Usage Conditions May Apply Usage Conditions Apply There are restrictions for re-using this media. For more information, visit the Smithsonian's Terms of Use page. IIIF provides researchers rich metadata and image viewing options for comparison of works across cultural heritage collections. More - https://iiif.si.edu View Manifest View in Mirador Viewer Usage Conditions May Apply Usage Conditions Apply There are restrictions for re-using this media. For more information, visit the Smithsonian's Terms of Use page. IIIF provides researchers rich metadata and image viewing options for comparison of works across cultural heritage collections. More - https://iiif.si.edu View Manifest View in Mirador Viewer Usage Conditions May Apply Usage Conditions Apply There are restrictions for re-using this media. For more information, visit the Smithsonian's Terms of Use page. IIIF provides researchers rich metadata and image viewing options for comparison of works across cultural heritage collections. More - https://iiif.si.edu View Manifest View in Mirador Viewer Usage Conditions May Apply Usage Conditions Apply There are restrictions for re-using this media. For more information, visit the Smithsonian's Terms of Use page. IIIF provides researchers rich metadata and image viewing options for comparison of works across cultural heritage collections. More - https://iiif.si.edu View Manifest View in Mirador Viewer Usage Conditions May Apply Usage Conditions Apply There are restrictions for re-using this media. For more information, visit the Smithsonian's Terms of Use page. IIIF provides researchers rich metadata and image viewing options for comparison of works across cultural heritage collections. More - https://iiif.si.edu View Manifest View in Mirador Viewer

This is a filar micrometer, likely made by Brashear of Pittsburgh, and used visually on the 24 inch refractor of the Sproul Observatory, Swarthmore College since its opening in 1913. It contains tiny electrical lamps, and some later modifications. Designed by Klages of Brashear, it connects to telescope by bayonet mount. Filar micrometers were precursors for double star positional astronomy and astrometry prior to the photographic era.

Swarthmore College donated this set of objects to the Museum in 2017.

 Display Status

This object is not on display at the National Air and Space Museum. It is either on loan or in storage.
Object Details
Country of Origin United States of America Type EQUIPMENT-Scientific Devices Manufacturer John Brashear, American
 Dimensions 3-D: 34.3 × 30.5 × 21.6cm, 14.4kg (1 ft. 1 1/2 in. × 1 ft. × 8 1/2 in., 31.7lb.)
 Materials Aluminum Alloy
Copper Alloy (Including Possible Brass)
Ferrous Alloy
Paint
Glass
Plastics
Adhesive
Wood
Adhesive Tape
Electrical Wiring
Rubber
 Inventory Number A20200004000 Credit Line Gift of C. Stuart Hain, Swarthmore College Data Source National Air and Space Museum Restrictions & Rights Usage conditions apply
For more information, visit the Smithsonians Terms of Use.