— water, effect from, in a Leyden jar, viii, 374.
— —, by the aid of sulphuric acid, apparatus for, R. Hare, xxvii, 132.f
Frodsham, W. J., on the vibration of pendulums with different suspending springs, xxxvii, 278.
—, elected a member of the Royal Society, xxxvi, 195.
Frogs, introduction of, into Ireland, xxviii, 398.
—, in rocks, remarks on, D. Thomas, xix, 167.
Fromont garden, account of, xx, 83.
Frozen wells, xxxvi, 184.
Fruit, method of preserving without sugar, xv, 381.
—, fossil, of Zamia, &c., G. A. Mantell, xlv, 401.