Sage Greene and the Mystery of the Nature Center Sundial

Mystery Fiction by Arthur Semicolon Doyle

Middle-school mystery solver, Sage Greene, is babysitting her neighbor Cassie on a warm but cloudy day. They strolled to the Walker Nature Center and Cassie joined a group of kids doing activities. Sage waits near the seven-foot-wide Memorial Sun Dial, near the entrance to the center.

Cassie runs to Sage with a paper in her hand. “What’s that?” Cassie asks. Sage replies, “This is a sundial. It tells the time of day.” Cassie says, “Oh, what time does it say?”

There is no shadow on the sundial. Sage looks up at the clouds. “It only works when the sun is out.” “That’s useless,” says Cassie, “Don’t they know that people have phones?” Before Sage can argue about that, Cassie shows her the paper and says, “This is a map for a scavenger hunt. The X’s show where the treasure is.”

Cassie frowns at the map and turns it around and around. “Which way is up?” Sage points to a letter N and an arrow on the map. “You want to hold the map so that arrow is pointing north.” “Which way is north?” Cassie asks. Sage asks back, “They didn’t give you a compass?”

“No. But, oooh! I have a compass app on my phone!” Cassie pulls out her phone and sees that the battery is at 1%. “Oh, no!” she says and she frantically flips through app icons on the phone looking for the compass app. As soon as she presses the Compass app, the screen goes dark. “Ahhh!” Casssie screams. “Sage, use your phone!”

Sage smiles and points. “North is that way, and I know thanks to this.” She pats the sundial. Cassie looks up at the cloudy sky. “But there’s no sun,” she says, “So it’s as dead as my phone.”

How did Sage know which way was north?

Solution:

Sage points to the metal triangle on the sundial. “The part of the sundial that casts a shadow is called the gnomon and it points north. That’s how I knew. Also, the angle of the gnomon matches the latitude of where it is on Earth.” As if on cue, the sun peeks out from the clouds and the gnomon casts a crisp shadow on the sundial. Sage puts an acorn on the dial at the

shadow. Then Sage and Cassie follow the map for the scavenger hunt, hiking around the grounds of the Walker Nature Center.

Later, as they are leaving, Sage shows Cassie that the shadow on the sundial moved since she put the acorn on it. Based on the dial lines, they figure that one hour has passed. “So it's a timer too?” says Cassie. “Who knew sundials had so many apps!”