The air at Base Camp smelled like woodsmoke and slightly burnt porridge.
Ned sat cross-legged on the ground. He carefully opened his Grandfather’s big, leather notebook. The old pages whispered as he turned them. He stopped at a page with a blurry, smudged drawing. It was a footprint. But it was so big, the ink had smeared right off the edge of the paper.
Underneath the giant footprint was a single question. Ned read it out loud. "How does something this large keep moving?"
What do you think it could be? A walking mountain? A cloud with feet?
Professor Hatch peered over Ned’s shoulder. "An excellent question, my boy! We'll need the Steam-Crawler for this one."
Vera was already in the pilot's seat. She polished a big brass lever. SQUEAK, SQUEAK.
Bram tossed his big bag of tools into the back. CLANG, BONG, CLATTER. He gave a thumbs-up. "Ready for anything!"
The hatch sealed with a heavy thud. CLUNK. The engine coughed, then settled into a low, steady rumble. RRRUMMMBLE.
Ned looked out the window. "We’re heading for the Jigsaw Earth. The ground there is all cracked, like a puzzle."
Vera nodded. "And the air gets thin. Can you feel it?" Take a breath. It feels a little shorter, a little lighter. That's thin air.
Ned looked back at the giant footprint in the notebook. He looked at the wobbly, cracked ground outside. An idea began to bubble in his brain.
"I have a hypothesis! An idea we can test!" Ned said. He pointed to the drawing. "Maybe it uses its tail to help it walk. Like a giant balancing pole!"
The Steam-Crawler rolled forward. It left the green of the Tangle behind. The world outside turned dusty brown. The air smelled like warm stones.
The ground was broken into huge, flat pieces. Just like a jigsaw puzzle. As the Crawler rolled over them, the pieces wiggled. WOBBLE, SHAKE.
Suddenly, the whole vehicle gave a big lurch.
CLANG!
A wrench bounced off of Bram’s metal safety boot. "Ow!" he yelped. Then he giggled. "Whoops! Wrench, meet toe."
Vera looked ahead. The cracks in the ground were getting wider. "Hold on, crew! We need some rhythm to get across!"
She started the chant. A steady beat. Feel it in your feet! Chuffa-chuffa-CLACK!
The crew joined in. Chuffa-chuffa-STACK! Pistons PUSH! Boilers ROAR! Expedition RIDGE! Let's explore!
The Steam-Crawler bounced and swayed, but it kept moving right across the wobbly puzzle pieces. Finally, it stopped with a long, gentle hiss of steam. SHHHHHHHHH.
They had arrived. The air was hot and dry, and smelled like baked earth. A shimmering heat wiggled above the dusty ground.
A low GRRRUMBLE echoed from deep in the earth. Vera pointed. "We have to be quick. The path back is already shrinking."
Then, the clouds above them parted. A huge beam of sunlight shone down. It was the Sun-Bridge.
The world went quiet. Listen. Not a peep. Not a rustle.
Then, a shadow fell over the Steam-Crawler. A big, cool shadow. A shadow so large it covered the whole vehicle.
FWUMP.
The sound was deep and low. The ground shook, just a little. A foot as wide as a bathtub had landed right beside them.
Slowly, slowly, they looked up. And up. And up some more.
A long, long neck reached into the sky. A long, long tail stretched out behind, disappearing into the dust. It was a dinosaur. The biggest one they had ever seen.
The dinosaur took another step. FWUMP. It walked toward a huge crack in the ground. A crack too wide to step over.
The giant creature stopped. It stood perfectly still. How would it get across?
Then, its enormous tail began to move. It swayed slowly to the left. SWOOOOOSH. The dinosaur lifted its right front foot. It held it in the air for a moment. Then it placed it gently on the other side of the crack. FWUMP.
Next, the giant tail swayed all the way to the right. SWOOOOOSH. The dinosaur lifted its left front foot. And placed it safely next to the other.
Professor Hatch gasped. "Scientific Fact! Absolutely extraordinary! That is an Argentinosaurus!" He pointed with a shaky finger. "Its tail is like the long pole a tightrope walker uses to keep their balance!"
The Argentinosaurus took two more balanced, swaying steps. And then it was gone, vanishing into the shimmering heat. FWUMP. Fwump.
A louder GRRRUMBLE shook the crawler. Vera’s eyes were wide. "The cracks! They’re getting wider! Time to go!" The engine rumbled back to life.
Let's do the chant! One more time! Chuffa-chuffa-CLACK! Chuffa-chuffa-STACK! Pistons PUSH! Boilers ROAR! Expedition RIDGE! Let's explore!
Back at Base Camp, the warm smell of the campfire wrapped around them like a blanket. A friendly fire crackled and popped. The stars were popping out in the dark purple sky.
Bram opened the big Census Log. He took out a heavy rubber stamp. He pressed it onto the ink pad. SQUISH. Then, he aimed carefully. And stamped the page with a loud, satisfying sound.
KA-CHUNK!
"Discovery Number Seven," Bram announced. "Logged!"
Ned sat by the fire, poking the embers with a stick. He drew a giant footprint in the dirt. Then, he added a long, swooshing line behind it. A balancing tail.
