Why was Mrs. Gardner so drawn to this work when she saw it in Chicago? It is a thoroughly modern painting: the subject is contemporary urban life — people sitting on a Paris trolley — and the style is Impressionist, although the Impressionists never really painted the dreary aspects of public transportation. Zorn depicts the isolation and sadness that comes with industrial progress, even as people are more crowded together.
Source: Richard Lingner, "Omnibus," in Eye of the Beholder, edited by Alan Chong et al. (Boston: ISGM and Beacon Press, 2003): 213