Concave Rowland diffraction grating on speculum metal, grating area 53 x 23 mm, with scratched markings reading 'Plate prepared at the Astronomical / and Physical Instrument Works / of J A Brashear Allegheny, PA USA / 1894' and 'Ruled on Rowlands first [?] Engine / Johns Hopkins University / Baltimore Md USA / 1894', in wooden case marked 'V.210.' A paper label on the box marked in German indicates (according to the donor) that the grating came from Paschen's laboratory.
- Object Number:
case: 25 x 75 x 75 mm
grating block: 10 x 62 x 62 mm
- furnishing and equipment
- tools & equipment
- optical instrument
- optical instrument component
- diffraction grating
- Imperial College of Science,Technology & Medicine (Spectroscopy Group)
- Permanent collection
Cite this page
We encourage the use and reuse of our collection data.
Data in the title, made, maker and details fields are released under Creative Commons Zero
Descriptions and all other text content are licensed under a Creative Commons Attribution 4.0 licence
Download catalogue entry as json
Download manifest IIIF
Our records are constantly being enhanced and improved, but please note that we cannot guarantee the accuracy of any information shown on this website.