The Son of Neptune (The Heroes of Olympus #2)(35)

“The cannons on the walls,” Frank said, “they draw water from the aqueduct. There’s a pump system—heck, I don’t know how they work, but they’re under a lot of pressure. If you could control them, like you controlled the river—”

“Frank!” Hazel beamed. “That’s brilliant!”

Percy didn’t look so sure. “I don’t know how I did that at the river. I’m not sure I can control the cannons from this far away.”

“We’ll get you closer.” Frank pointed to the eastern wall of the fort, where the Fifth Cohort wouldn’t be attacking. “That’s where the defense will be weakest. They’ll never take three kids seriously. I think we can sneak up pretty close before they see us.”

“Sneak up how?” Percy asked.

Frank turned to Hazel. “Can you do that thing again?”

She punched him in the chest. “You said you wouldn’t tell anybody!”

Immediately Frank felt terrible. He’d gotten so caught up in the idea...

Hazel muttered under her breath. “Never mind. It’s fine.

Percy, he’s talking about the trenches. The Field of Mars is riddled with tunnels from over the years. Some are collapsed, or buried deep, but a lot of them are still passable. I’m pretty good at finding them and using them. I can even collapse them if I have to.”

“Like you did with the gorgons,” Percy said, “to slow them down.”

Frank nodded approvingly. “I told you Pluto was cool. He’s the god of everything under the earth. Hazel can find caves, tunnels, trapdoors—”

“And it was our secret,” she grumbled.

Frank felt himself blushing. “Yeah, sorry. But if we can get close—”

“And if I can knock out the water cannons…” Percy nodded, like he was warming to the idea. “What do we do then?”

Frank checked his quiver. He always stocked up on special arrows. He’d never gotten to use them before, but maybe tonight was the night. Maybe he could finally do something good enough to get Apollo’s attention.

“The rest is up to me,” he said. “Let’s go.”

XI Frank

FRANK HAD NEVER FELT SO SURE of anything, which made him nervous. Nothing he planned ever went right. He always managed to break, ruin, burn, sit on, or knock over something important. Yet he knew this strategy would work.

Hazel found them a tunnel with no problem. In fact, Frank had a sneaking suspicion she didn’t just find tunnels. It was as though tunnels manufactured themselves to suit her needs. Passages that had been filled in years ago suddenly unfilled, changing direction to lead Hazel where she wanted to go. They crept along by the light of Percy’s glowing sword,

Riptide. Above, they heard the sounds of battle—kids shout ing, Hannibal the elephant bellowing with glee, scorpion bolts exploding, and water cannons firing. The tunnel shook. Dirt rained down on them.

Frank slipped his hand inside his armor. The piece of wood was still safe and secure in his coat pocket, though one good shot from a scorpion might set his lifeline on fire.…

Bad Frank, he chided himself. Fire is the “F-word.” Don’t think about it.

“There’s an opening just ahead,” Hazel announced. “We’ll come up ten feet from the east wall.”

“How can you tell?” Percy asked.

“I don’t know,” she said. “But I’m sure.”

“Could we tunnel straight under the wall?” Frank wondered.

“No,” Hazel said. “The engineers were smart. They built the walls on old foundations that go down to bedrock. And don’t ask how I know. I just do.”

Frank stumbled over something and cursed. Percy brought this sword around for more light. The thing Frank had tripped on was gleaming silver.

He crouched down.

“Don’t touch it!” Hazel said.

Frank’s hand stopped a few inches from the chunk of metal. It looked like a giant Hershey’s Kiss, about the size of his fist.

“It’s massive,” he said. “Silver?”

“Platinum.” Hazel sounded scared out of her wits. “It’ll go away in a second. Please don’t touch it. It’s dangerous.”

Frank didn’t understand how a lump of metal could be dangerous, but he took Hazel seriously. As they watched, the chunk of platinum sank into the ground.

He stared at Hazel. “How did you know?”

In the light of Percy’s sword, Hazel looked as ghostly as a Lar. “I’ll explain later,” she promised.

Another explosion rocked the tunnel, and they forged ahead.

They popped out of a hole just where Hazel had predicted. In front of them, the fort’s east wall loomed. Off to their left, Frank could see the main line of the Fifth Cohort advancing in turtle formation, shields forming a shell over their heads and sides. They were trying to reach the main gates, but the defenders above pelted them with rocks and shot flaming bolts from the scorpions, blasting craters around their feet. A water cannon discharged with a jaw-rattling THRUM, and a jet of liquid carved a trench in the dirt right in front of the cohort.

Percy whistled. “That’s a lot of pressure, all right.”

The Third and Fourth Cohorts weren’t even advancing. They stood back and laughed, watching their “allies” get beat up. The defenders clustered on the wall above the gates, yelling insults at the tortoise formation as it staggered back and forth. War games had deteriorated into “beat up the Fifth.”