A.

• Air, 11, 15, 28, 50, 136.
• Air-pump, 31, 145.
• Angle, 44.
  • acute, 44.
  • obtuse, 44.
  • right, 44.
  • of incidence, 45, 154, 160, 173.
  • of reflection, 45, 154, 160, 173.
  • visual, 168, 169, 170.
• Angular velocity, 171.
• Antarctic circle, 92.
• Aphelion, 75.
• Arctic circle, 92.
• Atmosphere, 28, 104, 129, 136, 144, 150, 163.
  • colour of, 193.
  • reflection of, 193.
  • refraction of, 182.
• Attraction, 10, 14, 23, 25, 179.
  • of cohesion, 15, 19, 118.
  • capillary, 18.
  • of gravitation, 18, 23, 29, 70, 80, 96, 116, 136.
• Avenue, 170.
• Auditory nerve, 151.
• Axis, 78.
  • of motion, 48.
  • of the earth, 22, 99.
  • of mirrors, 176.
  • of a lens, 184.

B.

• Balloon, 30.
• Barometer, 140.
• Bass, 155.
• Bladder, 138.
• Bodies, 10.
  • elastic, 40.
  • fall of, 23, 26, 30, 36.
  • luminous, 157.
  • opaque, 157.
  • sonorous, 152, 155.
  • transparent, 157.
• Bulk, 16.

C.

• Camera obscura, 184, 197, 201.
• Capillary tubes, 18.
• Centre, 48.
  • of gravity, 48, 51, 52, 115.
  • of magnitude, 48, 53.
  • of motion, 48, 55, 115.
• Centrifugal force, 49, 72, 95, 115.
• Centripetal force, 49, 72.
• Ceres, 84.
• Circle, 44, 94.
• Circumference, 94.
• Clouds, 129.
• Colours, 23, 185.
• Comets, 86.
• Compression, 42.
• Concord, 155.
• Constellation, 86.
• Convergent rays, 175, 177.
• Crystals, 12.
• Curvilinear motion, 47, 72.
• Cylinder, 52.

D.

• Day, 78, 105, 106.
• Degrees, 44, 94, 99, 169, 170.
  • of latitude, 94, 112.
  • of longitude, 94, 112.
• Density, 16.
• Diagonal, 47.
• Diameter, 94.
• Discords, 155.
• Diurnal, 78.
• Divergent rays, 175, 177.
• Divisibility, 10, 12.

E.

• Earth, 18, 70, 84, 88, 95.
• Echo, 154.
• Eclipse, 110, 159.
• Ecliptic, 86, 92, 99.
• Elasticity, 41.
• Elastic bodies, 28, 40.
  • fluids, 28, 41, 118, 136.
• Ellipsis, 75.
• Equinox, 100, 107.
  • precession of, 107.
• Equator, 92, 99.
• Essential properties, 10.
• Exhalations, 13.
• Extension, 10, 11.
• Eye, 166, 195.

F.

• Fall of bodies, 24, 27, 31.
• Figure, 10, 12.
• Fluids, 118, 128.
  • elastic, 28, 41, 118, 136.
  • equilibrium of, 120, 122, 132.
  • non-elastic, 119.
  • pressure of, 121.
• Flying, 40.
• Focus, 176.
  • of concave mirrors, 177.
  • of convex mirrors, 175, 177.
  • of a lens, 184.
  • imaginary, 176.
  • virtual, 176.
• Force, 33.
  • centrifugal, 49, 72, 95, 115.
  • centripetal, 49, 72.
  • projectile, 47, 49.
  • of gravity, 47, 49.
• Fountains, 135.
• Friction, 68, 69, 135.
• Frigid zone, 93.
• Fulcrum, 54.

G.

• General properties of bodies, 10.
• Georgium Sidus, 85.
• Glass, 183.
  • burning, 188.
  • refraction of, 183.
• Gold, 119, 126.
• Gravity, 18, 23, 78, 97.

H.

• Harmony, 155.
• Heat, 16, 29, 103.
• Hemisphere, 92, 100.
• Herschel, 85.
• Hydraulics, 118.
• Hydrometer, 128.
• Hydrostatics, 118.

I.

• Image on the retina, 165, 172.
  • reversed, 167.
  • in plain mirror, 172.
  • in concave do. 175.
  • in convex do. 175.
• Impenetrability, 10.
• Inclined plane, 54, 66.
• Inertia, 10, 14, 32.
• Inherent properties, 10.
• Juno, 84.
• Jupiter, 85.

L.

• Lake, 133, 135.
• Latitude, 94, 112.
• Lens, 184.
  • concave, 184.
  • convex, 184.
  • meniscus, 184.
  • plano-concave, 184.
  • plano-convex, 184.
• Lever, 54, 55.
  • first kind, 58.
  • second kind, 60.
  • third kind, 60.
• Light, 157.
  • pencil of, 158.
  • of the moon, 162, 163.
  • absorption of, 188.
  • reflected, 160.
  • refraction of, 179.
• Liquids, 118.
• Longitude, 94, 112.
• Luminous bodies, 157.
• Lunar month, 108.
  • eclipse, 110.

M.

• Machine, 54, 66.
• Magic lanthorn, 203.
• Mars, 84.
• Matter, 10, 13.
• Mechanics, 32.
• Mediums, 157, 180.
• Melody, 156.
• Mercury, (planet) 83, 85, 114.
• Mercury, or quicksilver, 16, 140, 141.
• Meridians, 93.
• Microscope, 200.
  • single, 200.
  • double, 200.
  • solar, 202, 203.
• Minerals, 12.
• Minutes, 94.
• Momentum, 38, 56.
• Monsoons, 149.
• Month, lunar, 108.
• Moon, 78, 79, 80, 82, 85.
• Moonlight, 162, 163.
• Motion, 14, 32, 36.
  • accelerated, 36.
  • axis of, 48.
  • centre of, 48, 55.
  • compound, 46.
  • curvilinear, 47, 49.
  • diurnal, 78.
  • perpetual, 35.
  • retarded, 35.
  • reflected, 43.
  • uniform, 34.
• Mirrors, 172.
  • axis of, 176.
  • burning, 177.
  • concave, 174, 176, 209.
  • convex, 174, 175.
  • plane or flat, 172.
  • reflection of, 173.

N.

• Neap tides, 116.
• Nerves, 166.
  • auditory, 151, 166.
  • olfactory, 166.
  • optic, 164, 166.
• Night, 78.
• Nodes, 110.

O.

• Octave, 156.
• Odour, 13.
• Opaque bodies, 157, 158.
• Optics, 157.
• Orbit, 86.

P.

• Pallas, 84.
• Parabola, 51.
• Parallel lines, 25.
• Parallel of latitude, 94.
• Pellucid bodies, 157.
• Pencil of rays, 158.
• Pendulum, 98.
• Perihelion, 75.
• Perpendicular lines, 25.
• Phases, 109.
• Piston, 143, 145.
• Plane, 92, 93.
• Planets, 76, 81, 83.
• Poles, 92, 99, 100.
• Polar star, 100, 112.
• Porosity, 42, 126.
• Powers, mechanical, 54.
• Projection, 49, 50, 71.
• Precession of equinoxes, 107.
• Pulley, 54, 63.
• Pump, 31.
  • sucking and lifting, 143.
  • forcing, 144, 145.
  • air, 31, 145.
• Pupil of the eye, 164.

R.

• Rain, 17, 129.
• Rainbow, 188.
• Rarity, 16.
• Ray of light, 158, 179.
  • reflected, 160, 161.
  • incident, 161.
• Rays, intersecting, 165.
• Reaction, 39.
• Receiver, 31.
• Reflection of light, 160, 163.
  • angle of, 45, 161, 173.
  • of mirrors, 173.
  • of plane mirrors, 174.
  • of concave do. 174.
  • of convex do. 174.
• Reflected motion, 43.
• Refraction, 179, 186.
  • of the atmosphere, 182.
  • of glass, 183.
  • of a lens, 184.
  • of a prism, 185.
• Resistance, 54.
• Retina, 165.
  • image on, 166.
• Rivers, 134.
• Rivulets, 131.

S.

• Satellites, 80, 111, 113.
• Saturn, 85.
• Scales, or balance, 55.
• Screw, 54, 67.
• Shadow, 110, 111.
• Siderial time, 106.
• Sight, 165.
• Signs of the zodiac, 86, 93.
• Smoke, 14, 29.
• Solar microscope, 202.
• Solstice, 100, 102.
• Sound, 151.
  • acute, 155.
  • musical, 155.
• Space, 33.
• Specific gravity, 123.
  • of air, 140.
• Spectrum, 190.
• Speaking-trumpet, 154.
• Sphere, 26.
• Springs, 130.
• Spring tides, 116.
• Square, 81, 85.
• Stars, 77, 86, 102.
• Storms, 147.
• Substance, 10.
• Summer, 76, 100.
• Sun, 71, 75, 78, 162, 182.
• Swimming, 41.
• Syphon, 132.

T.

• Tangent, 49, 73.
• Telescope, 203, 204.
  • reflecting, 204.
  • refracting, 204.
• Temperate zone, 92, 101.
• Thermometer, 142.
• Tides, 114, 116.
  • neap, 116.
  • spring, 116.
  • Ærial, 150.
• Time, 105, 107.
  • siderial, 107.
  • equal, 107.
  • solar, 107.
• Tone, 155.
• Torrid zone, 93, 147, 182.
• Transit, 114.
• Transparent bodies, 157.
• Treble and bass, 155.
• Tropics, 92.

V.

• Valve, 143.
• Vapour, 17, 29, 104, 129.
• Velocity, 33, 57.
• Venus, 84.
• Vesta, 84.
• Vibration, 98, 152.
• Vision, 164, 168.
• Vision, angle of, 168, 170.
  • double, 171.

U.

• Undulation, 153.
• Unison, 155.

W.

• Water, 118, 130.
  • spring, 130.
  • rain, 130.
  • level of, 120.
• Wedge, 54, 66.
• Weight, 23.
• Wheel and axle, 54, 65.
• Wind, 146.
  • trade, 147.
  • periodical, 148.
• Winter, 76, 101.

Y.

• Year, 107.
  • siderial, 107.
  • solar, 107.

Z.

• Zodiac, 86.
• Zone, 93.
  • torrid, 93, 147, 182.
  • temperate, 93, 101.
  • frigid, 93, 100.

THE END.

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