Columbus took Mandy to his cabin.
"You will be safe here," he said.
Curious, Mandy picked up a round metal object.
Its pointy, moving hands were like a clock's.
"What's this?" asked Mandy.
"It's an astrolabe," explained Columbus.
"It measures the height of the sun from the horizon.
It helps us know where we are on the ocean."
Columbus took the astrolabe and said,
"I have to go now. Stay here."
Meanwhile, Vinnie was getting hungry.
A sailor's life wasn't much fun.
"We're all going to starve," said an old sailor nearby.
"Monsters will eat us before we starve!" screamed another.
"I want to go home!" thought Vinnie.
Manuel was tying a knot in a rope.
Another boy was standing by a large coil of rope, holding an hourglass.
When the sand emptied into the bottom, the boy cried:
"One glass is gone.
Now the second begins!"
"What's he doing?" Vinnie asked Manuel.
"We take turns turning over the hourglass.
Each time it empties, a half hour has gone by," explained Manuel.
"After eight turns, or four hours, another boy takes over."
The boy called to Vinnie,
"Hey, take over a minute, will you?"
He put the hourglass into Vinnie's hands.
"It's the second half of the hour," said the boy.
He ran off before Vinnie could protest.
"Here," said Manuel.
He took a biscuit out of his pocket and gave it to Vinnie.
Biscuits were used to mark the time after each turn of the hourglass.
Vinnie thought he was supposed to eat it.
"Ow!" cried Vinnie, after he tried to bite it.
The biscuit was so hard that Vinnie put it down on the ropes.
Meanwhile, Mandy sat alone in the captain's cabin.
The cabin boy had left her a biscuit to eat.
She put it in her pocket.
Suddenly, there was a loud boom.
Mandy, ran out onto the deck.
"What was that?" she shouted.
"It's the Pinta!" cried someone.
"The ship needs help!"
At that moment, she heard a familiar voice shouting,
"One glass is gone, and now the second begins!"
"Vinnie!" she cried happily.
"Mandy! Am I glad to see you!"
he exclaimed when she ran up.
He put the hourglass on top of the ropes.
"What are you doing?" she asked.
"Every thirty minutes, I turn this hourglass over.
Each time, Manuel brings a biscuit.
They're so hard I can't eat them," said Vinnie.
"Don't eat them!"
Mandy shouted, pulling out the photo.
"We need them! See?"
The photo was glowing blue.
"But there are only two biscuits!" cried Vinnie.
"We need three to go home."
"Don't worry," said Mandy, pulling the biscuit from her pocket.
Mandy placed it next to the other biscuits.
In the photo, the hourglass glowed red.
"I'm so glad we're leaving!" cried Vinnie.
The children closed their eyes and fell down the dark tunnel.