IX. Wave-length determinations and general results obtained from a detailed examination of spectra photographed at the solar eclipse of January 22, 1898

Abstract

The results are here given of a detailed study and measurement of a series or ten spectra, photographed by me with a small prismatic camera, at the eclipse camp of the British Astronomical Association stationed at Talni, India. The instrument referred to had an aperture of 50 millims., and a focal length of about 890 millims. It wTas fitted with two crown-glass prisms, each of 60° angle, placed in front of an ordinary visual objective, the component lenses of which were slightly separated in order to shorten the focus of the ultra-violet rays relatively to those of the visible spectrum.