The sextant had long since been discarded, and both men were staring at a rickety tripod, from which a button was suspended by a piece of ravelled thread. The shadow it cast was a dark dot. Madsen spoke first.
"You're quite a gadgeteer, aren't you. It's simple, at that. The closer we are to the equator, the higher the sun, and the shorter the shadow. Voila!"
Morley laughed and stretched. The change in equilibrium set the little pendulum to swinging gently, and he watched it intently as the motion slowly ceased.
"It's been that way for hours now. We should be nearly there."
Madsen scanned the bank. "Any time now, any time."
An hour later they saw it. A quarter mile lane burned through the trees and shrubs, running straight as a string from the horizon to the river, and continuing on the other side. They beached the raft, in case the necessity arose to cross back, and trudged until they came to the first mile marker. They were on the right side. The arrow pointed in the direction they were going, and the enamelled sign said, simply,
JAPETUS D.D. No. 1
12 m.
19 km.
After a pause, Madsen spoke. "We made it, thanks to what you knew about Japetus. All those little things that added up."
"Oh those," said Morley. "Just," he hesitated. "Just—odds and ends."