Ships continued to be built mostly of timber in the Early Modern Era, thus making them vulnerable to being mined or set ablaze. While some nations invested in crafting better artillery pieces or building more resistance (ie copper plating for ship hulls), there was also a running interest in more exotic weapons and the most esoteric of military fads in the West. The humble Fireship could no longer be just an impromptu reaction — it could now be formed into a sophisticated weapon of mass destruction, with a better understanding of nautical engineering and military science.