Shooting glasses 1880 to 1910
Shooting glasses like this were made in the USA from 1880 to 1910 . The left side lens has a tiny manufacturing lens defect (linear bubble) in it.
They have no refractive correction. Colored lenses were purported to have health value around this era. Amber is known to enhance contrast against a blue sky. (Such as when shooting at birds)
They also come in other color and style combinations.
This type of spectacle is often seen advertised as Civil War “sniper glasses”, etc. However, one can see from their dating that they came along quite awhile after North-South hostilities ceased.