Page:Popular Science Monthly Volume 7.djvu/765

Rh at Edinburgh in 1871, that Stokes (at least as early as 1852) had fully apprehended the physical basis of spectrum analysis, and had pointed out how it should be applied to the detection of the constituents of the atmospheres of the suns and stars. Balfour Stewart's experiments and reasoning date from 1858 only, and those of Kirchhoff from 1859."

Prof. Stokes, however, gives due credit to Kirchhoff. Thus, in his Presidential Address to the British Association, in speaking of the applications of the spectroscope, he says: