theory of gases,141Kirchhoff,98-9,103-5Klein,60,211,287knowledge,201König,144,477Kovalevski,212,286Kronecker,44Lacombe,543La Condamine,535,537-8,542-3Lagrange,98,151,179Laisant,383Lallamand,543Langevin,509Laplace,298,398,514-5,518,522,538Laplace's equation,283,287Larmor,145,150Lavoisier's principle,301,310,312law,207,291,395Leibnitz,32,450,471Le Roy,28,321-6,332,335,337,347-8,354,468Lesage,517-21Liard,440Lie,62-3,212light sensations,252theory of,351velocity of,232,312Lindemann,508line,203,243linkages,144Lippmann,196Lobachevski,29,56,60,62,83,86,203Lobachevski's space,239local time,306-7,499logic,214,435,448,460-2,464logistic,457,472-4logisticians,472Lorentz,147,149,196-7,306,308,311,315,415-6,492,498-502,504-9,512,514-6,521Lotze,264luck,399Lumen,407-8MacCullagh,150Mach,375Mach-Delage,276magnetism,149magnitude,49Mariotte's law,120,132,157,342,524Maros,203mass,98,312,446,486,489,494,515mathematical analysis,218continuum,46creation,383induction,40,220physics,136,297,319mathematics,369,448matter,492Maupertuis,535,537-8Maurain,543Maxwell,140,152,175,177,181,193,282-3,298,301,304-5,351,503,524-5Maxwell-Bartholi,309,503-4,519,521Mayer,119,123,300,312,318measurement,49Méchain,539-40mechanical explanation,177mass,312mechanics,92,444,486,496,512anthropomorphic,103celestial,279statistical,304Méray,211metaphysician,221meteorology,398mice,277Michelson,306,309,311,316,498,500-1milky way,523-30Mill, Stuart,60-1,453-4Monist,4,89,464moons of Jupiter,233Morley,309motion of liquids,283of moon,28of planets,341relative,107,487without deformation,236multiplication,36muscular sensations,69Nagaoka,317nature,127navigation,289neodymium,333neomonics,283Neumann,181Newton,85,96,98,109,153,291,370,486,516,536,538Newton's argument,108,334,343law,111,118,132,136,149,157,233,282,292,512,514-5,518,525principle,146,300,308-9,312no-class theory,478nominalism,28,125,321,333,335non-Euclidean geometry,55,59,388language,127space,55,235,237straight,236,470world,75number,31big,88imaginary,283incommensurable,44transfinite,448-9whole,44,469objectivity,209,347,349,408optical illusions,202optics,174,496orbit of Saturn,341order,385orientation,83osmotic,141Padoa,463Panthéon,414parallax,470parallels,56,443Paris time,233parry,419-22,427partition,45pasigraphy,456-7Pasteur,128Peano,450,456-9,463,472Pender,490pendulum,224Perrier,541Perrin,195phosphorus,333,468,470-1physical continuum,46physics,127,140,144,279,297physics of central forces,297of the principles,299Pieri,11,203Plato,292Poincaré,473point,89,244Poncelet,215postulates,382potential energy,116praseodymium,333principle,125,299Carnot's,143,151,300,303-5,399Clausius',119,123,143Hamilton's,115Lavoisier's,300,310Mayer's,119,121,123,300,312,318Newton's,146,300,308-9,312of action and reaction,300,487,502of conservation of energy,300of degradation of energy,300of inertia,93,486,507of least action,118,300of relativity,300,305,498,505Prony,445psychologist,383Ptolemy,110,291,353-4Pythagoras,292quadrature of the circle,161qualitative geometry,238space,207time,224quaternions,282radiometer,503radium,312,318,486-7Rados,201Ramsay,313rational geometry,5,467reaction,502reality,217,340,349Réaumur,238recurrence,37Regnault,170relativity,83,305,417,423,498,505Richard,477-8,480-1Riemann,56,62,145,212,239,243,381,432surface,211,287Roemer,233Röntgen,511,520rotation of earth,225,331,353roulette,403Rowland,194-7,305,489Royce,202Russell,201,450,460-2,464-7,471-4,477-82,484-5St. Louis exposition,208,320Sarcey,442Saturn,231,317Schiller,202Schliemann,19science,205,321,323,340,354Science and Hypothesis,205-7,220,240,246-7,319,353,452semicircular canals,276series, development in,287Fourier's,286Sirius,226,229solid bodies,72space,55,66,89,235,256absolute,85,93amorphous,417Bolyai,56Euclidean,65geometric,66Lobachevski's,239motor,69non-Euclidean,55,235,237of four dimensions,78perceptual,66,69tactile,68,264visual,67,252spectra,316spectroscope,294Spencer,9sponge,219Stallo,10stars,292statistical mechanics,304straight,62,82,236,433,450,470Stratonoff,531surfaces,58systematic errors,171tactile space,68,264Tait,98tangent,51Tannery,43teaching,430,437thermodynamics,115,119Thomson,98,488thread,104time,223equality,225local,306,307measure of,223-4Tisserand,515-6Tolstoi,354,362,368Tommasina,519Transylvania,203triangle,58angle sum of,58truth,205Tycho Brahe,133,153,228unity of nature,130universal invariant,333Uriel,203van der Waals,153Vauban,210Veblen,203velocity of light,232,312Venus of Milo,201verification,33Virchow,21visual impressions,252space,67,252Volga,203Voltaire,537-8Weber,117,515-6Weierstrass,11,212,432Whitehead,472,