Illustrations of optical phenomena: four figures (numbered 131-134) of spectral distribution and intensity in Frauhofer patterns produced by white light shone through gratings. Plate 14 from the monograph 'Die Beugungserscheinungen aus den Fundamentalgesetzen der Undulationstheorie analytisch entwickelt und in Bildern dargestellt' [Diffraction in the fundamental laws of wave theory developed analytically and presented in pictures], by Friedrich Magnus Schwerd (Mannheim, 1835). The plate is captioned in descriptive text: 'Lichtflachen d[urch] ein Stabgitter' [Light surfaces through a bar grating]. Inscribed lower right 'lith v. L.Schwerd.'Original: lithograph . 1835
