GENERAL INDEX. 



Imperfections of refracting teles<"ies .... 



Impregnation of vegetables, rei i on 



Impression of mother of pearl on wax, &c. producing colours 



of light, direction of, on the eye . . . 



Irnpn, v emejit of telescopes proposed by Mr. Barlow . 

 Impulse distinguished from gravity ..... 

 Inclined plane, its power and experiments on . . 

 Independent parts in the composition of light ... 

 India, method of procuring ice in .... 



Indistinct and distinct vision in the same object . 

 Induration, productive of a doubly refracting structure in bodies 

 Inelastic fluids, observations on . 



Inertia, an universal property of matter . . ... 

 Inflexion, or diffraction of light, observations on 

 Influence of heat in modifying the absorption of light by crystals 



upon doubly refracting crystals . . 



upon Glauberite ..... 



upon calcareous spar . . , . 



upon sulphate of lime 

 Insensibility of the eye to faint light accounted for . . 



of certain eye* to particular colours . . 



OPTICS . . 

 PRELIMINARY TREAT. 

 OPTICS . 



MECHANICS, t. i. 



OPTICS . 



HEAT . 



OPTICS 



POLAR. OF LIGHT 



PNEUMATICS 



Intellectual philosophy defined 

 Intensity of pencils of light, Malus's formulae for 

 Intensities, polarising, of different crystals, table of 

 Interference of the rays of light, laws of 



of polarised light, experiments upon 

 Intermission in the vision of objects seen obliquely 

 Intermitting springs, explanation and cause of 



peculiar one in Devonshire . 

 Involute of a circle, its application in mechanics 

 Iris ornaments, account of . . . , 



Irvine' 's supposed zero of heat in bodies 



OPTICS . 

 POLAR. OF LIGHT 



OPTICS . . 



PRELIMINARY TREAT. 

 POLAR. OF LIGHT 



OPTICS 



POLAR, op LIGHT 



OPTICS 



HYDROSTATICS 



MECHANICS, t. ii. 



OPTICS 



HEAT 



31 



1R 



27 

 38 



. 44 

 28 



. 9 



40-42 



2 



. 54 

 42 

 53 



. 1 

 3 



, 31 



. 48 



62 



63 



. 63 

 63 

 43 



. 49 

 2 

 13 

 30 

 31 

 37 

 43 

 21 

 22 

 89 

 40 

 40 



Java, the swallow of, account of its edible nests . . . PRELIMINARY TREAT. 32 



Juice, gastric, its properties ...... . . 27 



Kaleidoscope, principle of its construction .... OPTICS . . .19 



La Garousse's lever, described ...... MECHANICS, t. ii. . 55 63 



Lantern-wheel, description and application of . . . . 30 



Latent heat, experiments on ...... HEAT . . 41 



in vapours, tables of ..... . . .48 



. . weight of ....... . ... 2 



Latitude, in geography, explanation of the term . . PRELIMINARY TREAT. 17 



Law of descent in falling bodies investigated .... MECHANICS, t. i. . 10 



. of the sines explained ...... POLAR. OF LIGHT . 2 



. of double refraction in crystals ..... . 4 6 



. of the tangents explained . . . . . . 10 



. of the phenomena of coloured rings, by Dr. Brewster . . . 27 



. of double refraction in crystals with two axes . . . 29 



Lawt, general, oflight ..,..,. OPTICS . . 16 



of interference of rays of light .... . . .31 



of spouting fluids ....... HYDRAULICS . 4 



Least resi>tance, the solid of, observations on ... PRELIMINARY TREAT , 22 



Leucocyclit? of Herschel, systems of its coloured rings . . POLAR, or LIGHT . 34 



Lenses denned and severally described ..... OPTICS . . 7 



refraction of light through ..... ... 8 



images formed by ....... . . 12 



magnifying power of . . . . . .14 



spherical aberrations in ...... . . 20 



table of the curvatures of ..... . . .22 



Level, spirit, described ....... HYDROSTATICS . 10 



Lever, principles of, explained ..... PRELIMINARY TRBAT. 18 



as a mechanical power .... MECHANICS, t. ii. . 3 



account of different forms of . . . . . . 6 8 



of La Garousse, described ..... 55 63 



.. perpetual . 22 



,. rectangular described ,, . . 11 



