could scarcely believe their ears. A boat of their own, on
their own pond! They had never dreamed of anything half so nice.

"Time to be at work!" said Mr. Davy.

All the forenoon, as I watched them from my window, I saw the
embankment growing slowly, but steadily, while the sloping sides of
the hollow became steeper and steeper. At night a visible step had
been taken towards a fishing-pond.

I cannot tell you about every one of the days during which the Davy
boys worked so industriously. At last, however, the excavation was
completed, the embankment raised to the desired height. The frame for
the gate-way stood firm between its crowding sides. Gates were in
progress at the carpenter's, made of solid plank, a door sliding up
and down over an open space near the bottom. This was easily worked by
means of a handle at the top.

"And now," said Mr. Davy, "to get the water into the pond. Patrick and
Michael must build a dam a little way up the creek and the race-way
from a point just above. We shall need a gate similar to the one at
the outlet."

The boys were glad to give way to Patrick and Michael, when it came to
building dams and race-ways. In the mean time they assisted the mason
who was lining the embankment on either side the gate with stone, to
protect it against the action of the water. The stone-boat, a little,
flat vehicle which slides over the ground without wheels, was brought
out, for piles of stone were to be drawn from a distant part of the
farm.

"But I shall want one of you to carry the hod for me," said the mason.

It was arranged that they should take turns at this; so one would stay
and fill with mortar the queer little box which hod-carriers use, and
bear it on his shoulders to the mason, who was fast laying the curved
wall.

"Why do you have the wall laid in this rounding shape, papa?" asked
George. "Why not have it straight?"

"Because the curve makes it stronger to resist the force of the water.
You notice that the mason chooses stones which are larger at one end
than at the other. He lays them so that the larger ends form the outer
side of the curve--the smaller form the inner or shorter side, as you
see by looking at this wall. The stones, thus wedged against each
other, could not be as easily forced out of place as if they were
square in shape, and laid in a straight line. Imagine the water
pressing upon the inner side of the curve. How readily the wall would
give way, and the water c