| § 1. | Secondary Current by Induction. No Increased E. M. F. | Faraday |
| 2. | Electric Spark and Increased E. M. F. by Induced Current. | Page |
| 3. | Spark in Secondary Increased by Condenser in Primary. | Fizeau |
| 4. | Atmosphere around an Incandescent Live Wire. | Vincintini |
| 5. | Magnetizing Radiations from an Electric Spark. | Henry |
| 6. | Arcing Metals at Low Voltage. | Faraday |
| 7. | Non-arcing Metals at High Voltage. Practical Application. | Wurts |
| 8. | Duration of Spark Measured. | Wheatstone |
| 8a. | Discharge—Intermittent, Constant, and Oscillatory—by Variation of Resistance. | Feddersen |
| 9. | Musical Note by Discharge with Small Ball Electrodes. Invisible Discharge. | Faraday |
| 9a. | Pitch of Sound Changed by Approach of Conductor Connected to Earth. | Faraday and Mayer |
| 10. | Brush Discharge. Color. StriÆ. Nitrogen Best Transmitter of a Spark, and its Practical Bearing in Atmospheric Lightning. Cathode Brushes in Different Gases. | Faraday |
| 11. | Glow by Discharge. Glow Changed to Spark. Motion of Air. Apparent Continuous Discharge during Glow. | Faraday |
| 12. | Spark. Solids Perforated. | Lullin |
| 13. | Spark. Glass Perforated. Holes Close Together. Practical Application for Porous Glass. | Fage |
| 14 and 14a. | Spark. Penetrating Power. Conducting Power of Gas. Relation of E. M. F. to Pressure of Gases. Discharge through Hydrogen Vacuum Continued with Less Current than that Required to Start it. | Knochenhaurer, Boltzmann, Thomson (Kelvin), Maxwell, Varley, Harris, and Masson |
| 15. | Dust Particles or Rust on the Electrodes Hasten Discharge. | Gordon |
| 16. | Where the Distance is Greater, the Dielectric Strength is Smaller, Both Distances Being Minute. | Thomson (Kelvin) |
| 17. | Discharge through Gases under Very High Pressures. Increased Dielectric Strength. | Cailletet |
| 18. | Discharges in Different Chemical Gases Variably Resisted. | Faraday |
| 19. | Gas as a Conductor. Molecule for Molecule, its Conductivity Greater than that for Gases. | Thomson, J. J. |
| 20. | Relation of Light to Electricity. The Square Root of the Dielectric Capacity Equal to the Refractive Index. | Boltzmann, Gibson, Barclay, Hopkinson, and Gladstone |
| 21. | Hermetically Sealed Discharge Tubes with Platinum Leading-in Wires. | PlÜcker and Geissler |
| 22. | Luminosity of Discharge Tubes Produced by Rubbing. Increased by Low Temperature. | Geissler |
| 23. | Different Vacua Needed for Luminosity by Friction and by Discharge. | Alvergniat |
| 24. | Phenomena of Discharge around the Edges of an Insulating Sheet. | Steinmetz |
| 25. | Highest Possible Vacuum Considered as a Non-conductor. | Morgan |
| Roentgen |
| 84. | X-rays Characterized. Fluorescence and Chemical Action. | Roentgen |
| 85. | Non-refraction of X-rays Determined by Opaque and Other Prisms. Refraction, if Any, Exceedingly Slight. | Roentgen |
| 86. | Velocity of X-rays Inferred to be the Same in All Bodies. | Roentgen |
| 87. | Non-double Refraction Proved by Iceland Spar and Other Materials. | Roentgen and Mayer |
| 88. | Rectilinear Propagation of X-rays Indicated by Pin-hole Camera and Sharpness of Sciagraphs. | Roentgen |
| 89. | Interference Uncertain Because X-rays Tested were Weak. | Roentgen |
| 90. | Electrified Bodies, whether Conductors or Insulators, or Positive or Negative, Discharged by X-rays. Hydrogen, etc., as the Intermediate Agency. | Roentgen |
| 90a. | Application of Principle of Discharge by X-rays. | Roentgen |
| 90A, b, c, d. | Supplementary Experiments on Charge and Discharge by X-rays. | Minchin, Righi, Benoist, Hurmuzescu, and Borgmann |
| 91. | Focus Tube. | Roentgen, Shallenberger, et al. |
| 91a. | Tribute to the Tesla Apparatus. | Roentgen |
| 92. | X-rays and Longitudinal Vibrations. | Roentgen |
| 93. | Longitudinal Waves in Luminiferous Ether by Electrical Means Early Predicted by | Thomson (Kelvin) |
| 94. | Theory as to X-rays Being of a Different Order of Magnitude from those so far Known. | Schuster |
| 95. | Longitudinal Waves Exist in a Medium Containing Charged Ions. Theoretical. | Thomson, J. J. |
| 96. | Practical Application of X-rays Foreshadowed. | Boltzmann |
| 97. | The Sciascope. | Magie, Salvioni, et al. |
