—, organic matter of, C. T. Jackson, xlv, 337.
—, on the importance of determining the organic constituents of, and the mode, C. Daubeny, xliv, 352.
—, state of iron in, xlix, 394.
—, action of manures on, Boutigny d'Evreux, xxvi, 179.
—, action of gypsum on, xxvi, 181.
—, effect of magnesia on, xli, 159.
—, effect of hydrated-peroxide of iron on, xli, 159.
—, effect of sulphuret of iron on, xli, 159.
—, potash in, xli, 160.
—, in Indiana, J. T. Plummer, xl, 198; xliv, 310.