Gropper 's alienation was accentuated when on March 24 , 1911 he lost a favorite aunt in the Triangle Shirtwaist Factory fire , a disaster which resulted from locked doors and non-existent exits in a New York sweatshop . Some 146 workers burned or jumped to their deaths on that day in what was New York 's greatest human catastrophe prior to the terrorist attacks of Sept. 11 , 2001
Triangle Shirtwaist Factory fire
Triangle Shirtwaist Factory fire
William Gropper