4 fold out eye test charts pre 1930 and other various optical test materials on card stock by C.H. Stoelting.

The Snellen Test Letters, named after the Dutch ophthalmologist Herman Snellen, are a standardized set of letters used to measure visual acuity, or the clarity of vision. These letters are arranged in rows on a chart, with each row containing letters of progressively smaller sizes. During an eye examination, individuals are asked to read the letters from a specific distance, typically 20 feet or 6 meters. The smallest row of letters that a person can accurately identify indicates their visual acuity. The Snellen chart is widely used by optometrists and ophthalmologists to assess vision and prescribe corrective lenses when necessary.

antique medical, antique psychology, antique science

Some signs of use and discoloration consistent with age.

In house domestic shipping $25.