aberration of light,315,496Abraham,311,490-1,505-7,509,515-6absolute motion,107orientation,83space,85,93,246,257,353acceleration,94,98,486,509accidental constant,112errors,171,402accommodation of the eyes,67-8action at a distance,137addition,34aim of mathematics,280alchemists,11Alfaro,543algebra,379analogy,220analysis,218-9,279analysis situs,53,239,381analyst,210,221ancestral experience,91Andrade,93,104,228Andrews,153angle sum of triangle,58Anglo-Saxons,3antinomies,449,457,477Arago,540-1Aristotle,205,292,460arithmetic,34,379,441,463associativity,35assumptions,451,453astronomy,81,289,315,512Atwood,446axiom,60,63,65,215Bacon,128Bartholi,503Bassot,542beauty,349,368Becquerel,312Beltrami,56,58Bergson,321Berkeley,4Berthaut,542Bertrand,156,190,211,395Betti,239Biot,540bodies, solid,72Boltzmann,304Bolyai,56,201,203Borel,482Bouguer,537,542Bourgeois,543Boutroux,390,464Bradley,496Briot,298Brownian movement,152,410Bucherer,507Burali-Forti,457-9,477,481-2Caen,387-8Calinon,228canal rays,491-2canals, semicircular,276Cantor,11,448-9,457,459,477Cantorism,381,382,480,484capillarity,298Carlyle,128Carnot's principle,143,151,300,303-5,399Cassini,537cathode rays,487-92cells,217center of gravity,103central forces,297Chaldeans,290chance,395,408change of position,70state,70chemistry of the stars,295circle-squarers,11Clairaut,537-8Clausius,119,123,143color sensation,252Columbus,228commutativity,35-6compensation,72complete induction,40Comte,294Condorcet,411contingence,340continuity,173continuum,43amorphous,238mathematical,46physical,46,240tridimensional,240convention,50,93,106,125,173,208,317,440,451convergence,67-8coordinates,244Copernicus,109,291,354Coulomb,143,516Couturat,450,453,456,460,462-3,467,472-6creation, mathematical,383creed,1Crémieu,168-9,490crisis,303Crookes,195,488,527-8crude fact,326,330Curie,312-3,318current,186curvature,58-9curve,213,346curves without tangents,51cut,52,256cyclones,353d'Alembert,538Darwin,518-9De Cyon,276,427Dedekind,44-5Defforges,542definitions,430,453deformation,73,415Delage,277Delambre,539Delbeuf,414Descartes,127determinism,123,340dictionary,59didymium,333dilatation,76dimensions,53,68,78,241,256,426direction,69Dirichlet,213dispersion,141displacement,73,77,247,256distance,59,292distributivity,36Du Bois-Reymond,50earth, rotation of,326,353eclipse,326electricity,174electrified bodies,117electrodynamic attraction,308induction,188mass,311electrodynamics,184,282electromagnetic theory of light,301electrons,316,492-4,505-8,510,512-4elephant,217,436ellipse,215Emerson,203empiricism,86,271Epimenides,478-9equation of Laplace,283Erdély,203errors, accidental,171,402law of,119systematic,171,402theory of,402,406ether,145,351ethics,205Euclid,62,86,202-3,213Euclidean geometry,65,235-6,337Euclid's postulate,83,91,124,353,443,453,468,470-1experience,90-1experiment,127,317,336,446fact, crude,326,330in the rough,327scientific,326facts,362,371Fahrenheit,238Faraday,150,192Faye,536Fechner,46,52Fehr,383finite,57Fitzgerald,415-6,500-1,505Fizeau,146,149,309,498,504Flammarion,400,406-7flattening of the earth,353force,72,98,444direction of,445-flow,284forces, central,297equivalence of,445magnitude of,445Foucault's pendulum,85,109,353four dimensions,78Fourier,298-9Fourier's problem,317series,286Franklin,513-4Fresnel,132,140,153,174,176,181,351,498Fuchsian,387-8function,213continuous,218,288Galileo,97,331,353-4gaseous pressure,141gases, theory of,400,405,523Gauss,384-5,406Gay-Lussac,157generalize,342geodesy,535geometer,83,210,438geometric space,66geometry,72,81,125,207,380,428,442,467Euclidean,65,93fourth,62non-Euclidean,55projective,201qualitative,238rational,5,467Riemann's,57spheric,59Gibbs,304Goldstein,492Gouy,152,305,410gravitation,512Greeks,93,368Hadamard,459Halsted,3,203,464,467Hamilton,115helium,294Helmholtz,56,115,118,141,190,196Hercules,449Hermite,211,220,222,285Herschel,528Hertz,102,145,194-5,427,488,498,502,504,510Hertzian oscillator,309,317Hilbert,5,11,203,433,450-1,464-8,471,475-7,484Himstedt,195Hipparchus,291homogeneity,74,423homogeneous,67hydrodynamics,284hyperbola,215hypotheses,6,15,127,133hysteresis,151identity of spaces,268of two points,259illusions, optical,202incommensurable numbers,44induction, complete,40,452-3,467-8electromagnetic,188mathematical,40,220principle of,481inertia,93,486,489,507infinite,448infinitesimals,50inquisitor,331integration,139interpolation,131intuition,210,213,215invariant,333Ionians,127ions,152irrational number,44irreversible phenomena,151isotropic,67Japanese mice,277,427Jevons,451John Lackland,128Jules Verne,111,536Jupiter,131,157,231,289Kant,16,64,202-3,450-1,471Kauffman,311,490-1,495,506-7,522,545Kazan,203Kelvin,145,523-4,526-7Kepler,120,133,153,282,291-2Kepler's laws,136,516kinematics,337kinetic energy,116