The problem, astonishingly, turned out not to be sulphur or saltpetre, which could fairly easily be bought from the local apothecaries; not resin, which the local tar makers who had sought protection in the town had in abundance; nor powdered antimony, which was sold to them by an alchemist fleeing from Bystřice, at an admittedly quite extortionate price. The ingredient you’d have thought would be the least complicated caused the most problems: oil. There was no oil in Kłodzko. It had all been bought.

There were very few specialised oil merchants in Kłodzko since demand for oil was met entirely by the town presses. The manufacture of oil intra muros occurred in mills and was carried out by millers’ apprentices as a sideline. Now, facing the threat of a siege, some of the apprentices had gone to fight, while those that remained were milling flour for bread day and night.

The invaluable altarist from Our Lady had a solution to that, too. In the parish church, he’d heard the whispered news that one of the local oilmakers had some reserves but was hiding them in order to make a killing at the right moment. Perhaps he might agree to sell a barrel or two. Having declared his readiness to intercede in the negotiations, the altarist went home, for dusk was falling.

The next day, there was a hubbub and excitement in the town. People were hurrying to the Green Gate, so the company also went there. The crowds squeezed onto the walls were pointing at columns of smoke rising to the south. Rengersdorf, Martinov, Hannsdorf and Železno were all burning, the news had it. The black smoke, dispersed by the wind into a ragged plume, soon rose to the west of the town over Schwedeldorf and Roszyce. The townspeople’s anxiety rose to fever pitch. Combined with the earlier tidings about the burning down of Kunzendorf, the smoke to the west could mean only one thing: the Hussites were approaching Kłodzko from two sides.

“Tomorrow,” said Bisclavret, looking meaningfully at Reynevan after they returned. “Královec will reach the town tomorrow.”

“I’ll manage.” Reynevan pointed to five jugs wrapped up in straw. “All we do is add the oil, mix it, bung it and cover it in pitch and it’ll be ready. Then all that’s left is to plant them in the right places. Have you decided where?”

Bisclavret smiled wolfishly. “Indeed,” he drawled malevolently. “It’s all planned.”

“Trutwein should be here any moment now. With good news, God willing.”

Johann Trutwein only showed up at the tenth hour of the day, an hour after the Nones were rung at the Augustinian monastery. But he did indeed have good news. The oilmaker, he announced, would sell the oil. But he was asking…

Bisclavret scowled furiously when Trutwein whispered in his ear. He took the altarist to one side and the two of them argued at length.