The throne room’s hysterical crowd erupted with shouts and cries. The Court Scientist released the lever and looked at the king.

Lenora tried to continue speaking but couldn’t hear herself or anything else over the crowd’s bedlam. She whirled to face them. “Everyone—please SHUSH!”

Instantly, the crowd went dead silent and looked wide-eyed at Lenora. She felt a little guilty, but really, a librarian had a right to a bit of silence when needed.

She turned to the king. “It isn’t February 29, Your Majesty,” she said. “It’s March 1!”

The Court Mathematician smirked. “Wrong, librarian. The math proves it.”

Muffled gasps from the crowd.

“No, the history proves it!” exclaimed the Court Historian.

More gasps, and Lenora looked around to see everyone on the tips of their toes, leaning forward, awaiting her response. Her mind raced with the facts she had read in the calendar book. “Neither one proves it alone,” she said carefully. “You have to take both together. Leap years don’t always come every four years. According to the rules, century years, like 1800 and 1900, are not leap years. But they—”

“This is a century year,” interrupted the Court Historian. “It’s 8000. Make up your mind!”

“As I was about to say,” Lenora said, determined to be patient and professional, “that rule switches every four hundred years. 1600 and 2000, for example, were both leap years.”

“Fine!” said the Court Mathematician rudely. “The math still says 8000 is one of those years.”

“Not quite,” said Lenora, pointing a finger to the sky as she reached her dramatic conclusion. “There is something the scientists who built the screen must not have known. By the year 4000 the calendar would have been off by a day, unless they added a rule that switches things every 4000 years. And that means 8000, like 4000 and 12000, must be a common year.”

“I assume,” mused the king, “that a common year is anything that is not a leap year.”

“Correct,” said Lenora.

“Clearly, this librarian knows her calendars.” The king looked at his mathematician and historian, who appeared rather ashamed of themselves and were staring studiously at their toes. “If there are no objections, we shall reset the date to March 1.”

Relief flooded Lenora. But at the same time, she felt that something was still wrong. They had yet to solve the real problem. She could see herself returning here in 12000 and then 16000 and on and on to solve the exact same problem every time. “Pardon me, Your Majesty,” she said, “but I don’t think you should reset the screen. I think you should take it down.”

“Whyever would we do that?” asked the king in surprise.

“Because,” said Lenora, “you don’t want to depend on the screen, do you? It will just mean more confusion every four thousand years.”

“Very wise,” said the king. He turned to the Court Scientist. “Bring down the screen,” he ordered. “From this day forward, we will learn to tell dates ourselves!”