London was the quintessential modern city of the 19th century, and its artists were the first to rise to the challenge of depicting the many facets of this new world. From the 1850s to 1900, the city underwent vast changes, resulting in rapid urbanization, a dramatic increase in population, and the creation of dramatic contrasts between the "gold" of its wealth and splendor and the "mud" of its squalor and poverty. Artists sought to make sense...