Jackson was born on March 30, 1856, in West Goshen Township, Pennsylvania, the eldest of the three sons and one daughter of Emily (Hoopes) Jackson and Halliday Jackson, whose family also included a son by the father's first marriage. Halliday Jackson, a devout Quaker whose English forebears had migrated in 1725 from Ireland, was a writer and lecturer and had served as principal of the Friends' Institute in New York City (1849-1854) before returning to Pennsylvania to teach.
Jackson attended Union College in Schenectady, New York, and received the degree of Civil Engineer in 1874. His decision to turn to medicine was made with a friend and fellow engineering student at Union, Joseph Price, after a summer that included travel and working together on an Iowa farm. Enrolling at the University of Pennsylvania, Jackson received the M. D. degree in 1878.
Jackson began general practice in West Chester, but his career was interrupted by an attack of diphtheria which caused a prolonged paralysis of his leg muscles and the focusing muscles of his eyes. During a lengthy convalescence, he became interested in defects of vision, read widely on the subject, and in 1884 moved to Philadelphia to practice ophthalmology, a field in which his early training in mathematics and engineering was of particular advantage. In 1885 and 1886 he published two important monographs on the use of the retinal shadow test, first described a decade earlier by Ferdinand L. J. Cuignet, to measure refractive errors of the eye; these were followed by a detailed study in 1895, Skiascopy and Its Practical Application to the Study of Refraction. Thereafter, his major scientific contributions were in the field of refraction.
He was largely responsible for popularizing the use of the crossed cylinder for testing the amount and axis of astigmatism. Jackson was appointed professor of ophthalmology at the Philadelphia Polyclinic and School of Graduates of Medicine in 1888 and surgeon to Wills Eye Hospital in 1890. Among his important contributions, in addition to his teaching and writing, was his help in establishing the Ophthalmic Section of the College of Physicians of Philadelphia as a distinct entity (1890), in effect raising ophthalmology to the status of a separate specialty in medicine.
Jackson was also instrumental in securing higher standards of professional training, through the creation of the American Board for Ophthalmic Examinations (1916), which later became the American Board of Ophthalmology and was the forerunner of twenty such groups which today certify medical specialists. Convinced that medical skill depended on a knowledge of new developments, Jackson continually urged the need for broader professional education. To provide access to the foreign literature, he founded (1904) the Ophthalmic Year Book, a survey of articles from journals in all parts of the world. He served as its editor until 1917, and when necessary subsidized its publication. Jackson continued his professional activities in Denver. In 1899 he collaborated in the formation of the Denver (later Colorado) Ophthalmological Society, and in 1905 he was appointed professor of ophthalmology at the medical school of the University of Colorado, a post he held until his retirement in 1921. In 1915 he instituted a series of summer congresses for eye specialists, a plan of postgraduate education that has been widely emulated.
In 1918 he became the first editor of the Third Series of the American Journal of Ophthalmology, a post he retained until 1927. For his work in the movement for the prevention of blindness he was awarded the Leslie Dana Gold Medal in 1925. Jackson died in Denver on October 29, 1942, of a heart block at the age of eighty-six. His ashes were scattered over his own land in Hidden Valley, in Rocky Mountain National Park.
Jackson was largely responsible for popularizing the use of the crossed cylinder for testing the amount and axis of astigmatism. Among his important contributions, in addition to his teaching and writing, was his help in establishing the Ophthalmic Section of the College of Physicians of Philadelphia as a distinct entity (1890), in effect raising ophthalmology to the status of a separate specialty in medicine.
Jackson was a member Society of Friends (1939).
On October 9, 1878, Jackson married Jennie L. Price of West Chester. They had five children. In 1894 Mrs. Jackson developed tuberculosis and the family moved to Denver, Colorado, where she died in 1896. Jackson returned to Philadelphia but after two years moved permanently to Denver. On June 2, 1898, he married Emily Churchman of that city; they had no children.
