They rode towards Opole, a region Horn considered reasonably safe. The heir of the land, the young Duke Bolko Wołoszek, was being taken more and more seriously in matters concerning the Opole and Niemodlin regions. Bolko’s antipathy to the bishop and his dislike of the clergy and the Inquisition were widely known. He would not permit any brutality in the Opole region. The bishop and the Inquisitor had threatened the young duke with excommunication, but Wołoszek made light of it.

Horn and Reynevan didn’t have a permanent base but were constantly on the move, operating between Kluczbork, Opole, Strzelce and Gliwice, contacting people coming from Poland: from Olkusz, Chęciny, Trzebinia, Wieluń, Pabianice and even Krakow. There were plenty of issues to deal with and pacts to negotiate. Reynevan, who mainly sat in on the transactions in silence, was amazed by Urban Horn’s commercial ability. He was also amazed by the degree of complication of issues he had previously thought childishly simple.

No two balls, it turned out, were entirely the same. The handgonnes used by the Hussites mainly shot balls with a calibre of one finger. A finger and a grain of barley was the typical calibre of harquebuses, while the barrels of heavier harquebuses had a calibre of two fingers. The barrels of trestle guns were unified to a calibre of two fingers and one grain. Urban Horn had to negotiate the supply of all the kinds of balls in suitable quantities with the owners of Polish forges.

Nor was all gunpowder alike, it became clear, and it was much changed since the times of Berthold Schwarz. The proportions of saltpetre, sulphur and charcoal had to be weighed out scrupulously, depending on what weapon they were intended for—hand weapons needed powder with a higher concentration of saltpetre, and gunpowder containing more sulphur was needed for trestle guns, cannons and bombards. If the mixture was wrong, the powder was unsuitable and only fit for fireworks—poor ones at that. The gunpowder also had to be precisely granulated. If it wasn’t, it separated out during transport: the heavier saltpetre sank downwards to the bottom of the container and the lighter charcoal remained on the surface. Stable and inflammable pellets were created by spraying the ground powder with human urine, and the best results came by using the urine of people who drank much and often. Thus, it was no surprise that powder manufactured in Poland enjoyed a deservedly good reputation on the market and Polish powder mills well-deserved fame.