, but with a velocity never yet attained by an engine moved by power controllable by man. It accommodated itself to the character of the breaks in the hill. It filled every one, whether narrow or broad. Its thrust was sideways and downward as well as forward. By side thrusts it scoured every cave and bend in the line of the mountains, lessening its direct force to exert power laterally, but at the same time moving its centre straight on Johnstown. It is well to state that the Conemaugh river is tortuous, like most streams of its kind. Wherever the mountains retreat, flats make out from them to the channel of the stream. It was on such flats that South Fork and Mineral Point villages and the boroughs of Conemaugh, Franklin, Woodvale, East Conemaugh and Johnstown were built. After emerging from the South Fork, with the ruins of the great viaduct in its maw, it swept down a narrow valley until just above the village of Mineral Point. There it widened, and, thrusting its right wing into the hollow where the village nestled, it swept away every house on the flat. These were soon welded into a compact mass, with trees and logs and general drift stuff. This mass followed the bore. What the bore could not budge, its follower took up and carried. The first great feat at carrying and lifting was done at East Conemaugh. It tore up every building in the yard of the Pennsylvania Railroad. It took locomotives and carried them down and dug holes for their burials. It has been said that the flood had a downward thrust. There was proof of this on the banks of the river, where there was a sort of breakwater of concreted cinders, slag, and other things, making a combination harder than stone. Unable to get a grip directly on these banks, the flood jumped over them, threw the whole weight of the mass of logs and broken buildings down on the sand behind them, scooped this sand out, and then, by backward blows, knocked the concrete to pieces. In this it displayed almost the uttermost skill of human malice.