“Well, sir, I had to think fast. Y’see, we meant to fix ’em all up but we were still a few bars shy.”

Jupe felt sick inside. “Was it that man who was here the other day? The one called Olsen?”

“Not that feller. Another chap. Very likeable sort of man. Truth is, Jupe, even though I had my mind made up to save those cages for a circus, this chap’s work was close enough to help me change my mind.”

“It was?” Jupe repeated dully.

Titus Jones nodded, drew deeply on his pipe, and blew smoke. He finally went on. “Well, on account of him being such a nice chap and worried so, needing ’em so bad, I decided to co-operate. We all worked like the dickens fixing the cages and hunting for bars. Now your aunt saw you drop a bar near your workshop — that was the other day — and she picked that one up.”

“Oh, Aunt Mathilda did?” Jupiter groaned.

His uncle nodded. “A good thing, too. We were still one bar too little even with that, until Hans found another one on your workbench, Jupe. We figured you had no earthly use for it. Bars and junk like that come in here all the time, you know, and you’re always welcome to what you want — providing we don’t need it for a customer. Right?”

Jupe nodded dumbly.

His uncle smacked the dottle from his pipe. “Well, that feller couldn’t believe his eyes when we showed him we had the four cages all ready to go. Paid me a hundred dollars apiece, without my even painting ’em up. Said his animals would feel at home in ’em just like they were.”

“You got those cages over in the Chatwick Valley, didn’t you, Uncle Titus.”

“Yep. At a big scrap yard. They didn’t care about cages. Their main business was in junked cars. Had a terrific machine to eat ’em up. Made a racket, it did.”

Jupe gestured helplessly, his worst suspicions confirmed.

As Mr. Jones stretched and stood up to leave, Jupiter had only one more question. “This man with the animals, Uncle Titus — the one you sold the cages to — did you get his name?”

His uncle smiled benevolently. “Of course I did. Easy one to remember, too.” He squinted into the distance to remember the easy name. “It was, lemme see — yep, Hall. That was his name, all right. Jim Hall.”

Jupiter stared at his friends.

A call to the Rent-’n-Ride Auto Agency found Worthington available soon for another trip to Jungle Land. While waiting for him to arrive, the boys gobbled some lunch in Aunt Mathilda’s kitchen.

“All right, Jupe,” said Bob as the boys settled into the back seat of the Rolls-Royce. “It’s about time you explained what’s going on.”

“It’s very simple,” said Jupe. “The diamonds are being smuggled by the Hall brothers in iron bars.”

“Are you feeling all right, Jupe?” Pete asked. “That iron bar I picked up at the scrap yard and handed you — are you talking about that kind of bar?”

Jupe nodded.

“But that bar was solid iron,” Pete said. “How can you smuggle diamonds in something like that?”

“You can’t,” Jupe said. “But you can smuggle diamonds in a hollow bar. Remember I told you that your iron bar felt different? Well, it was. It was a lot heavier than the one I picked up last night when Bo Jenkins was after us. And it was a lot heavier than the bar I put aside when we were unloading Uncle Titus’s truck. It was so much heavier that suddenly everything clicked.

“I knew that I had hollow cage bars, and that Uncle Titus must have bought his bars and cages at the scrap yard where Jim Hall had tossed George’s cage and probably others, too.”

“But how did you know that the two bars you had contained diamonds?” asked Bob.

“Well, I didn’t know for sure,” said Jupe, “until I heard that Jim Hall had bought the cages from Uncle Titus. He never would have returned for them if the smuggled diamonds weren’t still in them. It’s just my bad luck that I had the bars and then lost them. I still don’t know why he waited so long.”

Pete looked puzzled. “I don’t get it. If he knew the diamonds were in the cages, why did he discard them in the first place?”

“Perhaps the heat was on,” Jupe said. “He couldn’t afford to have them traced to his property. My guess is he dumped them over the fence at the scrap yard as a temporary measure, thinking they’d be safe there and he could pick them apart later. But somehow they got mixed up with a lot of other junk there, and my Uncle Titus bought them from the yard owners, along with all the long bars and railings.”

“That’s possible,” said Bob. “Mr. Hall could have then asked the yard owners who bought the junk and traced it to your uncle’s junkyard. Olsen and Dobbsie must have known about the bars, too. Now that I think of it, Olsen first asked for bars when he came to your uncle’s yard. Remember?”

Jupe nodded.

“I wonder if one of those men was the mystery buyer,” added Bob.

“Mystery buyer?” asked Pete.

“Yes, the customer who bought the pile of bars and railings from Mrs. Jones when we were making our first visit to Jungle Land. Those bars might have had diamonds in them, too.”

“Naw,” said Pete. “Those bars were awfully heavy — don’t forget I was the one who carried them. And they were much longer than all the cage bars we’ve ever seen.”

“I’m inclined to agree with Pete,” said Jupe. “I don’t think it matters who bought those bars. It was probably an innocent customer. And, if it wasn’t — well, Olsen and Jim Hall both showed up at our yard later, so they couldn’t have found the diamonds earlier.”

“Hey, Jupe,” said Pete. “What about that bar you found last night? Where did that come from?”

“That one could have got loose and fallen out of a cage when Jim Hall was dumping it into the scrap yard. I wish I knew how many cages were involved here. We know what to look for now, but we don’t know how much to look for.”

“All those bars look alike,” Bob put in. “How can anybody tell which is which? When the cages arrive, they’re all in place. How would Jim Hall know which bars have the diamonds his brother Cal inserted?”

Jupe smiled mysteriously. “There’s a way of knowing.”

Bob and Pete looked at him sourly. They knew from past experience that Jupiter would never divulge the last remaining secret to a mystery until the last possible moment.

Bob frowned. “We still haven’t solved the mystery we were called in to investigate,” he said. “Who is making Jim Hall’s lion nervous? And if Mr. Hall is tied in with the diamond smuggling, who’s letting his wild animals escape from their cages? He might lose Jungle Land if there’s an accident.”

“We’ll know the answer to that when we put all the loose ends together,” Jupe said. “It’s possible Jim Hall himself let George out when we got there the first time, as a diversion. He might have let the gorilla loose, too, and pretended to go off looking for him. If you recall, he came right back to where the gorilla really was pretty fast.”

“Bringing Doc Dawson and his stun gun and saving our lives!” Pete said. “I won’t hold that against him.”

“What about this morning?” Bob asked. “Jim Hall was on the movie set with George. He couldn’t have slipped away to let the black panther out, could he? And have Doc Dawson cover up for him and say it was his own fault?”

“It’s possible,” Jupe said thoughtfully. “Doc Dawson might have an idea of what Jim Hall is up to. He might be trying to cover up for him and maybe to protect Mike, as well. Doc Dawson always seems to turn up when he’s needed. That suggests to me that he is aware of the situation, and able to anticipate just what is going to happen next.”

Soon the Rolls-Royce was entering Jungle Land.

“Drop us at the foot of the hill leading to the Halls’ house, Worthington,” ordered Jupe. “I think that we should arrive discreetly.”

The boys walked up to the quiet white house on the hill. As they came close, they stopped to listen.