CONTENTS.

Article		Page
760.	Weber's method using transient original: "transient currents"; brief pulses of electricity currents .. .. .. .. .. ..	360
761.	His method of observation .. .. .. .. .. .. .. ..	361
762.	Weber's method by damping original: "damping"; the process of reducing the oscillation of a needle .. .. .. .. .. .. .. ..	361
763.	Thomson's William Thomson, later Lord Kelvin method using a revolving coil .. .. .. .. .. ..	364
764.	Mathematical theory of the revolving coil .. .. .. .. ..	364
765.	Calculation of the resistance .. .. .. .. .. .. ..	365
766.	Corrections .. .. .. .. .. .. .. .. .. .. ..	366
767.	Joule's calorimetric original: "calorimetric"; measuring heat produced by an electric current method .. .. .. .. .. .. ..	367

CHAPTER XIX.

Article		Page
768.	Nature and importance of the investigation .. .. .. ..	368
769.	The ratio of the units is a velocity .. .. .. .. ..	369
770.	Current by convection original: "convection"; the transfer of electricity by the movement of charged matter .. .. .. .. .. .. .. ..	370
771.	Weber and Kohlrausch's method .. .. .. .. .. ..	370
772.	Thomson's method by separate electrometer and electrodynamometer .. .. .. .. .. .. .. .. .. ..	372
773.	Maxwell's method by combined electrometer and electrodynamometer .. .. .. .. .. .. .. .. .. ..	372
774.	Electromagnetic measurement of the capacity of a condenser original: "condenser"; a modern capacitor. Jenkin's method .. .. .. .. .. .. .. ..	373
775.	Method by an intermittent current .. .. .. .. ..	374
776.	Condenser and "Wippe" original: "Wippe"; a German term for a switching device or "see-saw" commutator as an arm of Wheatstone's bridge ..	375
777.	Correction when the action is too rapid .. .. .. ..	376
778.	Capacity of a condenser compared with the self-induction of a coil .. .. .. .. .. .. .. .. .. .. ..	377
779.	Coil and condenser combined .. .. .. .. .. ..	379
780.	Electrostatic measure of resistance compared with its electromagnetic measure .. .. .. .. .. .. .. ..	382

Article		Page
781.	Comparison of the properties of the electromagnetic medium with those of the medium in the wave original: "undulatory" theory of light	383
782.	Energy of light during its propagation .. .. .. ..	384
783.	Equation of propagation of an electromagnetic disturbance ..	384
784.	Solution when the medium is a non-conductor .. .. ..	386
785.	Characteristics of wave-propagation .. .. .. .. ..	386
786.	Velocity of propagation of electromagnetic disturbances ..	387
787.	Comparison of this velocity with that of light .. .. ..	387