Sentence:  The profeſſor of the modern <WSD>"Humbugg</WSD>", for ſuch is the polite name of this qualification, muſt either have from nature an unalterable countenance, or from art a power of commanding all its ſucceſſive variations, and preſerving it inviolably in each, as long as the present ſituation of the caſe renders it neceſſary: he muſt have a head full of imagination, and a heart empty of every trace of candor and humanity. 
Meaning of the word marked with <WSD> tags:  A hoax, jest, or prank.