"I say," said Daisy suddenly, watching her hair-ribbon flap on the floor of the cage, in a little draught from under the door. "I say, I hope no one will think I've stolen the cat! Mother would know that was a piece of my hair-ribbon if ever she saw it"

"Oh, crumbs! I never thought of that," said Pip.

"It's all right," said Fatty. "I've got a big envelope here — see? Now then, let's each put into the envelope the same thing that we've already settled for dues. I'll put in two cigar-ends, to match the ones I've left. Daisy, put in your other half of ribbon."

Daisy did so. Then Bets put in one of the blue doll's buttons, Larry put in the other shoe-lace, and Pip put in a peppermint drop.

Fatty folded up the envelope carefully and put it into his pocket. "If any of us is accused of the theft, because of the clues we've put in the cage, we've only got to show them what's in this envelope for them to know we did it for a joke," he said.

A bell rang out in Pip's house, and Bets gave a groan. "That's my bed-time bell. Blow! I don't want to go."

"You must," said Pip. "You got into a row yesterday for being late. Oh dear, I do wish we could stay here and see old Clear-Orf and Tupping finding the dues we've left!"

"Well, let's," said Larry.

"Oh, me too!" wailed Bets, afraid of being left out again. Pip give her a push.

"Bets, you must go! There's your bell again."

"Well, it's your bell too — it means you've got to come in and wash and change into your suit for supper-time," said Bets. "You know it does."

Pip did know it. Larry gave a sigh. He knew that he and Daisy ought to go home too. They had farther to go than Pip and Bets.

"We'll have to go too," said Larry. "Fatty, I suppose you couldn't possibly stay and watch, could you? It really would be funny to see. Why don't you stay? Your mother and father don't bother about you much, do they? You seem to go home or go out just whenever you like."

"All right, I'll stay here and watch," said Fatty. "I think I'll climb that tree there. It's easy to climb, and the leaves are nice and thick. I can see everything well from up there, and not be seen myself."

"Well, come on then, Bets," said Pip, not at all wanting to go. Fatty was going to have all the fun.

Then there came the sound of men's voices up the garden, and the children looked at one another at once.

"It's Tupping and Clear-Orf coming back," whispered Larry. "Over the wall, quick!"

"Good-bye, Fatty, see you tomorrow sometime," said Pip in a low voice. The four ran quietly to the wall. Pip gave Bets a leg-up, and got her safely over. The others were soon safely on the other side. Fatty was left by himself. He shinned up the tree very quickly, considering his plumpness.

Fatty sat on a broad bough, and carefully parted the leaves so that he could see what was going on down below. He saw Mr. Tupping coming towards the cat-house with Clear-Orf.

"Well now," Clear-Orf said, "we'll just have a look-round, Mr. Tupping. You never know when there's clues about, you know. Ah, many a clue I've found that's led me straight to the criminal."

"Ah!" said Mr. Tupping wisely, "I believe you, Mr. Goon. Well, I shouldn't be surprised if that boy Luke hasn't left something behind. He may be clever enough to steal a valuable cat, but he wouldn't be clever enough to hide his tracks."

The two men began to hunt carefully round and about the cat-house. The Siamese cats watched them out of brilliant blue eyes. They could not imagine why so many people came to their shed that day. Fatty looked down at the hunters, carefully peering between the leaves.

Mr. Goon found the cigar-end under the cat-house first. He pounced on it swiftly and held it up.

"What's that?" asked Mr. Tupping in astonishment.

"Cigar-end," said Mr. Goon with great satisfaction. Then he looked puzzled and tilted back his helmet to scratch his head. "Does that boy Luke smoke cigars?" he asked.

"Don't be silly," said Mr. Tupping impatiently. " 'Course not. That's not a clue. Somebody who came with Lady Candling to see her cats must have chucked his cigar-end away under the house. That's all."

"Hmmm!" said Mr. Goon, not at all wanting to dismiss the cigar-end like that. "Well, I'll have to think about that."

Fatty giggled to himself. The two men went on searching. Mr. Tupping straightened himself up at last.

"Don't seem nothing else to be found," he said. "I suppose there wouldn't be anything in the cat-house to see, do you think?"

Mr. Goon looked doubtful. "Shouldn't think so," he said. "But we might look. Got the key, Mr. Tupping?"

Mr. Tupping took the key down from a nail at the back of the cat-house. But before he had unlocked the door Mr. Goon gave a loud exclamation. He had looked through the wire-netting of the cat-house and had seen various things on the floor that caused him great excitement. Why, the place seemed alive with clues I

"What's up?" asked Mr. Tupping.

"Coo! Look here! See that shoe-lace there?" said Mr. Goon, pointing. "That's a whopping big due, that is. Somebody's been in there and lost his shoe-lace!"

Mr. Tupping stared at the shoe-lace in the greatest astonishment. Then he saw the blue button — and the hair-ribbon. He gave a gasp of surprise. He inserted the key in the lock and opened the door.

The two men collected the "clues" from the cat-house. They brought them out to look at them.

"Whoever went in there wore shoes with brown laces, that's certain," said Mr. Goon with great satisfaction. "And look at that there button — that's come off somebody's coat, that has."

"What's this?" asked Mr. Tupping, showing Mr. Goon Pip's peppermint drop. Mr. Goon sniffed at it

"Peppermint!" he said. "Now, does that boy Luke suck peppermints?"

"I expect so," said Mr. Tupping. "Most boys eat sweets. But Luke don't wear a hair-ribbon, Mr. Goon. And look, there's another cigar-end — like the one you found under the house."

Mr. Goon soon lost his excitement over his finds, and became puzzled. He gazed at his clues in silence.

"Judging by these here clues, the thief ought by rights to be someone that smokes cigars, wears blue hair-ribbons and blue buttons, sucks peppermint drops, and has brown laces in his shoes," he said. "It don't make sense."

Fatty was trying his hardest not to giggle out aloud. It was so funny seeing Mr. Goon and Mr. Tupping puzzle their heads over all the clues that the children had so carefully left for them to find. Mr. Goon cautiously licked the peppermint drop.

"Yes; it's peppermint right enough," he said. "Well, this is a fair puzzler — finding all these dues, and nobody we can fit them to, so to speak. You finding anything else, Mr. Tupping?"

Mr. Tupping had gone into the cat-house, and was looking all round it again very, very carefully.

"Just looking to see if there's any clue we've overlooked," he said. But he couldn't seem to find anything else, however hard he hunted. He came out again, looking rather untidy and cross.

"Well, there don't seem much else to be found," he said, sounding very disappointed. "I'm sure you'll find it's that boy Luke, Mr. Goon, that's the thief. These clues can't be clues — just things that got into the cage by accident."

"Well, a peppermint drop seems a funny sort of thing to get into the cage by accident," said Mr. Goon grumpily. "I'll have to take all these things home and think about them."

Fatty chuckled deep down in himself as he watched Mr. Goon put his "clues" into a clean white envelope, lick it up, write something on it, and put it carefully into his pocket. He turned to Mr. Tupping.

"Well, so long!" he said. "Thanks for your help. It's that boy Luke, no doubt about it. I've told him I'll go along and give him a thorough questioning tomorrow, and if I don't force a confession out of him, my name's not Theophilus Goon!"

And with that mouthful of a name old Clear-Orf departed majestically down the path, his "clues" safely in his pocket, his mind puzzling them over.

Fatty longed to get down the tree, go home, and have some supper. He suddenly felt tremendously hungry. He peered down to see if Mr. Tupping had gone. But he hadn't

He was in the cat-house again, hunting about very carefully. After a while he came out, looking thoughtful, locked the house, and went off up the path still looking thoughtful. Fatty waited till his footsteps had died away, then slithered down the tree.

"Well, we'll see old Luke tomorrow and ask him no end of questions," thought Fatty as he went home. "My word — this has been an exciting day!"

But there were more exciting things to come!