Sentence:  The Rebs were , to a Massachusetts corporal , `` fighting madmen or not men at all but whiskey + <WSD>gunpowder</WSD> put into a human frame '' . 
Meaning of the word marked with <WSD> tags:  a mixture of potassium nitrate, charcoal, and sulfur in a 75:15:10 ratio which is used in gunnery, time fuses, and fireworks