If you asked a person on the street the meaning of swell, they might mention a puffed up injury or as an expression like “Gee, that’s swell!”
But Reg Rom readers would recognize an alternative definition, referring to a Pink of the Pink.
The meaning “wealthy, elegant person” is first recorded 1786; hence the adj. meaning “fashionably dressed or equipped” (1810), both from the notion of “puffed-up, pompous” behavior. (http://www.etymonline.com/index.php?term=swell&allowed_in_frame=0)
Regency Reader 