Euler, on the causes of harmony, 34; impression of the mathematical processes on, 196; on the vibrations of strings, 249, 285, 376.
Euler and Hermann"s principle, 149.
Euthyphron, questioned by Socrates, 1.
Evolute, the word, 342.
Evolution, theory of, as applied to ideas, 216 et seq.
Ewald, 298, 304.
Excluded perpetual motion, logical root of the principle of, 182.
Exner, S., 302, 305.
Experience, communication of, 191; our ready, 199; the principle of energy derived from, 179; the wellspring of all knowledge of nature, 181; incongruence between thought and, 206.
Experimental research, function of, 181.
Explanation, nature of, 194, 237, 362.
Eye, cannot a.n.a.lyse colors, 20; researches in the theory of the, 18 et seq.; loss of, as affecting vision, 98.
Eyes, purpose of, 66 et seq.; their structure symmetrical not identical, 96.
Face, human, inverted, 95.
Facts and ideas, necessary to science, 231.
Facts, description of, 108; agreement of, 180; relations of, 180; how represented, 206; reflected in imagination, 220 et seq.; the result of constructions, 253; a continuum of, 256 et seq.; equations for obtaining, 180.
Falling bodies, 204, 215; Galileo on the law of, 143 et seq., 284.
Falling, cats, 303, footnote.
Falstaff, 309.
Familiar intermediate links of thought, 198.
Faraday, 191, 217, 237; his conception of electricity, 114, 271.
Fechner, theory of Corti"s fibres, 19 et seq.
Feeling, cannot be explained by motions of atoms, 208 et seq.
Fetishism, 186, 243, 254; in our physical concepts, 187.
Fibres of Corti, 17 et seq.
Fick, his theory of diffusion, 249.
Figures, symmetry of, 92 et seq.
Figures of liquid equilibrium, 4 et seq.
Fire, use of, 264.
Fishes, 306.
Fixed note, determining of a, 377.
Fizeau, his determination of the velocity of light, 55 et seq.
Flats, reversed into sharps, 101.
Flouren"s experiments, 272, 290.
Flower-girl, the baskets of a, 95.
Fluids, electrical, 112 et seq.
Force, electric, 110, 119, 168; unit of 111; living, 137, 149, 184; generally 253. See the related headings.
Forces, will compared to, 254.
Foreseeing events, 220 et seq.
Formal conceptions, rAle of, 183.
Formal need of a clear view of facts, 183, 246; how far it corresponds to nature, 184.
Formative forces of liquids, 4.
Forms of liquids, 3 et seq.
Forward movement, sensation of, 300.
Forwards, prophesying, 253.
Foucault, 57, 70, 296.
Foucault and Toepler, method of, for detecting optical faults, 313 et seq., 320.
Foundation of scientific thought, primitive acts of knowledge, the, 190.
Fourier, on processes of heat, 249, 278.
Fox, a, 234.
Franklin"s pane, 116.
Frary, 338, footnote.
Fraunhofer, 271.
Freezing-point, lowered by pressure, 162.
Fresnel, 271.
Fritsch, 321.
Frogs, larvA of, not subject to vertigo, 298.
Froude, 333.
Frustra, misuse of the word, 345.
Future, science of the, 213.
Galileo, on the motion of pendulums, 21; his attempted measurement of the velocity of light, 50 et seq.; his exclusion of a perpetual motion, 143; on velocities acquired in free descent, 143-147; on the law of inertia, 146-147; on virtual velocities, 150; on work, 172; his laws of descent, 193; on falling bodies, 225; great results of his study of nature, 214 et seq.; his rude scientific implements, 215; selections from his works for use in instruction, 368; also 105, 182, 187, 237, 272, 274, 283.
Galle, observes the planet Neptune, 29.
Galvanic, electricity, 134; current, 132; dizziness, 291; vertigo, 298.
Galvanoscope, 135.
Galvanotropism, 291.
Garda, Lake, 239.
Gas, the word, 264; ma.s.s of, enclosed in a cylinder, 179.
Gases, tensions of, for scales of temperature, 174.
Gauss, on the foundations of dynamics, 154; his principle, 154; also, 108, 274.
Genius, 279, 280.
Geography, comparison in, 239.
Geometers, in our eyes, 72.
Geotropism, 289.
German schools and gymnasiums, 372, 373, 338, footnote.
Ghosts, photographic, 73.
Gla.s.s, invisible in a mixture of the same refrangibility, 312; powdered, visible in a mixture of the same refrangibility, 312.
Glove, in a mirror, 93.
Goethe, quotations from, 9, 31, 49, 88; on the cause of harmony, 35.
Goltz, 282, 291.
Gossot, 332.
Gothic cathedral, 94.
Gravitation, discovery of, 225 et seq.
Gravity, how to get rid of the effects of, in liquids, 4; also 228.
Gray, Elisha, his telautograph, 26.
Greased plate, drop of water on a, 8.
Great minds, idiosyncrasies of, 247.
Greek language, scientific terms derivedfrom, 342-343; common words derived from, 343, footnote; still necessary for some professions, 346; its literary wealth, 347-348; narrowness and one-sidedness of its literature, 348-349; its excessive study useless, 349-350; its study sharpens the judgment, 357-358; a knowledge of it not necessary to a liberal education, 371.
Greeks, their provinciality and narrow-mindedness, 349; now only objects of historical research, 350.
Griesinger, 184.
Grimaldi, 270.
Grimm, 344, footnote.
Grunting fishes, 306.
Habitudes of thought, 199, 224, 227, 232.
Haeckel, 222, 235.
Hamilton, deduction of the conical refraction of light, 29.
Hankel, 364.
Harmonics, 38, 40.
Harmony, on the causes of, 32 et seq.; laws of the theory of, explained, 30; the investigation of the ancients concerning, 32; generally, 103. See Consonance.
Harris, electrical balance of, 127, footnote.
Hartwich, Judge, 343, 353, footnote.