Color blindness : supplemental report on ophthalmology : read before the Medical Society of the State of California, April, 1882 (1882)
Wilder, A. M. (Abraham M.), 1840-1886, author · Sacramento : Day & Joy, printers · leaf 25
age upward, including persons of all grades of society, 217 were found to be color blind; 1,001 of those examined belonged to the superior classes, and showed thirty-one defect¬ ive, or a little over three per cent, while out of 3,491 of the lower classes there were 134, or nearly four per cent.…
Color Vision Defects -- diagnosis · Vision Screening
Internet Archive · U.S. National Library of Medicine · Public domain (published before 1931). Free to use for anything.
