The place where the children were going was a delightful spot for a picnic. A rapid stream ran through the woods, dashing down over great boulders, making little cascades and waterfalls as it went, with here and there a deep, clear pool, where the trout lay snugly under the stones; the rocks under the overhanging trees were carpeted with the softest and greenest of moss, and tall ferns grew right down to the water's edge, mingling with trailing ivy and creeping moneywort. A grassy glade under a tall beech seemed intended by Nature for a summer-house, for there was a large flat stone in the middle, which served for a table, and a circle of little stones round, just high enough for seats, so that you might imagine Queen Mab and her fairies dined here on moonlight nights, with the squirrels for guests and the bats and owls for waiters.