n.硝石，钾硝，硝酸钾

The recipe for saltpetre is usually kept secret by the manufacturers.
这种火药的配方通常由制造商保密。
The old man used to make saltpetre in his backyard when he was young.
当年轻时，这位老人曾在自家后院制作过火药。
Saltpetre, also known as potassium nitrate, was once widely used in fireworks.
硝石，也就是硝酸钾，曾经广泛用于烟花中。
The miners discovered a large deposit of saltpetre in the mountains.
矿工们在山里发现了一大块硝石矿藏。
The soldiers were trained to use saltpetre as a weapon during wartime.
在战时，士兵们被训练用来使用硝石作为武器。
Saltpetre is crucial in the production of gunpowder and explosives.
硝石对于火药和爆炸物的生产至关重要。
The local government imposed strict regulations on the sale of saltpetre.
地方政府对硝石的销售实施了严格的管制。
The alchemist experimented with saltpetre to create various chemical reactions.
那位炼金术士用硝石进行实验，以创造各种化学反应。
During the industrial revolution, saltpetre played a significant role in the growth of the chemical industry.
在工业革命期间，硝石在化学工业的发展中扮演了重要角色。
Nowadays, saltpetre is primarily used in the preservation of food rather than for military purposes.
现在，硝石主要用于食品的保存，而非军事用途。