— magnesian hydrate of silica, P. T. Tyson, xviii, 79.
— — ibid, C. U. Shepard, xviii, 81.
— magnesite, hard, of Baumgarten, vii, 368.
— manganese ores, M. Berthier, vii, 366.
— marl from Farmington, Ct., E. Hitchcock, xxxvi, 176.
— — from New Jersey, xvii, 277.
— — from Ashley river, S. Carolina, J. L. Smith, xlviii, 101.
— marmolite, T. Nuttall, iv, 17, 19.
— Masonite, C. T. Jackson, xl, 186; xlviii, 218.
— melanite of Franklin furnace, N. J., H. Seybert, viii, 300.