Henry Chapman Jones was a chemist and author. Born in London in 1854, Henry Chapman Jones completed his formal education at the Royal School of Mines. After working briefly for the University of London's Birkbeck College, he became a chemistry instructor at the Royal College of Science, which is where he remained in various capacities until his retirement. Mr. Chapman Jones's scientific domain was the campus's "North Laboratory", and after serving on Sir Edward Frankland's staff, he assisted chemistry professors Thomas Edward Thorpe, William Augustus Tilden, and H. B. Baker. In 1879, he received a fellowship with the Royal College of Chemistry. Mr. Chapman Jones's fascination with chemical processes naturally led him to the study of photography. His exhaustive research on technical innovation led to frequent lectures and editorials published by the Royal Photographic Society. An admirer of chemist and photographer Sir William de Wiveleslie Abney, Mr. Chapman Jones applied his scientific photographic principles to his experiments with negative densities, plate sensitivity, and image colorisation. In 1890, when assessing lenses, he determined that manufacturers should strive for "equal defining power," which would improve image definition, and "equal illumination over a flat field," which he acknowledged would be impossible to achieve adequately unless the light at the plate's center could be reduced to match the margin illumination. He authored several important books, including Science and Practice of Photography (1895), considered one of the premier instructional textbooks of its time, and Photography of To-Day (1913). Chapman Jones served as president of the Royal Photographic Society from 1912 to 1914. Henry Chapman Jones died on March 7, 1932, survived by his wife and two sons.