Perrine, H., on the Agave and other plants used for cordage, xxv, 330.
Perry, T. H., magnetic dip in different regions, xlvii, 84.
—, method of adjusting the dipping needle, xxxvii, 277.
—, on some of the probable effects of a resisting medium, xxxviii, 246.
Persoon, obituary notice of, xxxii, 215.
Peru, Andes of, xviii, 182.
—, —, highest elevations of, xviii, 184.
—, —, highest habitations of men in, xviii, 183.
—, —, trachytes of, xviii, 183.
—, —, the mining regions of, xvii, 43.