VI TABLE OF CONTENTS. 



by the Microscopic Fhotograph, 128; Chemistry and Thermotics, 125; 

 Continuity of the Liquid and Gaseous States of Matter, 125; the Forces 

 developed by Evaporation and Condensation, 126 ; the Heat produced by 

 Galvanic Currents, 126; the Molecular Constitution of Gases and Liquids, 

 127 ; Compressibility of "Water, 145 ; the Friction and Thermal Conductiv- 

 ity of Gases, 169; the Connection between Fluorescence and Absorption, 

 170; the Isochronism of the Balance Spring, 171; Attraction, Repulsion, 

 and Radiation, 173 ; Rood's Application of Zollner's Horizontal Pendulum, 

 174; the Elasticity of Bars of Iceland Spar, 175; a New Manometer, 176; 

 the Physical Properties of Matter in the Liquid and Gaseous States, 176; 

 on the Influence upon the Movement of a Pendulum of a Fluid contained 

 in its Spherical Bob, 177; Flow of Air through Orifices, 186. 



Sound (see also p. xlix) : Reflection of Sound from a Layer of Flame or 

 Heated Gas, 128 ; New Method of Observing the Vibrations of a Tuning- 

 fork, 130 ; the Action of Organ-pipes, 131 ; Effect of the Movement of the 

 Observer on Sound and Light, 131 ; the Theory of Resonators, 132 ; Vibra- 

 tions of Membranes, 132 ; the Cause of Wolf in the Violincello, 179 ; the 

 Pyrophone, 179 ; Ancient Musical Instrument in China, 202 ; Remarkable 

 Improvements in Stringed Instruments, 203 ; Harmony in Musical Instru- 

 ments, 204. Fog-signals : the Gas-gun for Fog-signals, 129; Steam Fog- 

 whistles, 129 ; a New Fog-signal, 130 ; Relative Efficiency of Various Fog- 

 signals, 180; Fog-signals, 181. 



Light (see also Astronomy for Spectroscopy, and p. lix) : the Spectra 

 of the Least Fusible Metals, 133 ; the Cause of the Variation of Gaseous 

 Spectra, 133; a Simple Spectroscope for Stars, 133; the Beginnings of 

 Spectrum Analysis, 134 ; Spectra of Certain Rarer Metals, 134 ; Effect of 

 Temperature and Pressure on the Spectrum Lines, 135; New Tables of 

 Spectrum Lines, 135; Advantageous Construction of the Spectroscope, 

 136 ; Abbe's Refractometer, 136 ; the Cause of the Luminosity and Non- 

 luminosity of Flames, 136 ; Flame of Burning Glycerine, 137 ; a Perfectly 

 Monochromatic Sodium Flame, 137; an Apparatus for Illustrating the 

 Mechanical Effects of Light, 137 ; on the Intensity of the Light Reflected 

 from Glass, 138 ; the Fixed Stars as Visible through Minute Apertures, 

 139; the Opacity of Photographic Images, 140; on Wave Surfaces in 

 Optics, 140; on Optical Phenomena at the Transit of Venus, 142; the 

 Color of Diamonds, 144; Gilt-edged Prism in the Construction of the 

 Camera-lucida, 144; the Reflection of Light, 146; the Action of Light 

 upon Chlorophyl, 146; Experiments on the Velocity of Light, 147; 

 Automatic Registration of the Chemical Action of Light, 148; New Method 

 of Measuring the Velocity of Light, 149 ; the Power of the Electric Light, 

 150; Electric Light for Locomotives, 151; the Connection between Flu- 

 orescence and Absorption, 170; the Spectroscope with a Fluorescent Ocular, 

 138; Accidental or Subjective Colors, 189; Reflection of Thin Films, 191; 

 Elliptic Polarizations of Light, 140; a New Class of Absorption Phenomena, 

 141 ; the Phosphorescence of Phosphorus, 141 ; Great French Light-house 

 at La Havre, 149; the Roman Pharos in Dover Castle, 150; New Pho- 

 tometers, 145; on Celestial Photometry, 182; Recent Improvements in the 

 Microscope, 188; Testing Microscope Object-glasses, 189; on the Phenom- 

 ena of Diffraction Produced by Circular Not-work, 143. 



