The extent of the visual field, as well as the distribution of photochemical substances upon it, has been a study of very great interest ever since the end of the eighteenth century, when the English chemist, Dalton, made the classical study upon himself. He was unable to distinguish the various shades of red and for a considerable time afterwards this particular deficiency in color discrimination was termed, "Daltonism." During the latter part of the nineteenth century the subject was given practical importance by a number of observers, especially by the researchers of Holmgren the Swedish physiologist who emphasized its bearing upon the cause of accidents by rail and on sea by a confusion of colored signals. As a result of these and other researches, it is now a practice in all civilized countries to require test for color blindness in the case of those who in railways or upon vessels may be responsible for the interpretation of signals.
Proceedings of the Iowa Academy of Science
©1924 Iowa Academy of Science, Inc.
Baldwin, Francis Marsh
"Photochemical Distribution on the Retina as Shown by the Perimeter,"
Proceedings of the Iowa Academy of Science, 31(1), 407-415.
Available at: https://scholarworks.uni.edu/pias/vol31/iss1/142