Details of exhibit
- Exhibition:
- 1911 Fifty-sixth Annual Exhibition of the Royal Photographic Society of Great Britain
- Exhibit title:
- Iron Arc Spectrum, showing the position of the lines used for the International Secondary Standards of wave-length
- Exhibitor:
- Dr. C. E. Kenneth Mees
- Section:
- V. Scientific Photography and Processes of Reproduction
- Exhibit No.:
- 695
- Description:
- These secondary standards of wave-length were determined separately by Pfund at Baltimore, Eversheim at Bonn, and Fabry and Buisson at Marseilles, the determinations being made by means of the interferometer. The three measurements were usually concordant to two thousandths of a unit, and the means of the three determinations have been adopted. The photograph of the iron arc spectrum which was taken in the second order of an eight foot focus Littrow Spectrograph shows the position of these standard lines.
- Exhibit type:
- Photograph
- Process:
- [Not Listed] ()
- Award:
- none
