Illustrations of optical phenomena: seven figures (numbered 135-141) of spectral distribution and intensity in Frauhofer patterns produced by white light shone through a variety of apertures, including circles. Plate 15 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: 'Oberflõchen der durchschnitte des lichtgebirgs einer kreisrunden Oeffnung.' [Surfaces of the sections of light through a circular aperture]. Inscribed lower right 'lith v. L.Schwerd.'Original: lithograph . 1835
