Soils composed either principally, or almost entirely of heath soil, or of vegetable mould, although very highly recommended for the growth of the Cucumber in winter, are nevertheless objectionable when applied alone, as will be evident if the foregoing principles are taken into view: it cannot however be assumed that the plants will not grow in these soils, for they grow vigorously for a period; neither can it be asserted that such soils do not contain the qualities which are necessary to administer to the nutrition of plants, for it is scarcely possible to conceive any substances which are more nutritious, or whose application in this respect is more effectual; but they are objectionable, in consequence of their becoming soon expended, and failing to maintain for any length of time, an equable degree of moisture. The cause which tends to produce this effect, is the porosity, or the want of mechanical combination in the texture of the soil; which being highly favourable to evaporation, is liable to render it speedily, and very materially dry, when exposed to the influence of powerful solar heat: the frequent application of water, does not entirely obviate the objection, for even when so applied, it soon becomes again evaporated, and thus tends to deteriorate the soil, and decrease its fertility; this it does, by taking up much of the soluble matter contained in it, and conveying it by evaporation into the atmosphere, instead of its being taken up by the roots whilst in a fluid state, and applied to the plant as a means of nutrition: when it is thus conveyed to the atmosphere, the leaves though they are enabled to take up a portion of their food from thence, are still incapacitated to do so fully, and hence, much of the fertilizing properties of the soil, is carried off by the first current of air which passes through the structure; and the plants decline by reason of starvation, though they had been seated in the midst of plenty.