The man in the very fancy chair is Charles Atwood. This is one of the few photos I've found of the enigmatic Atwood, who served as Daniel Burnham's lead designer and partner from John Root's death in 1891 until his own demise in 1895. (Credit Charles Moore's "Burnham, Planner of Cities.") The man sitting to Atwood's right is the widely respected American classicist,Francis Davis Millett, responsible for color selection and decoration at the 1893 World's Fair.
Francis Davis Millet
(Millet is a story in his own right. After years of a "Bohemian lifestyle," Millet settled down, chosing Mark Twain to be best man at his wedding. He was last seen on the night of April 14, 1912 assisting women and children into the lifeboats of the Titanic).