The Nature of Light: With a General Account of Physical Optics

absorption æther amount angle of incidence angle of refraction aperture appears beam blue body bright lines carbon points centre circle consequently convex convex lens corresponding crown glass crystal dark lines difference of path diffraction direction double refraction elementary waves equal example exhibit fasciculus flame flint glass fluid fluorescence focal distance grating spectrum green half wave-length Heliostat homogeneous Iceland spar illuminated incident rays index of refraction lens lenses luminous point marginal rays medium metal movement Nicol's prism object observed obtained optic axis parallel particles pass perpendicular phenomena placed plane of vibration polariscope polarised ray position principal plane prism propagation Quartz ray of light real image reflected reflexion refracted ray refracting angle refrangible regarded right angles rings rotated screen seen slit Sodium solar spectrum source of light spectra surface telescope thickness tion traverse tube undergoes undulatory vapour velocity vertical violet whilst white light yellow