One of the main ingredients used make gunpowders is a chemical called saltpetre.

制作火药的一种主要原料，就是一种化学品叫，硝。

Then again one's breakfast bacon; what intolerable stuff, smelling of saltpetre, has been set before me when I paid the price of the best smoked Wiltshire!

然后又是早餐培根；当我买下最好的烟熏威尔特郡时，摆在我面前的是多么令人无法忍受的东西，散发着硝石的气味！

Empty corners formed dark cavities, dust was covering the counters and filling the drawers, whilst a cellar-like odour of saltpetre rose from the bales of cloth that were no longer moved about.

空荡荡的角落形成了黑暗的空洞，灰尘覆盖了柜台和抽屉，而不再移动的布包散发出地窖般的硝石气味。