Annet did not know that her father, having an appointment with the Lord Proprietor at North Inniscaw Farm, designed himself to call at the school on his way back, and row the children home. Had she guessed this it would have prevented the adventure, which, in fact, it furthered; for, coming out of school and hurrying down to the shore to catch Jan and wheedle him, she found the boat moored there empty. Jan, no doubt, had taken a stroll up to the Lord Proprietor's garden, to have a chat with Old Abe. They had caught him napping; and now, if they kept him waiting, he could not grumble. So off the three children set for Piper's Hole; Annet and Linnet with long strides, Matthew Henry trotting to keep up with them. Arrived at the cliff's edge, they deployed with great caution--that no noise might scare the mermaids from coming forth--and searched for a nook where, themselves hidden, they could command a view of the cove at their feet. Linnet, searching to the westward, found just such a spot; a rocky ledge, well grassed, close under the topmost cornice of the cliff, and quite easy of access. To be sure, a rock on their right cut off their view of the cove's inmost recess, where the funnel-shaped slope broke sheer over the mouth of the Hole. But the ledge looked full upon the Mermaid's Rock and the heave of black water surging past it to gurgitate between the narrowing walls of rock. Even the matter-of-fact Linnet could not repress a shiver as, after panting a while, she raised herself on one elbow and looked down into the awesome pit. For not only was the water black, but the whole shadowed base of the cliff wall; black as though stained by the inky wave. Black, too, showed the hither side of the Mermaid's Rock against a gray sea, from which the last tint of sunset had faded. Now and then, between the sobbing of Piper's Hole, the children caught the murmur of the tide race, half-a-mile off shore, slackening its note as it neared the time of high-water and its turning point. Out there the sea was agitated; within the line of the race, sharply defined on the gray, it heaved and sank on an oily swell. "My!" said Matthew Henry, gazing; and Annet turned on her sister and said, "There, now!" The words may seem inadequate, but Linnet understood them, and that they conveyed a question which she felt to be a poser. How could she doubt the existence of mermaids in such a spot as this? If a mermaid were to swim up to the surface under their very eyes, would she be more wonderful than the actual scene--the black rocks, the sobbing water? "Folks," said Annet, incisively, "that laugh at stories about Piper's Hole, ought to come and see the place for themselves." "Yes," Matthew Henry agreed; "and after that they can begin to talk." "I didn't laugh," protested Linnet, flung upon her defence. "Besides," she went on weakly, "I don't see why it must be mermaids. If anything lives down there, why shouldn't it be a dragon---or a giant, perhaps----"