REPORT OF THE SUPERINTENDENT OF GARDEN.
_______________________

   Sir: I have the honor to submit the following notes and remarks upon the progress and practical operations of the garden:
   At the risk of repetition, I would again allude to the limited area of the garden. It is highly necessary that the department should possess complete orchards of the various hardy fruits. At least one tree or plant of every variety should be kept, thus forming a living museum, which would be of great value for reference. As it is, only the small fruits can be accommodated, and, to test all the new varieties even of these, it is found necessary to eradicate those that proved to be comparatively worthless. This, although perhaps no great loss, does not fully serve the purpose of a national garden, which should preserve specimens of all, in order to assist in the identification of sorts, and also exhibit the progress made in their improvement.

GRAPES.

   Inquiry is frequently made as to the best mode of propagating the grape, the information sought, however, having reference more to the character of plant produced than to the mode of manipulation—whether the best plants are those produced from long cuttings, single eyes, or layers; and also to the relative merit of plants produced partially or altogether under glass, and those grown wholly in the open border. So far as the health of the plant is involved, as having an influence upon its future growth, there is no difference in any of the above-mentioned modes, provided it has ripened and thoroughly matured both wood and roots. Plants of the very best description have been produced from single eyes of young green shoots taken off in May, rooted, and kept in pots during summer. These have made growths from six to eight feet in length, thoroughly ripened to the tips of the shoots, and formed as fine plants as may be desired for permanent planting.
   To produce plants from such soft and succulent cuttings, it is absolutely essential that they be placed under glass and in a warm bed, technically bottom heat, and as soon as roots are formed the young plants are potted and kept growing freely under glass—but not in a close atmosphere—a position they may occupy until growth is complete; or, they can be planted out in the open ground by the end of July. Unless with new or rare varieties there is seldom any necessity for this mode of propagation, which requires considerable skill and care; but it is proper to state that as good plants can be procured by this as can be by any other mode, and, in respect to being exempt from old wood, it is superior to any other mode of propagation by cuttings. It is a system of multiplying all kinds of plants more universally adopted than any other, and answers quite as well with the grape as with any other plant.
   Where cuttings are plentiful, the most economical method of raising plants is by long cuttings in the open border. These should not be less than four inches in length, and need not be over six inches. Selecting a well pulverized soil, rather light or sandy, insert the cuttings in rows, pressing them down so that the bud rests on the surface; the soil should be in made firm around them, and if slightly covered with strawy manure (only a sprinkling—chaff will answer better if obtainable,) to prevent surface evaporation, a very large percentage will form fine plants without any further care than that necessary to keep down weeds and cultivate the surface.
   Ordinarily there is no hotter mode of propagating grapes than that known as by the single eye or bud. As indicated, these are made with one bud retained, and about one inch of wood below it. Plants from these have but very little old wood in their structure, and so approach as near as possible to a plant produced from seed, although, as far as this is concerned, the plant from a green wood cutting has decidedly the advantage. Single eye cuttings of old wood are generally placed under glass, and receive a slight bottom heat. This, however, is not indispensable, and they will do well on a green-house shelf. The great point in their management is to preserve sufficient moisture in the soil so as to prevent the sap in the cutting from exhaustion until the roots are formed. They may be planted out doors and succeed if caution is taken not to allow the surface to become dried; it is merely a question of evaporation. A slight bottom heat is useful to force the plant, but it should be applied very gently until indications of rooting appear. In climates where the growing season is comparatively short there is advantage gained in getting the plants well advanced before setting out.
   When roots are sufficiently advanced, the plants are placed singly in small pots, and planted in the open border as soon as the weather is favorable. As evidence of the strength and vigor of plants procured in this way, it may be noted that specimens have been grown in one summer, from single eyes set in spring, that have produced several pounds of fruit the following season.
   Wood intended for cuttings should be pruned off in November, cut in convenient lengths, and buried at once in the soil, covered at least nine inches. By doing so the sap is retained, and many failures in cuttings can be clearly traced to causes which will in this way be obviated.
   Layers of the young wood is another legitimate mode of propagating vines, and from old established plants a few shoots can be laid down during the early part of summer, form good rooted plants before winter, and that without materially injuring the fruit crop.
   As previously remarked, it matters but little to the future well-being of the plant as to which of the above modes have been employed in its production, provided it has properly matured its growth.
   There is one point in regard to roots which it may be well to mention. When the plants are grown in a deep, porous, rich soil, the roots ramify into numerous small fibres, which have been not inaptly described as "horse-tail like bunches." Plants having such appendages as roots are not in good condition for removal, inasmuch as these hair-like fibres are destitute of woody matter, and soon decay on exposure to the atmosphere. The possession of such roots is a very convincing proof that the plant has not completed for rather not matured) its growth, and its future progress will be feeble. Unfortunately there is too great a tendency to the production of such growth?, since most of the native grapes are more or less checked with mildew during the growing season, an influence which also extends to the roots. The best plants are those with the greatest amount of hard brown ripened tops, furnished with moderately strong, and what may be termed stout, wiry roots, and although these, to a novice, are not so enticing in appearance, yet they are the best adapted to furnish an abundance of fresh and vigorous spongioles, and, in consequence, vigorous plants.

PLANTING.

When the young vine is planted in its permanent location it should be pruned down to two buds, and this without reference to the manner of its propagation. Even the strongest layers should be so treated. One cane is sufficient to grow, but, to be prepared for possible accident, both buds should be allowed to start until the shoots are long enough to admit of tying to a stake, then the weakest may be removed or pinched back. During the summer the plant should be allowed to grow undisturbed, except tying up the shoots; the more foliage the more strength will the roots attain. The question is frequently asked, "At what ago should a vine be allowed to bear?" The only answer that can be given is, simply, when it is strong enough; and it should be cut down closely at the annual winter pruning until it sends up a cane of sufficient strength to bear fruit, which it will do, in ordinary culture, the second summer from planting.

PECULIARITIES OF VARIETIES.

   Of the Labrusca or Fox species, the most exempt from mildew are the Concord, Hartford Prolific, Ives's Seedling, Dracut Amber, and Northern Muscadine. All of the Cordifolia species are eminently hardy; mildew or rot rarely attacks them. The Clinton is a familiar example of this class, and the most reliable wine grapes will ultimately be produced from improved varieties of this section. The following is the average order of ripening of some of the earliest varieties: Adirondac, Hartford Prolific, Roger's Hybrid No. 3, Dracut Amber, Delaware, Concord, Logan, Creveling, Ives's Seedling, Roger's Hybrid No.4, Canby's August, Allen's Hybrid, &c. It may be remarked that the same varieties do not always ripen in the same rotation even on the same grounds and location.
   The best fox-grapes, or those having a strong musky flavor with great sweetness, are the Dracut Amber, Rachel, Northern Muscadine, and Perkins. These are all robust, and very hardy and productive; excellent for giving the genuine American flavor to wine, which will probably, in course of time, be regarded as a distinguishing characteristic of native wines. They are also good table grapes to those who admire this flavor, a taste for which exists to a larger extent than is generally supposed. Such strong wood-producing varieties as Clinton, Taylor, Alvey, Franklin, etc., do not require to be so closely pruned in the fall as those of less robust habit. They should be allowed considerable extent of trellis or support, so that they can extend the yearly growths to lengths of twelve, to sixteen feet, and pruned back but slightly; fruit will then be produced profusely; but, if closely cut in winter, a mass of wood growth only will be the result.
   The To Kalon is particularly subject to rot, so much so that it is not a profit able kind to plant.
   Of white grapes, the Cassidy and Anna are the most productive, Rebecca and Maxatawny best flavored. Allen's Hybrid and Clara are also good, but being seedlings from foreign varieties, are not always reliable. When they can be protected from mildew, satisfactory crops will be produced. Taylor is a poor bearer, unless on thin soils and with but little done to it in winter pruning. The Concord still maintains its supremacy (all things considered) as the best native grape for general cultivation; although subject (with all of its family) to rot, yet it always produces a fair crop, and being but little troubled with leaf mildew, the wood is well ripened, and consequently is least injured during winter. The Delaware is first-class, but not always reliable. The same may be noted of the Diana and Catawba, fruits of first quality when had in perfection. The Yeddo grape, from Japan, continues to prove unsatisfactory; very liable to mildew, and very late in maturing even when in health; fruit not of first quality when compared with the best native varieties.
   Of the Roger's Hybrids there are some very promising varieties. No. 3 is decidedly a good early grape. No. 4 large and fine in bunch and berry, and of medium quality in flavor. No. 1 is productive, later in ripening, but a white fruit of great promise. No. 15, large and very fine. No. 22, high flavored and ripening quite early. These vines are just about as subject to mildew as Catawba and Isabella, are very much better here than when grown where they originated—in this respect resembling the Concord and some other varieties. The Alvey proves to be a very sweet, tender skinned grape, and may be found of value for wine. It is not objectionable as a table grape. Ives's Seedling proves very hardy and reliable, but not equal to Concord as a table grape. Said to be valuable as a wine grape.

MILDEW.

   This is the great obstacle in the way of extended grape culture, and although the facts connected with its external appearance are very easily traced, the physiological condition of the plant when attacked, and the modus operandi of the progress of the disease, have given rise to much speculation, and some very strange fancies have been promulgated on the subject; but, unfortunately, none of them have proved to be of much advantage to the fruit grower. So far, the following points have been deduced from observation:
   1. That mildew on the leaves of the grape is mainly the result of atmospheric influences.
   2. The Peronospora, or mildew, that attacks the leaves on their under surface, is encouraged by the atmospherical conditions accompanying dull, cloudy weather, with occasional showers; or when heavy dews are deposited in positions where the rays of the sun cannot penetrate, or, at least, where the moisture cannot readily be evaporated.
   3. That, so far as is known, no peculiar constitution of soil, or mode of soil culture, has any influence in its prevention.
   4. That, so far as known, no mode of pruning or training, except so far as they agree with the fifth paragraph, has any effect in warding off the disease.    5. That shelter and protection by covered trellises, or masses of foliage, will greatly modify, if not entirely prevent injury from mildew.
   6. That varieties of grapes having downy foliage are much more liable to be attacked than those that are smooth or shining.
   7. That all grapes having downy foliage are not equally sensitive to the conditions favorable to the fungoid development, but where a pubescent foliage and a smooth foliage are growing side by side, the former, even of the most robust variety, may be attacked while the latter may be exempt from injury.
   8. That the appearance termed sun scald is simply the result of this mildew.
   9. That timely and repeated applications of sulphur, dusted on the foliage, will check the growth of fungi.
   Occasionally another form of mildew may be observed on the vine. This shows itself on the upper surface of the foliage, giving the leaves the appearance of having been dusted with flour; this belongs to the Erysiphe family of mildews, and, although very destructive, is not so fatal as the Peronospora. This floury looking substance can easily be removed by brushing the foliage: it is most frequently to be seen on foreign grapes, but may be observed on native varieties in seasons of extreme drought—dry weather seeming to favor the spread of this particular species. The young fruit and even young shoots are sometimes coated with this mildew. It retards growth and injures the plant at tacked, so that it is easily destroyed by slight frosts. Sulphur will both prevent and cure it.

CAUSES AFFECTING THE HARDINESS OF PLANTS.

   The occasional destruction of fruit trees and vines during winter is one of the many annoyances experienced by the cultivator; and it is all the more perplexing when it is found that a plant will sometimes be destroyed by a less degree of cold than it previously endured without the slightest injury. The amount of cold that plants are capable of resisting is a question of much interest, more especially when we reflect that the power of resistance is dependent upon circumstances which are, to a certain extent, under control.
   The necessity for protecting plants, even those of reputed hardiness, from the injurious effects of alternate freezing and thawing, is now admitted by the best cultivators, although it is not unusual to meet with those who pretend to place no value upon a plant that cannot "take care of itself;" as if it was not the province of man to assist nature in producing such results as he finds most profitable and useful. Those who "leave plants to nature," after placing them under artificial positions, only frame an excuse for ignorance or indolence.
   It has never been shown that frost is beneficial to plants; but it is a growing and well-grounded opinion, founded upon experience and observation, that many of the diseases of plants result from repeated injuries during severe frosts and extreme changes of temperature throughout the winter months. The exact manner in which plants are killed by cold has formed a subject of much speculation. The commonly received opinion is, that frost acts mechanically upon vegetable tissue by expanding their fluids and bursting the cells or vessels in which they are enclosed. This explanation, however, is not sufficient to account for all the phenomena attending the death of plants from cold. Doubtless many plants, especially those of a very succulent nature, may be destroyed from the disruption of tissue by the expansion of the sap in freezing. But it is also well known that the extraction of moisture by evaporation, when in contact with a continual cold, dry atmosphere, very frequently proves fatal. Thus it is that many plants which do not seem to be injured in the slightest by a degree of cold sufficient to freeze the sap, are destroyed by the keen, dry winds of spring, even when the thermometer, is above freezing; and hence it is that grapes, roses, raspberries, and other plants suffer more from March winds than they do from January frosts; and hence also the utility of protecting against this destructive evaporation. The effect of these drying winds is apparent in the shrivelled and dried appearance of the buds and bark; and although there is less likelihood of injury to thoroughly matured growths, yet it is in accordance both with theory and observation that plants whose juices are preserved by proper protection during winter will shoot forth more vigorously in spring, are more fruitful, and arrive earlier at maturity than those not sheltered from climatic extremes.
   It cannot be too vividly impressed upon the mind of the cultivator that the ripening of the seasonal growth is the greatest desideratum. How much of the disappointment in fruit culture arises from excessive stimulation of shoots that never become mature, it would be no easy task to determine. We are convinced that the time is rapidly approaching when planting fruit trees and vines in highly enriched soil, and treating them with heavy dressings of nitrogenous manures, will be looked upon as conclusive evidence of unskilled culture. Not that all stimulation is unnecessary, but that the production of mere wood-growth and the production of fruit are distinct, and may be carried so far as to become antagonistic processes, and must be recognized before the highest excellence in fruit culture can be attained.
   On the best means of prevention from the evil effects of freezing plants, the following remarks of Lindley are to the point : " The mechanical action of frost may, however, undoubtedly be guarded against to a great extent. It is well known that the same plant growing in a dry climate, or in a dry soil, or in a situation thoroughly drained from water during winter, will resist much more cold than if cultivated in a damp climate, or in wet soil, or in a place affected by water in winter. Whatever tends to render tissue moist, will increase its power of conducting heat, and consequently augment the susceptibility of plants to the influence of frost; and whatever tends to diminish their humidity, will also diminish their conducting power, and with it their susceptibility. This is an invariable law, and must consequently be regarded as a fundamental principle in horticulture, upon attention to which all success in the adaptation of plants to a climate less warm than their own will essentially depend. The destructive effects of frosts upon the succulent parts of plants may thus be accounted for independently of the mechanical expansion of their parts; indeed, it is chiefly to that circumstance that the evil effects of cold in spring may be ascribed, for it has been found that trees contain nearly eight per cent, more of aqueous parts in March than at the end of January, and all experience shows that the cultivation of plants in situations where they are liable to be stimulated into growth and, consequently, to be filled with fluid by the warmth and brightness of a mild protracted autumn, exposes them to the same bad consequences as growing them in damp places, or where their wood is not ripened; that is to say, exhausted of superfluous moisture, and strengthened by the deposition of solid matter resulting from such exhaustion."
   The ripening process consists in the slow but gradual and complete removal of watery matter, and the conversion of fluid organizable materials into the more solid substances which are necessary to form woody fibre; and its effects are not only seen in the power conferred of resisting cold, but also in providing an abundance of the secretions necessary to sustain the growth of the following spring, and produce the flower-buds upon which future hopes depend; for it is well Known that flower-buds will not be produced unless the elements of growth have been maintained in due relative proportions.
   We can thus partly see how far it is in our power to assist nature in supplying the requisites for perfect maturation of growth. The fruit grower will be careful to avoid planting in wet or highly enriched soil that would tend to en courage prolonged growth in the fall; he will see that his strawberry plants are not neglected during summer after the crop is gathered; that weeds are prevented from gaining a foothold; that the plants are thinned and fully exposed to sun and air, in order to perfect flower-buds for the following spring; that his raspberry plants have been divested of the old bearing wood, the young shoots thinned and disposed at proper distances so as to allow them a free enjoyment of light; that his grapevines have an abundance of healthy foliage, so as to ripen the young wood for his future crop; and that his peach trees are not suddenly denuded of their foliage, while it is as green and fresh as in the month of June.
   When a fundamental principle is once determined and understood, operative details are suggested, and from them the best practical mode of application is readily deduced; for instance, many of the most beautiful evergreen ornamental trees, such as the Asiatic conifers as well as those from the western coast of this continent, cryptomerias and deodars, sequoias and taxodiums, have, in our moist fall growing weather, a tendency to make a luxuriant growth which never ripens, and, as a natural consequence, it is destroyed by winter cold. Now, if these growths are checked in September by judicious root-pruning, the wood will mature, shoots become hard and woody, and, instead of being unripe and filled with watery fluid, be solid and firm, and fully prepared to stand the extremes of our wintry climate. The whole subject of the acclimation of plants is based upon maturity of growth.

ROTATION OF CROPS
Among the essentials requisite to maintain a high degree of success in cultivation, a proper system of rotative cropping occupies a prominent place. The advantages of rotation in farm crops are well known; yet, in the garden, the practice is very common to grow the same kind of crops for years in the same spot of ground. It is, perhaps, within the bounds of possibility to pursue this course successfully, but to do so will require an annual return to the soil, in some form, of the several ingredients extracted by the plants. Our knowledge of the application of science will not warrant much faith in this direction, even if chemists were decided as to exact respective amounts of the ingredients used by various crops. But allowing it to be practically attainable, and looking at it in the light of mere economy, a change of crop is every way desirable; since by proper care two dissimilar crops may be produced on the same ground in the same season; and, further, the operations necessary for the culture of one kind of crop are of a nature to form a good preparation for the succeeding one.
   Physiologists do not altogether coincide in their opinions with regard to the principles upon which the beneficial results attending systematic change of crops are based. Some support what may be termed the repletion or excretory theory, which proceeds on the supposition that the roots of all plants during their growth give out certain substances peculiar to themselves, which, in time, impregnate the soil to such an extent as to render it unfit for the growth of that particular plant, but has no deleterious effect upon the growth of a different family of plants, if, indeed, they>are not rather to be considered as capable of promoting growth and acting as stimulants to such.
   It is a well ascertained fact that certain if not all plants do impart to the soil, through their roots, a portion of their juices. The soil surrounding the roots of the oak tree has been found impregnated with tannin. The roots of the spurge laurel impart an acid, resinous matter. The poppy exudes a substance analogous to opium; the root of any plant growing in water will soon render it turbid, but the quantity of such matters hitherto detected has not been considered sufficiently important to account for the remarkable beneficial results which "have followed a rotative system of cropping.
   The above theory has been supported by very high authority, but it seems to be giving way to the following, viz : that although plants are made up of the fame primary elements, yet different species require them in widely varying proportions, so that each plant has a characteristic formation peculiar to itself. It therefore follows, that if there is a lack in the supply of these peculiar ingredients of plant food, the plant will not be maintained in healthy growth. From this it appears that the reason why a crop, if constantly grown upon the same spot of ground, shows a yearly loss in productiveness, docs not arise from a repletion of any substance, but rather from exhaustion. In a practical view, it is evident, from either of the above theories, that a change of crop is requisite to successful cultivation.
   In cultivating garden vegetables great facilities are presented for a frequent change of crop, and there is, also, a wide field for experiment in order to ascertain the kinds best suited to succeed one another in a regular system. For instance, it has been asserted that melons will produce best when grown on soil previously occupied by tomatoes. In general, long, tuberous, rooting plants, as carrots, beets, parsnips, &c, should be followed by those that root near the surface; plants that are cultivated for their seeds should be followed by those grown for their foliage. The seeds of all plants contain a larger amount of the mineral ingredients than their leaves, so that plants grown for their seeds will exhaust the inorganic matter of the soil to a greater degree than will be effected by plants grown only for the use of their leaves.
   In the arrangement of crops in the field or garden, there are two methods that may be adopted, either of which will provide for rotation. In the first place a spot of ground is occupied wholly by one crop, and when that is removed its place is immediately occupied by another; or two or more crops are so planted on the same piece of ground that the one will be ready for removal before it interferes with the growth of the other. The first method may be illustrated by planting with early peas or potatoes, which will be removed in time for planting cabbages or celery, or sowing beets, turnips, or spinach. Early crops of carrots and beets will be removed in time for a planting of late dwarf beans. Many modifications will be suggested in practice. Perhaps the most economical method, especially where ground is limited in quantity, is to grow several crops at the same time on the same piece. For instance, peas may be sown in March, in rows, six feet apart; in May a row of melons may be planted between the peas, the shade afforded by the peas will benefit the young melon plants, or, between the peas a row of dwarf beans may be planted, and when the peas are removed their place may be occupied by cabbages, and the beans be succeeded by a crop of turnips. It does not seem necessary to multiply examples, as those who are inclined, and will exercise due foresight, will suggest many expedients.
   Much variety can be produced in even a small garden by this method, and it affords great facilities for sheltering young and tender crops by those of more matured or robust growth. It may, however, be remarked, that although most plants are benefited by a little shade and shelter when young and delicate, it is highly injurious when long continued.

FOREIGN GRAPES IN GLASS STRUCTURES.

   The simplicity and certainty with which the foreign grape can be produced in glazed houses is not generally known. Many amateurs, whose success with other fruits is quite satisfactory, feel doubtful of their ability to manage the exotic grapery.
   To those whose only acquaintance with the subject is derived from perusing publications on the growth of this fruit, the supposition of inability is pardonable; for there is certainly much to appal the beginner, in perusing the various ideas of soil and border making, the conflicting opinions relative to watering, and the multitudinous, fussy details of management, which he will find in print. So much has been written of late years on this subject, that it would not now be referred to were it not with a hope that information might be imparted that would tend to dispel the idea of difficulty or mystery, in connexion with the culture of this, without exception, most economical of fruit productions. It is well known that, in favorable locations, the Chasselas, Black Hamburg, and many other of the varieties of the foreign grape will occasionally produce perfectly ripened fruit with no further care than that usually given to the Isabellas, or any other native variety. But although the result may occasionally be reached, it is well known that all attempts to cultivate the foreign grape in the open air, east of the Rocky mountains, have, sooner or later, proved abortive.
   That these failures are attributable either to a deficiency of sunlight or to a deficiency of summer heat are questions easily answered; for we find that in the Climate of Britain, where the dull, sunless days are more abundant, and the summer heat of less intensity and of shorter duration than with us, the Hamburg and other exotic grapes ripen yearly, trained on outside walls and trellises, and this in a climate where the heat is not sufficient to mature Indian corn, tomatoes, or even peaches, in common field culture as with us. Neither can it be supposed that our own summers are too hot, or our winters too cold, as it is well known that there is scarcely any plant that will withstand extremes of summer heat and winter cold so well as the grape, provided it maintains good health. But unfortunately, there are climatic conditions .here during which the grape is rendered subject to the attack of fungoids, by which its growth is checked, the wood prevented from maturing, and a general debility engendered which enfeebles the plant to a degree that, sooner or later, ends in its total destruction.
   This tendency to mildew is, then, the only obstacle in the way of successful open air culture, in this section, of the best wine and table grapes of Europe; and is the only reason why glass structures have to be employed in their culture, where an artificial temperature, more in accordance with their requirements, may be maintained. The tendency to mildew in the foreign grape, having been found so great a barrier to its extended culture in the open air, recourse was had to glass houses where protection could be afforded and means adopted for the exclusion of this malady; but in many cases, even here, success has not been equal to expectations. The mistaken eagerness of many to keep the plants in an artificial instead of a natural condition, has led to frequent failures. It appears very obvious that a plant which occasionally succeeds in the absence of any particular protection, would be enabled to do so uniformly by a very slight additional care, provided that this additional care was bestowed in the proper direction; and that such is the case has been proved beyond a doubt.
   Having on another page of this report treated more particularly on mildew and its origin, it may suffice to remark here, that it is altogether dependent upon the amount of atmospheric moisture, and proper ventilation; and without proper attention to these points, mildew is just as likely to destroy the plants under glass, as it would be those in the open air. Keeping in view that these remarks are intended to refer to the general routine management of what is now more definitely known by the term cold grapery, we will briefly allude to what is considered the main points of treatment.    The principal points, then, are a low night temperature, exclusive top ventilation, and tht constant presence of moisture available for evaporation. The baneful effect of a high temperature in plant-houses has been shown in previous reports. It has been proved repeatedly that low or bottom ventilation in a grapery is conducive to mildew, and aridity must be prevented by the presence of moisture.
   It would require considerable space to enter fully into the elucidation of all the principles involved; it will, therefore, be considered sufficient for the present to briefly trace the course of practice deduced from many years' extended observation and experience in the growth of the foreign grape.
   As soon as spring growth commences, attention is at once directed to the night temperature, so that it will fall at, least 20 degrees below the average heat in the house during the day. In dull, cloudy weather, of course, this difference be tween day and night may not be so great, and if the nights are frosty, it will be necessary to close the house; but in the absence of actual external freezing, the ventilators, should not be wholly closed, even during night. When all danger from night frosts is passed—which will vary, according to locality, from the middle of May to the middle of June—the ventilators may be left open day and night. During dull cool weather it may be necessary to partially close the ventilation both day and night; but as a general rule, the same amount is used day and night. We have seen graperies where the ventilators were never disturbed from the period of blossoming until the ripening of the fruit. No constant anxiety is, therefore, felt about sheltering or opening sashes, and the liability to create sudden changes of temperature, that frequent alterations of the ventilators are sure to produce, is prevented. The temperature of the house will, therefore, participate in the general changes of external atmosphere, and though warm during sunlight, will be cool during darkness. During the warmest portion of the summer, the day temperature may vary from 90 to 110 degrees by day, to 65 to 80 degrees during the night. This lowering of temperature during darkness insures a hardihood of growth that enables the plants to endure any unfavorable change that may occur, without sustaining the least injury.
   As air is heated, its capacity for abstracting and containing moisture increases, and unless the moisture is supplied from other sources, it will be drawn from the plants. To supply this evaporation, the soil should be kept damp on the surface. Once a day at least, in bright weather, the soil will require to be sprinkled. It is a good rule never to allow the surface soil to be entirely dry until the fruit is coloring to ripen; but it is important to know that, unless in connexion with constant night ventilation, this treatment may prove injurious.
   So far as the management of the atmosphere is concerned, this is all the care required, and a crop of grapes is thus as easily grown as a crop of potatoes, only with more certainty, because more under our control.
   With regard to soil, pruning, &c., we will at present only remark, that soil capable of growing good cabbages will grow good grapes, and the strongest yearly growths give the best fruit.

MULCHING.

   This is an auxiliary operation in cultivation, that would be more generally practiced if its beneficial effects were better understood. ' The objects to be attained by mulching are twofold, viz : to preserve a uniform degree of moisture in the soil during summer, and protect the roots of plants from severe frosts during winter. These conditions are obviously important to vegetation, and they can be very efficiently secured by covering the surface with a stratum of porous materials, such as tan bark, charcoal dust, leaves, or strawy manure, which will prevent the surface soil from becoming compact or hard, and, at the same time, assist in maintaining a uniformity in its mechanical texture favorable to the retention of moisture. Air is the best non-conductor, and bodies are represented as good or bad conductors, just as they are solid or porous. Iron is a better conductor than wood, granite stone a better conductor than brick, hard pressed soil is a better conductor than soil that is loose and porous. A hard trodden path is warmer in summer and colder in winter, than the cultivated ground alongside of it. When the soil particles are in pressed contact, the condition is favorable to rapid conduction; summer winds passing over such a surface, carry off the moisture which the heat evaporates; the surface is speedily parched dry, and vegetation languishes.
   When the surface is covered with a mulch of such porous materials as those enumerated, it in effect secures a stratum of air in repose between the soil and the causes of radiation and evaporation. In the case of recently planted trees, the preservation of a uniform degree of moisture in the soil surrounding their roots, is a great point towards their successful growth; and, other things being equal, they will languish or flourish in proportion as this condition of uniform moisture is secured.
   Although mulching is really a very simple operation, yet serious losses have occurred from its misapplication. We have seen trees destroyed from too heavy mulchings of grass, manure, and tan bark. Before applying the mulch to a recently planted tree, if in spring, shape the soil around it in basin-form, extending the rim beyond the extremities of the roots; by this configuration of sur face, rains will be retained and, if required, artificial waterings can be applied to best advantage. With regard to fall planting, the process should be reversed and a slight mound formed towards the stem of the plant, so as to throw off the heavy rains of winter. Of course such mound should be removed before the following summer.
   As already remarked, the principal use of winter mulching is to prevent frosts from reaching, the roots. The best material for this purpose is charcoal dust Where manure is used, it should not be thrown close up to the stem of the plant, otherwise it might prove a harbor for ground mice, which in rough ground, or under a coarse covering, are sometimes very destructive, by eating the bark of young trees. When they are troublesome, the precaution should be taken to trample firmly over the roots and around the stem after heavy snows, and keep the surface clear and compact.
   In order to be effectual, it is not necessary that summer mulchings should be heavy. When tan or charcoal dust is used, a layer of two inches in depth will be quite sufficient. Grass cut from lawns is very suitable, but a mere sprinkling only should be applied at a time. Thick coatings promote fungoid growths, which frequently destroy trees. Fruit or ornamental trees that have been transplanted, will rarely be much benefited by mulching after the first year's growth. The advantages of mulching to growing vegetables are equally important. Cabbages, potatoes, peas, onions, and other crops, will thus be enabled to maintain growth during the driest weather, This covering is not intended to supersede stirring the soil, but when plants become so far advanced in growth as to be beyond the hoe and plough, mulching may be applied, and those who give it a fair trial on their crops in a dry season, will not require further promptings to repeat the practice.

HEATING GLASS STRUCTURES.

   An efficient system of heating green-houses is always a matter of much interest in their construction and adoption; the expenses attending the fitting up of a heater and the subsequent cost of fuel have always been great obstacles, and have been the means of preventing many persons from building, more particularly since it has been an opinion somewhat prevalent that a boiler and pipes for the purpose of heating and circulating water is indispensable for the proper diffusion of heat. There is no doubt that water is the best conductor of heat, and, where extensive houses are to be warmed the superiority of water in this respect, together with other advantages connected with its application, such as neatness, cleanliness, &c, will always point out that mode as being the most desirable. Looking at it as a matter of mere economy, we can at once decide that the cheapest mode of heating green-houses is by means of well-built and properly constructed flues. At present prices of material and labor it is probable that for a house, say sixty feet long by twenty wide, it would cost ten times more to erect a boiler with sufficient piping than would be required to build a furnace and flue. But the economical advantages of the flue are not all absorbed in its first cost. Even with the best form of boiler there is great waste of heat which may be economized in a good flue. To prove the above assertions would take more space than we purpose, neither is it indispensably necessary at present; the object in view is to show that there is much fallacy extant concerning the great superiority and economy of heating by hot water, and to attempt to describe some points in the construction of an efficient furnace and flue.
   The furnace should not be less than two and a half feet in length; one foot wide, and sixteen inches in height; the sides should be lined with good fire brick placed on edge, backed by four inches common brick. Very little mortar should be used, and that quite thin; indeed, they are frequently laid without mortar—that is, the fire-brick casing. The arch or covering is formed by projecting fire-brick a few inches over the sides, so that the opening left can be covered by one length of the same kind of brick, the whole covered and made level on top by two or three courses of common brick. This is quite as strong for the purpose intended as a regularly built arch, and saves material as well as labor in constructing. On each side of the furnace a space of four inches in width is left to cut off the head from, communicating with and being absorbed by the surrounding building or earth. This chamber is continued the whole length of the furnace, and also a few feet on the flue opening into the house. As soon as the sides of the furnace become heated the cold air will rush in, collect the heat radiating from the exterior of the furnace and convey it into the house, thus completely preventing disruption by expansion, a frequent occurrence in furnaces of great apparent solidity. In order to assist in the combustion of the gases of the fuel, and also increase the draft and propulsion of the heat through the flue, an opening at least six inches square should commence at the end of the ash-pit, continuing under and entering into the bottom of the flue two feet from the back of the furnace.
   The greatest defect of the smoke flue is its unequal distribution of heat. In this important particular hot water pipes have a great superiority. The whole extent of their surface being heated to a nearly uniform degree, the heat is given off at a comparatively low temperature; whereas, near the furnace the flue is heated to excess, while the greatest portion of it imparts little or no warmth to the atmosphere.
   This is the flue as ordinarily constructed with brick set on edge; it has been found, however, that by adopting the principle of diminishing the thickness of the material of which it is constructed, as it recedes from the furnace, a flue can be made so as to radiate heat over its entire surface at nearly the same temperature. As an example, supposing 100 feet of flue were required in a house, then the first ten feet from the furnace would be formed of brick-work four inches in thickness, covered on top with a double thickness of brick; then the following thirty feet would be made of bricks on edge, covered by a single brick; then finish the length with terra cotta piping of eight inches diameter, which is usually about three-quarters of an inch in thickness. A flue so built will absorb heat very regularly over its surface, and so far will approach a hot- water apparatus in efficiency, at a greater economy of fuel and at a cost easily reached.
   It is well to have the flue as roomy as possible, especially near the furnace. When common brick are used for covering, the width inside cannot be more than seven inches; if its height is made of three bricks on edge, its dimensions will be about twelve inches by seven inches inside. The less mortar used in the joints, the longer will it stand, and all plastering of the flue, either inside or out, is very objectionable. It is also well to keep in view that hard-burned bricks will transmit heat more rapidly than those that are soft and porous. In all cases, where practicable, the flue should rise one foot in twenty from the furnace. If one foot in ten feet can be gained, so much the better.

MECHANICAL PREPARATION OF SOIL.

   The physical or mechanical condition of the soil, its relation to air and water, has not received that attention from agricultural chemists which its importance demands. They have devoted their investigations almost solely to its chemical constituents, seeming to lose sight of the fact that the permeability of the soil to atmospheric influences is of more importance than the most approved manures. If the money that has been expended upon artificial manures during the last twenty years had been devoted to drainage, sub-soiling and trenching, the products of the country would have been vastly increased.
   The soil performs various offices towards growth of plants. It serves as a basis in which they may fix their roots and sustain themselves in position; it also supplies inorganic food during all periods of their growth, and may be looked upon as a laboratory in which many chemic changes are taking place, preparing the various kinds of food which it is destined to yield to the growing plant. Analyses have shown that in most soils the presence of all the constituents of the ashes of plants may be detected, though in variable proportions. But the mere presence of certain substances in soils does not insure productiveness, for it has been shown that crops have failed even in soils possessing all the mineral ingredients required, because, although present, they were not in a sufficiently soluble state to be available. Thus in wet, clayey soils, although containing enough of plant food, the water prevents free access to the decomposing influence of the atmosphere, and crops perish; not because of a deficiency of raw material, but on account of the processes for its preparation being arrested.
   This leads us to the foundation of all improvements of such soils, viz., draining. It is a remark frequently made by those having no experience, that draining must be worse than useless in a climate where summer droughts are among the greatest calamities against which the cultivator has to contend. All who have witnessed the effects of draining need not be told, that even in soils not particularly retentive, draining, in connexion with deep culture, will secure a more ample and lasting supply of moisture in dry weather, and maintain a growing vegetation during the most severe droughts. Draining increases the capability of the soil for absorbing moisture; all soils have their certain absorbing properties; like a sponge, they absorb until their pores are filled, and only the superfluous water that cannot be taken up passes through the drains.
   Draining is only the first step towards improvement. The soil must be deeply loosened and pulverized, either by subsoiling or trenching. Either process will be beneficial, and circumstances will decide as to which is to be adopted. Trenching involves a thorough reversion of the soil, of more or less depth, according to its nature and the purposes for which it is to be used. Subsoiling is merely a loosening or stirring up of the immediate subsoil, without reversing its position. When the ground is intended for a permanent crop, such as fruit trees, grapevines, &c, trenching may be adopted. The top surface of good soil will then be placed where the roots will be immediately benefited by it, and the crude subsoil brought to the surface, where it can be enriched by the aid of manures and the ameliorating processes of cultivation.
   On the other hand, if the ground is to be immediately cropped with small seeds, as in some portions of a vegetable garden, a finely pulverized surface is necessary, and few subsoils can be made available, or be reduced to that condition while in their crude state. Subsoiling will, in such cases, be most advisable, and trenching can be executed as crops will admit of the. operation.
   The first process, then, towards securing a profitable depth of soil is draining; next breaking into the subsoil, taking into consideration, whether, in view of the crops to be cultivated, it will be most immediately profitable (of ultimate profit there is no uncertainty) to trench it at once, or merely break up and loosen the subsoil, admitting water and other fertilizing agencies to penetrate, and by a gradual trenching improve to the required depth. When all this has been satisfactorily accomplished, manures can be applied to the greatest advantage, and failures from droughts almost entirely obviated.
WILLIAM SAUNDERS.

   Hon. Isaac Newton.