Just below where he sat a little solid sand-bridge spanned the pool. It was full of small holes; and as he looked he perceived that each hole was the entrance to a tube, and the whole bridge was built of these tubes, carefully fitted into one another and glued together.
"Who built this?" he asked.
Instantly a hundred little heads came peeping out of the entrances of the tubes. Each little head was encircled with a delicate ruffle, made not of lace but of exquisite white feathers; and from each little head, as it waved its two little feelers to and fro, came the answer—
"We built the bridge, and we live in it."
Then the Child saw that the pretty sand-bridge was also a city, and was hollowed all through into chambers—each with its beautiful happy little tenant; and he could have watched them all day, the delicate fringed heads peeping out on the clear water-world, each from its own little dwelling built by itself, whilst underneath the arch young shrimps and tiny fishes flashed to and fro.
"Do you build anything besides bridges?" he asked at length.
"Look around you," answered the hundred little busy heads in chorus. And as he looked he saw that the sides of the pool were in many places covered with similar sand-chambers. Here ran out a pier far into the crystal water, dividing it into tiny bays and creeks; there rose a toy citadel, and near it a miniature cliff with peaks; and everywhere, from tiny cliffs, and citadels, and piers, and moles, and bridges, peeped out hundreds of the same delicate little ruffled heads, like courtiers of the olden time.
The Child clapped his hands for pleasure, and longed to see the soldier-crab and make him ashamed of himself.
"But what do you do when the tide is low, and your little cities are left dry?" he asked.
"We each fill up the doorway of our chamber with a drop of water, and retire into the darkness until the next tide," replied the little courtiers.