“And there hasn’t been much progress in deciphering them since then,” said Caine. “The strings and knots the Incas used to keep track of things are still incomprehensible to us.”

“I keep hoping somebody will find an old Spanish document that records what an Inca informant said when he revealed how to interpret the different kinds and colors and lengths of strands in quipu.”

“We all do,” said Caine. “The Spanish burned thousands of quipu. There are only a few hundred left, but, thanks to you, we at least know what exists.”

Selma looked down at the codex on the table. “Meanwhile, we have this.”

“We do,” Caine said. “Is everyone ready?”

The others all nodded. Caine put on his gloves and carefully opened the first page to reveal a striking painting. Tiny Mayans moved across the page, carrying baskets. They were accompanied by warriors in full-feathered battle regalia, wearing quilted armor, carrying round shields and wooden clubs with obsidian chunks along the edges. They went through plants that seemed to signify jungles. In one place, they passed over what appeared to be mountains, then arrived at a river valley. There were columns of glyphs covering the top third of the page.

“This is amazing,” Caine said. “The page is a kind of stylized map, a set of directions. It says it leads from Copán to the Motagua River Valley, which is in Guatemala. See this glyph? It’s ya’ax chich, the Mayan term for ‘jade.’”

“Are those people with the baskets going to find jade?” asked Remi.

“More likely, to trade for it,” said Caine. “Yes, it’s trade. They’re bringing valuable jungle products—bird feathers, jaguar skins, coca—to trade for jade.”

Selma said, “Jadeite was the most valuable substance in the Americas. The only known sources are Burma, Russia, and the Motagua Valley. This appears to show where that is.”

Caine said, “After the Spanish came, the Mayans stopped going there and never told the Spanish where the jade came from. The Spanish wanted only gold and silver, so the location was forgotten. It was quite a mystery for a long time. Then, in 1952, a hurricane passed over the Motagua Valley, and chunks of jade the size of cars washed out of the hillsides.”

Sam said, “Then, until 1952, what we’re looking at would have been a secret?”

“Absolutely,” said Caine. “To the Mayans, a very important secret.”

“And this is only the first page,” said Remi.

As Caine turned the pages carefully, they stared in amazement. There were paintings of gods and heroes engaged in epic stories of creation and the end of eras. There was a factual account of the warfare between Tikal and Calakmul in which Copán backed Tikal. Caine deciphered and translated only enough of each set of glyphs to determine its subject.