mfortable
chair, smoking an after-dinner pipe. "The logic of the thing appeals to
me. Do you suppose Chahda would know about nulls?"

"What's a null?" Scotty asked.

"In cryptography it's a number, or letter, thrown in for the sake of
appearance, or to confuse."

"Chahda might know," Rick said. "That brown head of his is crammed full
of more odd chunks of information than you could imagine. But if there's
a null in this, which figure is it?"

"Try it both ways," Barby urged. "Here, I'll do it." She counted across
the line. "The third word is 'seventeen.'" She wrote it down. "The ninth
word is 'come.'"

"Could be either," Scotty mused. "But 'come' sounds more likely. Let's
try the next group."

That was 6231581. Rick turned to Page 623 and counted down 15 lines,
including the title. However, he didn't count the page heading. The
heading was on the same line as the page number. Both were above a line
drawn across the top of the page, and it seemed sensible to start below
the line.

"There aren't 81 words on the lines," he said. "So that means another
null, maybe. The first word is 'both' and the eighth word is 'may.'"

Barby wrote them down. "It all makes sense," she pointed out. "It could
be, 'Seventeen may,' or 'come both.'"

"Keep going," Scotty urged. "Try another one."

The third group gave them a choice of "Cheyenne," which seemed unlikely,
or "bad."

"He couldn't be talking about Cheyenne," Rick said. "The word must be
'bad.' That means the first figure of the pair is the null, because it's
the second figure that stands for 'bad.'"

"Sounds reasonable," Scotty agreed. "Keep plugging."

So far, the probable words were: _Come both bad._

Page 276 in the fourth group turned out to be a table of atomic weights.
Line 86 was the element tantalum. If the first figure of the last pair
was assumed to be a null, the word was the symbol for tantalum: "Ta."

Rick stared at it. "Something's wrong. This doesn't make sense."

Barby asked impatiently, "How do we know?"

Rick yielded and moved to the next group. It gave the word "rubles."
"That's Russian money," he said.

The trio looked at it in bewilderment, then Scotty suddenly let out a
yell of laughter. "I've got it! Can't you see? 'Ta' and 'rubles' go
together! 'Tarubles.' Troubles!"

Then they were all howling with joy. Leave it to Chahda to dream up
something like that, Rick thought. So far, the message made sense. _Come
both, bad troubles._

He t