Antique silver wire eyeglasses with 180 degree lens holder numbered from 0 - 180 degrees. Does anyone know what these were used, date and origin?
Perhaps it had/has to do with rotating specific grinds to find the best one and position for each eye?
Maybe a compass casing repurposed as frames for reading glasses? They look handmade, & not by someone who made a business of it. Antique steam punk? Addendum: I know! They were Benjamin Franklin's. Waste not, want not. Kidding, in case not obvious.
https://www.etsy.com/listing/84228610/oculist-trial-lense-antique-kit Don't know if I did link right. ( these are close)
@AntiqueFinds' look like they've been battered to hell and back, BUT they DO look like an early version of what @Huntingtreasure found!!!!!
That's what I was thinking too. I'd put some lenses in those and wear them as seriously cool steampunk readers.
I could've told you what they were without the link. But yes, that is what they are - supporting frames for trial lenses. As someone who's worn glasses since the age of three, I'm VERY familiar with these things.
They are for measuring astigmatism, the degree marks are to calibrate the degree of abberation for the final spectacle construction. Obviously they can also be used to test degrees of strength of lenses as well. Probably mid to late 19th C and if silver should have some kind of mark depending on the country they were found in.
They do not measure astigmatism as an optometrist/doctor uses a Phoropter for the exam, modern basic check is an autorefractor.The optometrist uses the frame and lenses to fine tune the prescription.
