Virginia meteorite, see [Meteorites] and [Meteoric iron.]

— gold mines, see [Gold].

— salt formation, xxiv, 51; xxix, 84, 113; xli, 214; xliv, 173.

—, geological remarks on, i, 60, 214, 317.

— tertiary formation, xi, 54; xxxviii, 183.

—, coal of, see under [Coal.]

—, geological report of W. B. Rogers, noticed, xxxii, 192; xxxvii, 380.

Virtual velocities, principles of, T. Strong, xlii, 66; xliii, 77.f

Virus, vaccine, liable to lose virtue, xxxviii, 175.