Like his fellow American landscape painters Asher B. Durand and John F. Kensett, Inness began his training in an engraver’s shop in New York. He studied the 17th-century landscapes of Claude Lorrain, Mein-dert Hobbema and Jacob van Ruisdael. Multiple visits to Europe brought him in contact with the Barbizon School in France and the pre-Raphaelites in England.

Upon his arrival to the United States, Inness took his first spiritual turn under the advisement of the Reverend Henry Ward Beecher, a patron. As Quick writes in the catalogue, Beecher “advocated a more intimate, emotional relationship toward God, which he indicated could be found through ecstatic experiences in nature.” Inness’s spiritual development continued into the 1860s. Through the largely forgotten American painter William Page, Inness discovered Emanuel Swedenborg, the 18th-century Christian mystic and occult philosopher who also influenced Ralph Waldo Emerson and many other artists and writers of the period. Through Swedenborg and Page, Inness developed a “fresh concept of nature as a place of divine harmony and peace,” writes Quick, “together with a technique that was designed to create paintings full of this same harmony and balance.”

Inness’s vision progressed from strict fidelity to the observable world to mysterious images infused with rich atmosphere, which he built up through glazes of translucent pigment. In his famous early painting of Pennsylvania’s Lackawanna Valley, from 1855, now in the National Gallery of Art, “Inness’s representation of Scranton is accurate, even down to the tree stumps in the middle ground,” writes Quick. For “Autumn Oaks” (c. 1876–77), a well known painting in the Metropolitan Museum of Art, Inness incorporated “a complicated process of painting the colors at nearly full intensity, glazing them back, and then adding intense highlights [so that] the color is both deep and intense, and the modeling is full and atmospheric.” As he reached the end of his career in the 1880s and 1890s, the layers deepened, and Inness produced his most haunting works, for example “Early Autumn, Montclair” (1891), now in the Delaware Art Museum, which Quick calls “one of Inness’s great late paintings.”

Martucci’s patronage allowed Quick to examine, personally, all of these paintings and then some. “It was two week-long trips twice a month for three years,” he recalls. “With just a few exceptions, I saw every painting in the book. That was one of the principles, that I actually examine each work. This was critical to the book’s success.” It also sets this book apart from the 1965 catalogue by LeRoy Ireland, which was based largely on black-and-white photographs of the paintings.