German Oculus Placido Disk or Keratoscope Opthalmologist Tool antique handicraft forms a hard

forms a hard

It's seen some use

but the tip of one mouthpart on the underside is broken (not visible when worn) and it appears to have lost to the very end tip of the wings

The smaller measures 4 1/2" wide x 2 1/2" tall

There were a few different plate designs produced

German Oculus Placido Disk or Keratoscope Opthalmologist Tool antique handicraft forms a hardI bought this old Placido Disk, or Keratoscope, not knowing exactly what it was, because it reminded me of Duchamp's "Rotoreliefs," and also because I thought it could serve as a great prop for all sorts of things, including perhaps a low budget Sci Fi film! I've since learned that this device, invented in the late 19th century, is an ophthalmic instrument used to assess the shape of the anterior surface of the cornea: a series of concentric rings is