"Mysteries!" Donald pricked up his ears. "Oh, I say, I'd like to hear them," and before Robin could exactly make up his mind on the matter, the subject was well under way. "There's—well there's a whole heap of mysteries," said Peter eagerly, "little ones and a big one. Brownie's in some of them, at least she certainly knows something about one, and I've an idea that she knows more than she'll own about your noise, Jan, if you ask me. And then there's my noise, and I——"  
"What on earth!" gasped their bewildered cousin, who felt almost suffocated with mysterious affairs already.
 
"It does seem a bit muddly, I own," Peter grinned, "but we're properly muddled with them all, I can't tell you. First night we slept out Jan saw a light shining from the Chase windows; thought it was mother, and next morning thanked her politely for her beacon, only to hear that Mother had never thought of such a thing. Of course there might easily be an explanation of a light, but——"
 
"But," interrupted Jan, eager to have something to say in the matter, "I've never seen it again, for I've looked. I wondered why; and besides, I believe it shone from one of the windows of the empty wing."
 
"Some servant looking round last thing?" suggested Donald.
 
"We've only two, and that's why the house is all shut up. They sleep at the back on the other side. Nobody goes round at night, but there might easily be an explanation of the light, I quite think—only, it certainly was there. Go on about your noise, Peter."
 
"My noise happened at midnight or thereabout," said Peter, "I heard it hammering and tinging away. Thump! thump! Bang! bang! as I'm always telling everybody. Then it was gone. And Robin doesn't believe a word of it."
 
"I don't say that," remarked his elder brother suddenly.
 
"What?" Peter turned like a dart, "you're coming round, are you? How's that? You were so positive at first. Perhaps it's because Jan heard a noise last night?"
 
"If you want to know the reason"—Robin stared into the fire,—"well, I happened to have heard it myself. Not the night that you did, Peter, but the next. You were asleep, and I lay and listened: it was a thumping and a banging and a tinging, as you say, and——"
 
"Why in all the world didn't you tell us then?" demanded his younger brother.
 
"I wanted to think," said Robin, "and—well I didn't hear it again. But, of course, Jan did, last night."
 
"Was she sleeping out, then?" inquired their cousin, wrinkling his brows in thought. "I imagined that you said it was wet."
 
"No, she never does. It's against orders. And that makes the whole thing queerer. Our noise was heard when we were camping, and didn't sound far off. It seemed to me to come through the ground, but, perhaps, that would be v............