Bob had persuaded his uncle to let him stop work in the afternoon at four-thirty in order to have time to do the milking and chores, and he found that by hurrying he could get through before six o'clock. So that night in the early twilight, he paced off the length of the south side of the pond and found it was approximately seven hundred feet from the bridge to the forebay. He remembered that, except on rare occasions, the opening between the abutments of the bridge that carried the lane over the brook had always been sufficient to take care of any water. He now measured this space and found that the abutments were eighteen feet apart and from the under side of the timbers to the bed of the brook it was four feet six inches. He returned to the house and got out his notebook and began making some calculations. He found the area of the space under the bridge to be eighty-one square feet. If they could dig a ditch back a few feet from the south bank of the pond, where the ground rose sharply, and throw the excavated earth on the north side of the cut, they would have a channel with two good banks at the expense of making only one. By pacing off eighteen feet of the bank, he had found that the slope of the ground would average about two feet for that distance. The depth of the water along the bank on the south side had been about two feet. By digging three feet below the level of the bottom of the pond it would mean an average cut of six feet. Taking out a block of earth approximately eighteen feet by six feet, of one hundred and eight square feet, would raise the banks high enough to allow for heavy freshets, and the bottom of the ditch, being three feet below the bottom of the pond, would allow for drainage. He now calculated the amount of earth to be removed and found there would be twenty-eight hundred cubic yards to be dug and piled up to form the new north bank of the cut. He had no idea how much time it would require to do this work, or what it might cost if they hired a man to do it for them. After sitting for a few minutes debating the matter, he became so sleepy that he put his notebook in his pocket and went to bed. "How long will it take you to dig a cubic yard of earth and pile it out on one side of a ditch, Uncle Joe?" asked Bob the next morning at the breakfast table. "I don't know, Bob. Why do you ask?" "I wanted to find out how much it would cost to straighten the brook in our new bottom field," he replied. "Well, I know one thing," said his uncle, "and that is that it will cost more than I can afford to spend; and you know, Bob, we have no time for digging ditches ourselves--in fact, it seems to me it was a great mistake to drain the pond at all--the water at least covered the bad-smelling bottom, and we could shoot an occasional wild duck there."