given by the different chemical authorities, as shown in the table, are very striking.

Those in the water and vegetable fibre, divisions 2 and 3, may probably have arisen from actual differences in the dryness of the articles analyzed, or in the amount of their exterior coating, as might very naturally occur in several of the grains.

Those found in the percentage of oily matter, division 4, may perhaps be accounted for by supposing the analysts to have experimented upon different varieties of the same crop; thus, to take Corn as an example, it is perfectly comprehensible how neither Liebig nor any other chemist could find even five per cent. of oily matter in our light flour Corns, which seem to resemble Buckwheat in their character, while Dumas and others might readily obtain nine or ten per cent. from a strong northern yellow Flint Corn.

This division properly belongs with No. 5, the elements in both being carbonaceous, but I have given the oily matter a separate division, because, as the ready-formed fat in food is most easily appropriated, and, withal, renders important aid in digestion, the amount of this material found in a given crop affords a measurable test of its relative value in the fattening of animals.

The differences found in the percentages of the other carbonaceous and the nitrogenous elements, divisions 5 and 6, may be due, in part, to the same cause as those of the oily matter, but probably still more to differences of character and quality, independent of variety of stock, arising from differences in the feeding and culture of the particular crops from which the specimens were derived. The manure from a barnyard that is very thoroughly leached into the neighboring brook will not have much material to give stamina and richness to the crop to which it is applied; and if, in addition to this, the season's culture be slighted, a crop relatively rich in vegetable fibre, and poor in the more important constituents, may be reasonably expected.

The variations in the percentages of saline or inorganic elements, division 7, may be traced to the same or analogous It is well settled that plants, like animals, feed not

causes.

always upon that which is most desirable and proper, but upon what can be had in their season of need. If, therefore, the rains have carried off the elements of this and the two preceding divisions from the barn-yard, and they have been previously largely cropped out of the soil and sold off without return to the land, no grand and heavy crop can be expected.

Under the general terms saline or inorganic elements are included, in very various proportions, Silica or Flint, Lime, Magnesia, Alumina, Potash, Soda, metallic Oxides, Phosphoric and Sulphuric Acids, Chlorine, and a few other constituents; and, though their aggregates, as shown in this division, are small as compared with those of Nos. 5 and 6, yet they are, more or less of them, essential to every crop, and can not be taken by the plant from the atmosphere, whence much of the material for the others may probably be derived. Hence this division becomes of special importance, showing as it does the total amount of the privation which land sustains by the loss of these elements in a given crop.

By far the greater portion of these aggregates, however, are derived from about one half of the elements named above. Of the 24 lbs. of inorganic matter given in the table as obtained from the product of an acre of wheat, about 81⁄2 lbs. may be Silica, 2 lbs. Lime, 2 lbs. Magnesia, 4 lbs. Potash, and 5 lbs. Soda; and of the 240 lbs. yielded by the straw, about 189 lbs. may be reckoned as Silica, 16 lbs. Lime, 2 lbs. Magnesia, 14 lbs. Potash, and 2 lbs. Soda, with some 10 lbs. Phosphoric Acid; the small remaining balance in both being composed of minute portions of the other elements. The large predominance of silica and lime is a remarkable feature in this division, and may illustrate the natural law by which supply and demand are regulated in the vegetable and animal kingdoms. Without the silica, neither corn, grain, nor grass would stand upright to maturity; it forms the outer coating and strengthener of the stem of these and certain other plants, and may, without impropriety, be said to furnish to them the bones of vegetable growth. The lime is equally essential to the formation and strength of animal bones, of which it constitutes so large a part. Extraordinary means are sometimes used to

Y

supply the lack of it when the bones are in the forming state; thus the peasant mothers of Germany are said to give limewater to their young children; and when, in raising calves by hand, milk is economized by the use of hay-tea, &c., it is a custom, which I think is immemorial, to make up the great defect of the infusion by giving them chalk to lick, with which they instinctively supply the necessities of the animal economy. From the multiplicity of these saline or inorganic constituents of vegetables and their importance, although many are minute in quantity, it is apparent that very light applications of such manures as are rich in these elements may be of essential service to the crop.

A glance at the table shows that hay, and stalks, and straw contain more of saline or inorganic matters than is found in the grains, and the same is true of the vines of peas, potatoes, &c., which are omitted; to preserve all these with care, and return them, with suitable additions, to the soil, may therefore be regarded as one of the first duties of the intelligent cultivator.

Where, as in the case of tobacco, almost the whole product is of necessity sent away, the soil must be speedily exhausted, unless the various elements contained in the crop are replaced by importation, or by taxing other crops for a supply; but, in reference to ordinary farm soils and crops, the case is somewhat different. The elements contained in the various crops above enumerated may all be replaced, and the general condition of the farm progressively improved by the accumulations of a well-managed barn-yard, with the use of ashes, gypsum, marl, and swamp-muck treated with lime, where these are obtainable; but especially may this be effected by the frequent and regular use of clover as green manure; this, with the application of gypsum and occasional dressings of lime, will be found the cheapest and easiest known mode of resupplying the draughts made by the various crops, and sustaining and improving the strength and productiveness of the soil.

ADDENDUM.

Forcing Vegetables and Fruits.-Training Fruit-trees.

FORCING AND TRAINING.

FORCING common garden vegetables and forcing or training ordinary fruit-trees are modes of culture not likely to be very generally adopted in American home gardens; but, inasmuch as they may occasionally be fancied or found desirable, the following brief account of their objects and modes is introduced here as an addendum to the more valuable and important processes described in the body of the book.

FORCING.

FORCING is the general term descriptive of the various processes for raising vegetables, fruits, or flowers out of their natural or ordinary seasons or climates, by means of carefully-applied artificial heat under glass, whether in hot bed, or pit, or grapery, or orchard-house, or green-house, or dwelling.

Among gardeners, success in forcing is an object of ambition, and its honors are worn with a good deal of professional pride. Some affect to have peculiar modes of practice, which they hide carefully from others, but which are often mere worthless conceits.

It will be apparent to any observant mind that crops which in ordinary culture bear without injury the common vicissitudes of climate in the open air may easily endure the lighter and less frequent changes to which they are subjected in house or frame culture, unless a most unnatural system is pursued, or great carelessness displayed in their treatment.

The beau ideal of forcing is to create artificially a climate so perfectly resembling that which is natural and congenial to the plants forced as to induce fair vigorous growth and fruiting under a system of treatment not differing materially in other re

spects from high out-door culture. To effect this the chief thing is to give incessant care to the degree of temperature and moisture which the crop may require, and so to limit the quantity of fruit permitted to set as to keep it always somewhat below the bearing capacity of the tree, of which every gardener is supposed to be capable of judging at a glance, and every cultivator may learn to judge by a few careful experiments in fruiting. He can scarcely err injuriously except on one side. If he leave an excess of fruit upon the tree, the whole crop may be injured or destroyed, but if he reduce the amount, even much below the natural or necessary line, the remaining fruit will be certainly and perhaps greatly improved, and may very possibly more than make up in its aggregate weight for the excessive thinning.

Some vegetable plants are forced for use in winter by a process of simple self-exhaustion. Their strong roots being transferred in the fall to a cellar, or hot-bed frame, or heated pit, or green-house, yield a limited crop under the stimulus of the warmth thus furnished; this being obtained, the roots thus taxed are either thrown away or set out again in the spring to regain their ordinary strength. Sea-kale, Asparagus, Pieplant, Succory, etc., etc., are thus treated where it is deemed worth while.

The more common vegetables, as Lettuces, Radishes, and certain small matters for salads, require in their forced production in hot-bed frames but little if any more or different care, though longer continued, than is necessary for raising early hot-bed plants of various vegetables for setting out. See page 30.

Cucumbers and melons are often raised in unfavorable localities by a system of half forcing sometimes called "ridging." For this purpose a pit or trench of any desired length, about three feet wide and two feet deep, is dug at the close of spring, and filled with heating manure in the manner of making hot bed (see page 30), the manure being covered twelve or fifteen inches deep with surface earth well enriched with old garden compost and chopped half-rotted sod, adding sand or road-wash if the soil be heavy.

Potted plants, previously prepared in hot bed, are set out