Signedstamped on envelope: EDMUND SALVAGE COMPANY / P. O. AUDOBON NEW JERSEY
Inscribedstamped on envelope: STOCK NO. 656 / LIGHT NEUTRAL FILTER / DIAMETER 26 MILLIMETERS
in pencil on envelope: 25.5
ProvenanceSalvaged from the Science Center Prep Room, courtesy of Prof. Owen Gingerich.