Mr. Tucker and Mr. Carter laid the gunpowder and the train, and lighted the latter, and came back across the middle of the embankment.

Being quite safe here from the effect of the explosion, Mr. Tucker was desirous to establish by measurement that the water in the reservoir had not risen so high as the crack in the embankment.

With this view he took out a measure, and, at some risk of being swept into eternity, began coolly to measure the crack downward.

At this very time water was trickling over; and that alarmed Carter, and he told Tucker they were trifling with their own lives.

"Oh," said Tucker, "that is only the spray from the waves."

They actually measured the crack, stooping over it with their lanterns.

When they had done that, Carter raised his head, and suddenly clutched Tucker by the arm and pointed upward. The water was pouring over the top, still in a thin sheet, but then that sheet was gradually widening. The water came down to their feet, and some of it disappeared in the crack; and the crack itself looked a little larger than when last inspected. Tucker said, gravely, "I don't like that: but let me examine the valve-house at once." He got down to the valve-house, but before he could ascertain what quantity of water was escaping Carter called to him, "Come out, for God's sake, or you are lost."

He came running out, and saw an opening thirty feet wide and nearly a foot deep, and a powerful stream rushing over it.