Young Little sat amazed, and drank in his words with delight, and could not realize that this genial philosopher was the person who had launched a band of ruffians at him. Yet, in his secret heart, he could not doubt it: and so he looked and listened with a marvelous mixture of feelings, on which one could easily write pages of analysis, very curious, and equally tedious.
They dined at three; and, at five, they got up, as agreed beforehand, and went to inspect the reservoir in course of construction. A more compendious work of art was never projected: the contractors had taken for their basis a mountain gorge, with a stream flowing through it down toward Hillsborough; all they had to do was to throw an embankment across the lower end of the gorge, and turn it to a mighty basin open to receive the stream, and the drainage from four thousand acres of hill. From this lake a sixty- foot wear was to deal out the water-supply to the mill-owners below, and the surplus to the people of Hillsborough, distant about eight miles on an easy decline.
Now, as the reservoir must be full at starting, and would then be eighty feet deep in the center, and a mile long, and a quarter of a mile broad, on the average, an embankment of uncommon strength was required to restrain so great a mass of water; and this was what the Hillsborough worthies were curious about. They strolled out to the works, and then tea was to come out after them, the weather being warm and soft. Close to the works they found a foreman of engineers smoking his pipe, and interrogated him. He showed them a rising wall, five hundred feet wide at the base, and told them it was to be ninety feet high, narrowing, gradually, to a summit twelve feet broad. As the whole embankment was to be twelve hundred feet long at the top, this gave some idea of the bulk of the materials to be used: those materials were clay, shale, mill-stone, and sandstone of looser texture. The engineer knew Grotait, and brought him a drawing of the mighty cone to be erected. "Why, it will be a mountain!" said Little.
"Not far from that, sir: and yet you'll never see half the work. Why, we had an army of navvies on it last autumn, and laid a foundation sixty feet deep and these first courses are all bonded in to the foundation, and bonded together, as you see. We are down to solid rock, and no water can get to undermine us. The puddle wall is sixteen feet wide at starting, and diminishes to four feet at the top: so no water can creep in through our jacket."
"But what are these apertures?" inquired Grotait.
"Oh, those are the waste-pipes. They pass through the embankment obliquely, to the wear-dam: they can be opened, or shut, by valves, and run off ten thousand cubic feet of water a minute."
"But won't that prove a hole in your armor? Why, these pipes must be in twenty joints, at least."
"Say fifty-five; you'll be nearer the mark."