“It seems to be two dragons, two houses for the dragons, and a supply of mutton hung up below,” said Sara, irreverently making game of the royal insignia of Spain. “Oh dear!” she sighed in an under-tone, “I ought to have all this written down.” [Illustration: THE DEMI-LUNE--EXTERIOR.] [Illustration: COAT OF ARMS.] “Here are the main facts, Miss St. John,” said John Hoffman, taking out his notebook. “I collected them several years ago out of piles of authorities; they are authentic skeletons as far as they go, and you can fill them out with as many adjectives, fancies, and exclamation points as you please.” He walked on, joining the others in the inner court-yard, where the Professor, the old sergeant in charge, the piles of cannon-balls, and all the ruined doorways were engaging in a wild mêlée of information. Left alone, Sara and I read as follows: “Fort here as far back as 1565. Enlarged several times, and finally finished much as it now stands in 1755. The Appalachian Indians worked on it sixty years; also Mexican convicts. The inscription over the entrance says that the fort was finished when Ferdinand Sixth was King of Spain, and Hereda Governor of Florida. It has been many times attacked, twice besieged, never taken. Occupied in 1862 by the Fourth New Hampshire regiment.” We had read so far when Aunt Diana came out through the sally-port. “Have you seen Iris?” she asked. “The sergeant is going to show us the window through which the Coochy escaped.” “The Coochy?” “A cat, I believe; some kind of a wild-cat,” said Aunt Diana, vaguely, as her anxious eyes scanned every inch of the moat and outworks in search of the vanished niece. At length she spied a floating blue ribbon. “There they are, back in that--in that illumined thing.” “Oh, Aunt Di! Why, that is the demi-lune.” “Well, whatever it is, do call Iris down directly.” I went after the delinquents, discovering after some search the little stone stairway, nicely masked by an innocent-looking wall, where was a second stone tablet containing the two dragons, their two houses, and the supply of mutton hung up below. There on the topmost grassy stair were the two young people, and had it not been for that floating blue ribbon, there they might have remained in ambush all the morning. “Come down,” I cried, looking up, laughingly, from the foot of the stair--“come down, Iris. Aunt Di wishes you to see the escaped cat.” “I don’t care about cats,” pouted Iris, slowly descending. “I am glad he escaped. Let him go; I do not want to see him.” [Illustration: THE PROFESSOR.] “Iris,” began Aunt Di, “pray what has occupied you all this time?” “The study of fortifications, aunt; you have no idea how interesting it is--that demi-lune.” “Many persons have found it so,” observed John. “We could not quite decide whether it was, after all, a demi-lune or a barbacan,” pursued Iris.