—, sulphate of, in Massachusetts, i, 115; viii, 56.
—, —, in Connecticut, v, 36; viii, 260; x, 13.
—, —, in New York, iv, 250; xv, 243.
—, —, in New Jersey, v, 265.
—, titanic, near Baltimore, Maryland, T. G. Clemson, xvii, 42.
Irradiation, notice of B. F. Joslin's memoir on, xxvii, 389.
Ischil, salt mines of, xxix, 225.
Islands, floating, A. Pettengill, xii, 122.
—, sudden formation of, from volcanic action, G. Bischof, xxxvi, 267.
—, volcanic, near Sicily, thrown up, xxi, 399.f