Alger, F., formula of Masonite, xlviii, 218.
Allen, Z., on the Providence tornado, xxxviii, 74; xliii, 137, 264.
America and Asia, Arctic Geology of, xvii, 1.
Ashes, volcanic, of Etna, analysis of, xii, 194.
—, —, transported by winds, xxv, 129.
Bache, A. D., on electro-magnetic experiments, xxii, 409.f
—, on American Meteorology, xxxviii, 95.
—, rapid corrosion of a chain cable, xxxviii, 176.
—, observations on magnetic dip, xl, 374.
—, magnetic intensity in Europe, xl, 30.