GENERAL INDEX, 



Pyrometer, Morveau's and Dr. tire's proposed one . 



HEAt 



37 



a 



Quantity of cohesion in friction determined . MECHANICS, t. iii. 10 



Quartz, curious fracture of a crystal of . . . . OPTICS . . 33 



its refraction ....... POLAR. OF LIGHT . 6 



circular polarisation in . 41 



experiments on, by Fresnel .... . 44 



Quicksilver, account of its freezing . . . . HEAT . . 54, 60 



Rack, double, effect of MECHANICS, t. ii. . 56 



Radiant heat, velocity of . HEAT . .28 



Radiating power of 'heat of different substances in atmospheric 



air, table of . . . . . . . . ... 32 



Radiation of heat, laws of . . . , . . . . . . . 26 



Rainbow, account of, and cause of ..... OPTICS . . 50 



lunar, described ...... . . .52 



secondary ... .... . . 52 



colours of the primary, as seen at the different planets . . .52 



Ram, water, description of that machine .... HYDRAULICS , 20 



Rays of light proceed in straight lines ..... OPTICS . .2 



primary colours of ..... . . 23 



reflected from bodies of the colours of those bodies ... 1 



reflexion of, the general laws of ... . . 16 



interference of . . ... . . . . .31 



refraction of ...... . . 2 



refrangibility of . . .23 



velocity of ...... . . 2 



. . of the sun, their heat when refracted .... HEAT . . 28 



prismatic, comparative temperature of ... OPTICS . . 29 



. . solar, magnetizing power of ..... . . .29 



ordinary and extraordinary, distinguished ... POLAR. OF LIGHT . 2 



Reciprocating springs, cause of . . . . . . HYDROSTATICS . 21 



Reciprocal gravities of bodies . .^ . . . MECHANICS, t. i. . 3 



Rectangular axes, Brewster's theory of . . . . 35 



lever, description of . . ^. . 1. ii. . 11 



Reflected rays of heat, experiments on . . . HEAT . . 29 



Reflecting microscope and telescope, principles of . . . OPTICS . . 20 



and refracting telescopes compared . . . . . 68 



Reflexion, light lost in consequence of . . . . . . . 67 



of rays of light . . 16 



of sounds, laws of ... . . PNEUMATICS . . 30 



Reflexions, successive, produce polarisation . . . POLAR. OF LIGHT . 11 



state of light partially polarised by ... 12 



Refracting (double) crystals, effect of heat upon . . . 62 



telescopes, imperfections of .... OPTICS . . 26 



Refraction of rays of light . . . . . . 8 11 



through prisms .... . . 7 



'. . simple, described . . . . . POLAR. OF LIGHT . 1 



. . double, general account of .... 



. , of Iceland spar ...... 1 



. . axes of, explained ..... . 2 



, . in crystals, laws of . . . . . 4 7 



double, communication of . . ' . . . . 7 



, . connexion between, and polarisation of light . . 29 



double, in crystals, laws of .... 29 



. . new species of, in Analcime .... . 39 



double circular, account of .... 44 



ordinary, polarisation of light by ... 13 



double . 14 



Refractive power of opaque bodies, method of measuring . ^ . 12 



powers of the humours of the eye . . . OPTICS . . 41 



of different bodies, table of ... . . 6 



Refrangibility of the rays of light . . 23 



Regular crystals, effect of pressure on ... . POLAR. OF LIGHT 56 



R*> -liar structure of its hoofs .... PRELIMINARY TREAT. 31 



Malus on the polarisation of light . . POLAR. OF LIGHT 



he least PRELIMINARY TREAT. 22 



servations on ..... MECHANICS, t. iii. 



