Concave Rowland diffraction grating on speculum me

Made:
1898 in Baltimore and Allegheny City
maker:
Henry Augustus Rowland

Buy this image as a print 

Buy

License this image for commercial use at Science and Society Picture Library

License

Science Museum Group
© The Board of Trustees of the Science Museum

Concave Rowland diffraction grating on speculum metal, grating area 49 x 34 mm, in wooden case marked 'V209.' Scratched markings on grating illegible. Manuscript note inside the case reads 'Ruled on Prof. Rowlands Engine Johns Hopkins University Baltimore Maryland U.S.A. 1898 Plate prepared at the Astronomical Physical instrument works of Mr J Brashear, Allegheny, Tennessee (sic) U.S.A. 1897 14438 lines to 1 inch 568 lines to 1 mm. Very bright one side. Definition excellent. V209'. This is repeated in German. A paper label on the box marked in German indicates (according to the donor) that the grating came from Paschen's laboratory.

Details

Category:
Optics
Object Number:
2000-1442
Materials:
speculum metal and wood
Measurements:
case: 24 x 75 x 75 mm
grating block: 9 x 61 x 61 mm
type:
diffraction grating - reflection
taxonomy:
  • furnishing and equipment
  • tools & equipment
  • optical instrument
  • optical instrument component
credit:
Imperial College of Science,Technology & Medicine (Spectroscopy Group)