Refraction and how to refract

Historical Significance: James Munroe Thorington M.D. (1858-1944) was a prolific writer of early text books on refraction, retinoscopy and ophthalmoscopy of which this one. He was adjunct Professor of Diseases of the Eye in the Philadelphia Polyclinic and College for Graduates in Medicine; Assistant Surgeon to Will's Eye Hospital; Ophthalmologist to the Elwyn and Vineland Training School for Feeble-minded Children; Ophthalmologist to the M.E. Orphanage; Lecturer in the Philadelphia Manual Training Schools, 1896-97 on the Anatomy, Physiology and care of the Eyes; Resident Physician and Surgeon Panama railroad Co at Colon ( Aspinwall ), Isthmus of Panama 1882-1889 etc. See his obit JAMA Ophthalmology Dec 1944; 32(6): 511-512. The Museum holds three copies of his early (1900) book on methods of refraction (Cat nos. 59, 1312, 3275, two published in Philadephia and one in London). The Museum also holds his books on retinoscopy (Cat nos 1175 6th edition 1912 , 2249 5th edition1907) and ophthalmoscopy (Cat nos 336 1st edition 1906 as well as his books on refraction of the human eye and methods of refraction (Cat nos 73 1st edition 1916, 335 2nd edition 1930, 814 3rd edition 1939