Sentence:  The kind of persons who excite or give signal to such revolutions — students, young men of letters […], or fierce and justly bankrupt <WSD>desperadoes</WSD>, acting everywhere on the discontent of the millions and blowing it into flame, — might give rise to reflections as to the character of our epoch. 
Meaning of the word marked with <WSD> tags:  A bold outlaw, especially one from southern portions of the Wild West.