An essay on visual glasses, (vulgarly called spectacles) wherein it is shewn ... that the common structure of those glasses is ... very prejudicial to the eyes; the nature of vision in the eye explained, and glasses of a new construction proposed / [Benjamin Martin].

Licence: Public Domain Mark

Credit: An essay on visual glasses, (vulgarly called spectacles) wherein it is shewn ... that the common structure of those glasses is ... very prejudicial to the eyes; the nature of vision in the eye explained, and glasses of a new construction proposed / [Benjamin Martin]. Source: Wellcome Collection.