Vacuum, Boyle's argument on the cause of a, 23.
Velocity of electricity, 93;
of light measured by Roemer, 2;
of light deduced from electro-magnetic theory, 306.
Viscosity of gases explained by Maxwell, 299.
Voltaic pile constructed by Faraday, 241.
Vortex theory of matter, 312.
Voss machine, 316.