Signedon split ring: G. Oberhaeuser et E Hartnack / à Paris
Inscribedon sticker on bottom of box: No. [illegible] / $ 20.00
Historical AttributesDr. Ernst's label, now crumbled, reads: "Rec'd March ... '43 / G. Oberhaeuser et E. Hartnack / à Paris / From Dept. of Chemistry. No data. / Dr. Trimble finds it with miscellaneous odd lenses and metal parts. / Price label on the box $20.00. / Cf. with the Schiek camera lucida, copied from this design?"
ProvenanceChemistry Department, Harvard University.