Painter, printmaker, and illustrator. Remembered particularly for picturesque images of Venice and Japan, he also depicted other locales and in the 1890s executed ornamental and allegorical murals. He was born in Cincinnati, where as a young man he worked as an apprentice in a lithography shop, took drawing classes, studied with Frank Duveneck, and developed an enthusiasm for the work of the recently deceased virtuoso Spaniard Mariano Fortuny. In Philadelphia during 1876–77, he pursued additional instruction at the Pennsylvania Academy of the Fine Arts and, at the Centennial Exhibition, scrutinized paintings by Fortuny and others, while also deepening an early fascination with Japanese art. Subsequently he worked as an illustrator for New York magazines and earned admiration for light-filled watercolors. During the first of several European sojourns, in 1880 he associated in Venice with the Duveneck circle and encountered James Abbott McNeill Whistler. Following Whistler's lead, he began to etch suggestive vignettes and produce the pastels for which he became particularly noted. In 1882 in New York, he and William Merritt Chase founded the Society of Painters in Pastel to promote the medium. In Holland during the summer of 1884 he worked outdoors alongside Chase, a frequent companion. While residing in Venice most of the time between 1885 and 1890, Blum completed the charmingly carefree Venetian Lace Makers (Cincinnati Art Museum, 1887), among his best-known works. Characteristically, Blum here concentrated on appearances, little regarding the somber realities of workers' lives. An animated grouping of attractive, appealingly costumed young women, the painting reveals the mature artist's skill in handling light, color, texture, and composition with decorative flourish. Although he drew figures precisely, in outdoor settings particularly, his painterly treatment of other elements yields an impressionist shimmer. In 1890 Blum went to Japan, where he lived for more than two years. Among the first American artists to experience that country at first hand, he recorded his impressions in oils and pastels, as well as published illustrations. After his return to New York, he devoted much of his energy to large mural commissions. He died of pneumonia in New York a month before his forty-sixth birthday.