_DICK AND HIS FRIENDS: Dew-Ponds_ “I CALL it stupid to talk about there being water-spirits in a pond,” said Joe. “Well, I don’t know that I agree with you,” said Uncle John. “Of course that isn’t the way we explain things nowadays; but if you had lived in those times, I daresay you would have thought as other people thought.” “But it wasn’t spirits that made the water run out, was it?” Joe asked. “No, I don’t think it was,” said Uncle John. “What I should like to know is--can any of you think what did make the water run out?” “Did the sun dry it up?” asked Dick. “Perhaps there was a spring and it stopped running,” said David. “I don’t fancy you have guessed right, either of you,” said Uncle John. “That pond of theirs was a dew-pond filled by dew--filled from the clouds; and it went dry not because there wasn’t plenty of dew in the air to keep it filled up, but because the pond leaked, and the water ran out faster than it could come in.” “So I suppose when they made the new one with fresh clay, it was watertight and didn’t leak,” said Dick. “But I don’t understand now how the dew could fill it up.” “And I don’t understand why they put the bundles of fern and brushwood underneath,” said David. “It isn’t at all hard to understand, really,” said Uncle John. “You see there is always a great deal of moisture in the air. Sometimes it is high up, and then we call it clouds; and sometimes it is low down, and we call it mist or dew. But there is always plenty of it--a never-ending supply. Of course you know how it comes to be there?” “The sun draws it up.” “Yes, the sun draws it up. The sun is always sucking up water from the earth, from the sea and from rivers and lakes and ponds, and from puddles in the road and from clothes hung out to dry. And the warmer the sun is during the day, the more water it sucks up into the air. But in the night when the air is cool, some of this water comes back again: it forms into drops and settles on the grass or on cabbage leaves, or on a book which you may have left out all night on the garden seat. You know that if you go out early in the morning and walk in the grass, you get your boots sopping wet. So if you could find a place that was hollow so that water could gather in it; and if you could keep it cool like a cabbage-leaf, so that the water would settle in it; and if you could make it watertight below so that the water wouldn’t leak out, you would have a dew-pond.” “Why should it be on the top of a hill?” Dick asked. “I suppose because the higher up you go, the more chance you have of getting into the clouds and the moist air; dew falls more abundantly on the sides of hills.” “But why did those people put the bundles of fern and stuff under the clay?” asked Joe. “That didn’t help to make it water-tight did it?”