INDEX. 233 



Page. 



Common light, azimuths of vibration in 165 



interferences iu 109 



not polarized by total reflection lo8 



Compensator of Mr. Jamin 199 



Compoimd nature of light announced by Newton 11 1 



Conchisions of Mr. Jainhi on changes of phase by reflection Ul9 



Condensation and rarefaction, waves by 15'-i 



Conditions necessary to produce color in crystalline laminae 204-5 



Conical and cylindrical refraction 228-:-!0 



Crystalline form, modifications of, how related to rotatory power 1^5 



plates in polarized light 132-34, 204-1 5 



at oblique incidences Ili3 



eft'.cts of crossing 134, 212-13 



Ci'ystals, primitive formH 141 



principal sections 116 



of one axis 11"), 210-12 



of two axes 130, 21 3-15, 222-24 



positive and negative 116 



crosses and rings seen in 134-36, 214-15, 222-24 



eflfectii of heat upon 141 



elasticity of ether in 162, 215-17 



indexes of refraction in - 116 



homihedral 142 



plagihedral 135 



Cnr^-ea, lemniscate ] 39, 214 



illustrative of undulation 153, 166 



nodal points of 198 



Cycloid, vibrations in 148 



Cylindric and conical refraction 228-.30 



Dark crosses and brushes seen in crystals cut across the axes 134-40, 214-15, 222-24 



Darkness produced by union of two rays of light 114 



De Dominis, cause of rainbow detected by him Ill 



Delezenne's eye-piece l.'U 



Density of ether in different media 158 



Depolarization of light 206 



experiment on by Dovc' 165 



Designs in selenite, colored in polarized light 133 



Dextrogyration and lijevogyratiou, terms defined 135 



Dimensions of rainbow 1 113-14 



Diffraction, CJrimaldi's original observations 114, 172 



measurement of fringes 174 



Diffraction fringes, produced by opaque bodiea gi^erally 172 



by narrow opaque bodies 175 



by opaque disk 179 



by narrow apertures 177 



b}' minute circular ditto 178-80 



by annular ditto 179 



by gratings 181-83 



measurements of 176 



Diffraction interferences, form of trajectories 174, 176 



Diffraction spectra 182 



Direction of refracted rays in double refraction lCO-1, 225 



Discovery of aberration, stellar 1 23 



of circular polarization 137 



of elliptic do ; 133 



of rotatory do. 135, 141 



of colors in crystalline plates 132 



of conical and cylindric refraction 229 



of polarization by reflection 127 



of law of refraction 109 



of law of polarizing angle 128 



Dislocation of nodes of component undulations 198-99 



of rings of crystals in circularly polarized light 139, 211 



Dispersion, Newton's discovery of Ill 



Cauchy's theory of 155 



Double I'efraction 215 



first mention of 114 



phenomena of 115-17 



light polarized by 118, 215 



direction of refracted rays in 160-61, 225 



resultant of elastic resistance in 218-20 



theory of, by Iluyghens 160-61 



by Fresnil 162, 215 



Dove's experiment on depolarization of light 165 



Early notions of light 108 



Eclipses of Jupiter's satellites, velocity of light ascertained by 121 



Elastic bodies, impact of 158 



Elastic fluid, body vibrating in J 151 



tremors produced in 152 



undulations generated in 151-.53 



molecular movements in 157 



Elasticity, surface of 217-18 



equation f!13 



circular sections in 5?21 



viiriations of, in crystals 162, 215-20 



Elastic resistances, resultant of 218-20 



Elliptic polarization of light 138 



