CHAPTER

21

It was dark when they approached the fort. Every amphorae that did not contain water was filled to the brim with sulfur, as were the sackcloths they had intended to use as tents. Shards of rusted metal were also brought, if only because Cade knew that metal was hard to come by. Perhaps they could use it to forge arrowheads, or to repair Jomsborg’s gates.

Now, he sat alone, listening to the soft snores of the others inside. They had earned their rest, and then some.

Despite the nodding of his head onto his chest, Cade knew he had to stay awake and watch for approaching Grays. If he spotted them before they spotted him, the contenders could slip out of the log cabin and hide in the grass, leaving the enemy to think the place had been abandoned.

A sad consequence of this was they had not set a fire, leaving him bitterly cold as he sat upon an old cannon, staring out over the swaying purple grass.

The moons were clouded that evening, the red and white spheres casting a wan glow over the purple fields. It was difficult to see much at all, and he worried that he had no idea which direction the Grays might come from.

As the minutes ticked by, Cade found himself walking the perimeter; any time sitting down risked falling asleep. Quintus, who had managed to sleep for much of the day in the sled, would take next watch, but it was not for a few hours yet.

It was on one of his circuits of the fort that Cade caught a whiff of the cesspit. Realizing he needed to go, he wandered closer, wrinkling his nose at the stench.

Cade stood at the edge of the giant pit, careful not to get too close as he relieved himself off its edge for fear of falling in. What an ugly end that would be.

And the smell didn’t bother him so much anymore—they all stank of sulfur.

It was an odd thing to do, going to the pit, when he could have easily gone in the grass. But curiosity had taken his feet there. If anything, it broke up the monotony of the night.

The cesspit was more than a hand-dug hole; Cade saw that the Romans had tiled the insides of the pit with clay bricks. This was a useful piece of information—somewhere near here was soil that could be turned into clay. With that, they could make pots, perhaps even mortar and more bricks to repair the broken walls of the fort.

Not that they had time for that. Still, it was an idea.

But there was something odd about the pit’s walls. They shone strangely pale in the moonlight, almost reflected by a white sheen that coated patches of the tiles.

“What is that?” Cade wondered aloud.

There was a flash of blue behind him.

“This substance is potassium nitrate, also known as saltpeter, or salt of the rock.”