Snellen Vision Testing Cards Set for Railway, Marine and School Exams, Early 20th C. name tags I of course like to

I of course like to imagine this set was used by a student at the Bauhaus

Plus a great

this piece feels at once modern and rustic

4 1/4" l x 1 7/16" w x 1 1/16" d

Snellen Vision Testing Cards Set for Railway, Marine and School Exams, Early 20th C. name tags I of course like toFound in their original envelop, with Millar and Wel_ (?) Opticians on, Boston stickeron the face and instruction card still inside, this appears to be a complete, or nearly so, set of early 20th c. Snellen vision testing cards. Nineteen cards total, plus instruction card, with three of the cards showing railway signals to be read at a distance of 20 feet as these were commonly used for testing the vision of train conductors railway workers. Included: