Inside Out Library · Explore
Standards of form and color-vision required in railway service (1897)
Williams, Charles H. (Charles Herbert), 1850-1918, author, American Ophthalmological Society · leaf 16
17 … FIG. 2. Front view, showing revolving diaphragm with graduated holes, and two London smoke glasses.Color Vision Defects · Mandatory Testing · Railroads
Internet Archive · U.S. National Library of Medicine · Public domain (published before 1931). Free to use for anything.
More pictures from Standards of form and color-vision required in railway service
More like this
