"The rats send the code through rock seams that carry sounds well," said Luxa. "This is a tap." She hit the stone wall once with her fingernail. "A click." She made two very quick, softer hits. "And a scratch." She scraped her nail briefly on the wall. "A short pause indicates the break between letters and a longer pause, the break between words. I cannot really replicate it at full speed. Can you, Temp?"
"Like this, it sounds, like this," said Temp. He placed his foot on the floor and began to drill out a series of taps, clicks, and scratches that were so rapid that Gregor's ears could never have sorted them out. Especially those taps and clicks. Of course, when his dad had played a Morse code message for them on the computer, even a really slow one, that had seemed unintelligible, too.
"We have many spies positioned at strategic points to record the messages. It is not difficult to intercept, as the rats make no effort to conceal it when it is encoded. Then the messages are written down by humans and flown to the code room," said Luxa.
No one had been bothering to translate the chicken-scratch code into regular alphabet letters — probably all of the code team could read it like that, anyway — so Luxa quickly drew up the Tree of Transmission as a guide. She may not have enjoyed learning this stuff in class, but she didn't even have to go out in the main room to copy the tree. She could remember the whole thing by heart.
"I guess that old mouse must have been a pretty good teacher," said Gregor.
"I suppose so," Luxa said. "The tree is not difficult for me to recall."
"It is constructed so that many of the letters most commonly used are represented with fewer beats. The letters E, A, and I for instance, require only one signal. T and R require only two," said Luxa. "Here, this is easiest to see on the chart." She drew a grid like the one carved into the code room floor.
"It is not perfect in this respect, of course. Because the letter B only requires two signals, although it is much less common than the letter O, which requires three. But the tree was the best balance they could find between speed and ease of remembrance," said Luxa. "Shall we begin?"
Boots seemed to enjoy finding what set of lines matched which alphabet letter a lot more than she had enjoyed their earlier code games.
"Okay, Boots, find straight-straight-straight-left," Gregor said, pointing to the sequence | | |\.
Boots traced along the tree with her chubby finger. "Straight...straight...straight...left...makes X. It makes X, Gre-go!"
"Good job!" said Gregor, and wrote an X above the corresponding lines with one of Lizzie's markers. And so they went on, transcribing the code in low voices, letter after letter, for about an hour. By that time, Gregor had pretty much learned the tree himself. At least learned it well enough to send Luxa this message:
| | / \ | \ / \ \ . | / \ \. /. | | / \. | / | | | / / | / | | | |. | / / | | \. | \ |// \ / \ | / | / / | / \.
She laughed, wadded up the strip of fabric, and tossed it back at him. But as they went on with their task, Gregor wondered if it had been a mistake. She had thought it was funny at first, but now she looked kind of sad. For one thing, it was Henry's joke. So there was all that baggage. For another, any references to dying right now weren't exactly humorous. People had thought the Bane had killed him until he'd walked in. He wished he hadn't sent it but it was too late now.
Boots lost interest in the tree so they made up some other games with the letters on the strips, trying to find words, reading them backward, using their own strategies to try and break the Code of Claw. Luxa and Temp took over the lesson more and more until Gregor was really just observing. Simple, direct thoughts were all his brain could muster. He wanted to go to sleep. He wanted more pain medicine. He wanted to go home. He wanted to go home. He wanted to go home. By the time Ripred called for everybody to take five, Gregor was practically in a trance. He didn't want to join the others for tea and cake, but he was afraid Lizzie would get upset if he didn't, so he dragged himself out of bed.
The code team was too discouraged for chitchat. They ate in silence, occasionally twitching or murmuring something indistinct.
Hazard came in unhappily and sat next to Luxa, leaning his head on her shoulder. "What is wrong?" she asked him.
"They will not let me continue matching the nibbler pups with their parents. They say it is too dangerous. That all of the nibblers must be brought to the palace now," said Hazard.
"They will be safer here," said Luxa.
"Yes, now that the diggers can be heard tunneling toward the arena," said Hazard.
Ripred jerked his head up from his cake. "Can they?" He bounded over to the door. "Am I to get all of my updates from seven-year-old boys?" he bellowed. "Tell Solovet I am not being kept informed!"
"It's not the rats scratching?" Gregor asked.
"Oh, no, Gregor. This sounds completely different," said Hazard.
Ripred turned back to the group, murmuring, "At least they are not digging for the palace. Although why not worries me."
"You think they have another plan to enter it?" asked Luxa.
"I think if they don't, they're working on one," said Ripred. "But as they have never succeeded before, it will have to be quite a plan. In the meantime, they know we'll wear ourselves out bringing in the nibblers."
"Dulcet says I will be needed later," Hazard said. "That I should rest. But I am not sleepy. Can I help in here?"
"Why not?" asked Ripred. "Perhaps some new blood will refresh our minds."
"What are you doing?" asked Hazard. No one seemed to have the energy to answer. Finally Lizzie, who hated it when people ignored her questions, spoke up. "I'll show you." She took the nearest strip of fabric and an aqua-blue marker from her back-pack and sat next to Hazard. "This is a message sent by one rat to another. Those little lines stand for these letters." She quickly wrote the correct alphabet letters above the lines.
"Like the chart on the floor?" asked Hazard.