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tended, "that water, by virtue of the vital energy of the plant, was sufficient to form all the different substances contained in vegetables. The result of a great variety of experiments is, that water is not the sole food of plants, and is not convertible into the whole ingredients of the vegetable substance."
107. In the state of vapour, water is estimated to occupy 1400 times its original bulk, but its volume is increased to 1728 times when it exists in the state of visible steam. It is a permanently elastic fluid in the state of vapour, and as such, exists in the atmosphere, appearing to be incapable of again becoming fluid water, till it undergoes a change in its electric condition. "The conversion of bodies into the state of vapour, as well as the condensation of vapour, is generally attended by some alteration of their electrical condition; and the bodies in contact with the vapour are thereby rendered electrical. Thus, if a plate of metal strongly heated, be placed upon a gold-leaved electroscope, and water be dropped upon the plate, at the moment the vapour rises the leaves of the electroscope diverge with negative electricity. The general fact was noticed by Laplace, Lavoisier, and Volta, in the year 1781; and was found to extend both to solids and to liquids passing into gaseous form." "In general, it is found that the vaporization of water, by simple ebullition, produces negative electricity in the remaining fluid, or vessel, which contains it: the vapour itself being positive. On the contrary, when aqueous vapour is condensed into water, it becomes negative, leaving the bodies with which it was last in contact in a state of positive electricity."—Treatise on Electricity, of the Library of Useful Knowledge, p. 55.
As vapour is considered one of the constituents of atmospheric air, it cannot, with propriety, become a subject of investigation in the present section. Enough has now been said to afford satisfactory evidence, that water, whether it be considered as a mild and bland fluid, or as a decomposable medium, exhibiting the most tremendous phenomena, is of so much importance in the economy of creation, as to establish its right to take rank as second only, among the most influential agents of nature.
NATURAL HISTORY AND CULTIVATION OF ESCULENT
OF THE CABBAGE TRIBE,
Subject 1. Biussica Oleracea. Cruciferce. Class xv. Order ii. Tetradynamia Siliquosa, of Linnaeus. Capitata eliptica, of Decandolle.
108. The cabbage is one of the most ancient of our esculent vegetables; the tribe includes an extensive assortment of varieties and subvarieties, all, probably, proceeding from one common origin. Some of these must have been known in the time of the Saxons, as White, in his "Natural History of Selborne," says that they named the month of February "sprout-kale.'' It appears probable that the Romans introduced the Italian cabbage into South Britain. The native cabbage grows wild on the sea-shore of different parts of England; it is a biennial, and flowers in May and June. The leaves are glaucous, (sea-green,) rather fleshy, very smooth; lower ones large, lyrate, (lyre-shaped,) waved; the upper ones oblong, toothed, or nearly entire. Flowers in longish clusters, bright lemoncolour. CaZy-r-leaves a little spreading, but straight; close at the bottom. Pods cylindrical, smooth, without a beak. Seeds large and globose. (smith's Fug. Flora; also, Enc. of Gard., Brassica.)
109. Var. I. Common white cabbage, Br. oler. var. capitata, produces firm white heads, green, or greenish yellow externally, but white within. It contains about twenty sub-varieties, of which the best and most suitable to moderate sized gardens, are the
Early York, dwarf, Pownton,
London medium, Varrack,
Sugar-loaf, early, Battersea, early.
As the cabbage is a biennial, the chief or early summer crop is to be sown in the preceding autumn; but the later summer and autumn crops, to come in from July to the end of the year, must be the first noticed, and the directions will be given very particularly.
110. Spring sowing. Towards the close of March, during April, and even early in May, cabbage seed may be sown: the quantity, and frequency of repetition must depend upon the consumption; but with good management, one sowing in April will furnish an abundant supply for a family of eight or ten persons. Prepare a spot of ground of sufficient extent to admit of three or four drills, of about fifteen feet long, for each sort of cabbage that may be preferred. This ground need not be manured, but it should be well digged and finely pulverized. Set the line about nine inches within the edge of the bed, and draw a drill an inch deep, as straight and true in depth as possible; then make the bottom of the drill firm and even by pressing a long round pole upon it; or by beating it with the back of a wooden-headed rake. Sprinkle the seeds evenly, but not very thickly, along the drill. Make another drill about nine inches from the former, and so proceed with one sort of seed till enough of that be sown; then draw the loose earth into each drill, and press it firmly upon the seed with the spade. Proceed thus with every variety, and between each bed a path of full fifteen inches (in addition to the nine inches on each side of the drills) should be allowed. Mark with a stick, or cutting, the boundaries of each variety; cut the edges of the little beds perfectly even, and then dress the surface with the back of the rake. The earlier and dwarf sorts may be sown in March; the later and large sorts in April; but it will be prudent to begin early, as the seed sometimes fails. Keep every variety quite separate. When the plants appear, thin them to about an inch apart; and shortly afterwards clear the beds of weeds with the Dutch hoe; for this purpose choose a sunny day, as the heat will speedily kill the weeds; do not, however, trust to that, but rake off every weed as each bed is hoed. As the plants advance, thin them to two inches apart; and when they have three leaves, two inches broad, prepare a nursery bed for each sort, about four feet wide by twenty-five feet long. Spread some rich compost manure on the surface, and then dig it well in, breaking the earth very fine, the whole length of the bed, but only to the breadth of two feet. Mark the outer edge of the bed, and at nine inches from that edge stretch the line tightly. Raise the plants one by one with a setting-stick, or the garden trowel, and select plants as nearly of a size as possible. Set about forty in the row, by the plantingstick, or trowel, and let the earth be brought close round the roots and stems, and as high nearly, as the base of the lower leaf. Set out the plants six inches apart, and when one or two rows are planted, dig another space for two more rows, and proceed thus till six rows be completed; then cut the edges of the bed smooth and even by the line, at nine inches from each outer row. Give each plant a quarter of a pint of soft water, pouring it into the hole from the spout of a pot held nearly close to the stem. Fine pulverization
is assuredly the greatest security for successful planting; and if the evening be chosen for the time of pricking out, repeated watering need seldom be resorted to. It will be remarked, that I have directed the bed to be digged by portions; most persons do the whole digging before they begin to plant. I have adopted and recommended the above plan, to prevent the evil of treading on ground that has been worked. There will now be 240 plants in six rows, and the bed will be four feet wide; after which, a small footpath cut out, and made level between this first bed and another piece of ground, will give space enough for the due separation of the several sub-varieties of the plants. By observing these directions, (which will apply to savoys, borecole, and broccoli,) a double object is attained; 1st, the nursery beds are set out with precision and neatness; and 2nd, the ground is not [trodden into holes; which it always must be, when the digging is finished in the first instance. If the weather be very dry, the new beds will require two or three waterings early in the mornings, or after sunset; and should any plant fail, it must be replaced by another from the seed bed. If a considerable number of plants still remain in these seed beds, it will be prudent to raise them all with the trowel, and reset them by the line in regular distances of eight or nine inches apart, in their own ground. This operation will give the plants a check, and prevent them from acquiring long forked roots and straggling stems; the roots will become fibrous, or stocky, and the plants will be in regular order and ready to be set out, when those in more manured ground will be advancing to the state of cabbages. As the plants in the nursery-beds increase in size, transplant them at different periods of May, June, and July. Set out, and dig the beds as directed above, raise the alternate plants of the nursery-beds, and plant them in the new beds, where they are to remain. As to distances, the smaller sorts should stand twelve inches, the middlingsized sixteen inches, and the large Yorks, sugar-loaf, &c. from two feet to thirty inches apart, every way. Whenever plants are set out, whether it be with the dibber, the trowel, or the spade, the utmost care must be taken to bring the earth close to the bottom, and about every part of the roots; and if these roots be covered with knobs or tubercles, they must be trimmed with a knife, to remove all the excrescences; and if there be good fibres above the injured part, the whole below the fibres, should be pruned off. Set each plant as deep as the butt or base of the lower leaves; hold it in the left hand, work the planting tool about the roots, till it so press the earth about them, that the plant will resist a gentle pull; and then, all being secure, make the ground neat. This neatness can always be produced by an adroit use of the garden trowel at the time of planting; patting and smoothing the soil without pressure, about and around each plant; method and experience, by the aid of a quick discerning eye, will effect any thing.
In the seed-beds the plants, if kept clean and hoed, will, at various periods, be fit for transplanting; and thus by management of the three departments, that is, of the seed-beds, the nursery-beds, (the plants in which should from time to time be thinned till they stand at from twelve to sixteen inches apart, or more, according to the sort,) and of the transplanted cabbage-beds, there will be a constant and various supply for the table from May to November or December. In fact, from the seed-beds, by transplanting as late as September and October, I have had delicious cabbages; not large, but firm, clear, and green, in the following spring.
111. The main crops of what are termed summer cabbage, must be managed somewhat differently; and observe, that very nice attention must be paid to the period of sowing, for if that be too early, the plants may run to seed, and if too late, they can hardly acquire sufficient strength in time to become early cabbage: the last week in July, and the first week in August afford, pretty nearly, the limits for this operation; so experience has determined. The early York alone, or the early York and London, and early sugar-loaf, and Downton, may be sown as directed for the spring sowing; the subsequent management is to be the same, and at the final transplantings, the plants may stand at similar distances. In September, the nursery-beds should be made, and the plants finally placed out in October and November. If the winter prove mild, and the ground be in good heart, this mode will bring firm good cabbages in April and May; but as the season may prove severe, it will be safer to leave the greater part in seed and nursery-beds; for if severe frosts occur, the small space occupied by the plants therein can be easily protected by coverings of fern leaves, long litter, or branches of evergreens. The plants so treated, are to be finally set out in February and March in rich earth. If the weather prove very mild in November, or indeed at any period betwixt November and February, the plants finally set out, may become too forward; to prevent that, raise them up with a spade, and reset them in the same spot immediately. Hoe the seed and nursery-beds, so as to kill all weeds: and as to the cabbage-beds, dig deeply once or twice in dry weather, those in which the plants stand at the greatest distances; and hoe those in which the plants stand too close to each other to admit of digging; draw earth also to the stems of the plants, particularly when the cabbages begin to form their heads: