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From the Spectator.
derive insight into the deeper mysteries of nature from the disjointed talk of sleepwalkers, is about as reasonable as to anticipate revelations NEXT after Nonintrusionism and Repeal, Mes- from the jabbering of maniacs. The exhibition merism numbers the most fervid votaries. of their antics to crowds of incompetent and exIn Paris, we learn from a correspondent of the cited spectators, is only calculated to spread the Morning Herald, there are professional "som- contagion. The habit of taking part in such nambules," who make a livelihood by exhibiting displays inevitably tends to reduce the experithemselves under the influence of the mesmeric menters to the level of itinerant lecturers on inmanipulations, at private parties. They are of toxicating gases, the "great Wizard of the all ranks, in order that the bienséances may not | North," and others whose sole aim is to produce be violated by having a grisette magnetized on startling effects. This is not the kind of pubthe sofa of a dutchess. Though not to the same licity that affords security against deception. extent, something of the same kind is practised All jugglers, from the high-priest of a false reliin London. The mesmerizer is generally at-gion down to the manipulator with the pea and tended on public occasions by one unchanging thimble, can tell that crowds are more easily demesmerizee; and some of these cataleptic pin-luded than single persons. cushions are suspected to have been "rather hard up" before they took to this line of business. From a provincial paper we learn that Dr. Elliotson has had, or is to have, the honor of exhibiting before a party of the Queen Dowager's Maids of Honor, who have "openly and unhesitatingly" avowed themselves converts to mesmerism-her Majesty's Maids of Honor being, of course, high authorities on a physiological question.
As far as the mere physical symptoms go, enough has been confidently affirmed to entitle them to the serious investigation of physiologists. As to what is told of patients in the stage of "clairvoyance," and their intuitive powers of knowledge, Dr. Elliotson is, it seems, of opinion, that in this condition such an irresistible taste for lying is developed in the patient, as renders it necessary to receive all his (or her) statements with considerable skepticism. With regard to the mesmeric phenomena, as with regard to every subject of observation, it is advisable to learn the elements of a science before venturing upon its most abstruse and complicated problems. It may also be advisable to keep in view a weighty observation of the late Sir Charles Bell-that in studying the living subject, observation is far more to be relied upon than experiment. Mesmerism is merely an arti ficial method of producing the phenomena of somnambulism, which are in some developed by a natural process. The physiologist who patiently and attentively watches the phases of the spontaneous disease, may be certain that he sees Nature working: he who by artificial means creates it, knows not what allowance he ought to make for forcible derangement of function.
But if fashionable mesmerism has not attained the éclat in this capital which marks its progress in Paris, popular mesmerism in the provinces has reached a degree of intense excitement unparalleled in France. Mesmeric "classes for the million" are being organized à la Hullah. In Glasgow, seven-and-thirty mesmeric patients "all in a row" have been exhibited at once, in the largest hall of the city, to a crowded audience. Young ladies have been kept sitting in the cataleptic trance "an hour by Shewsbury clock," with their legs stuck straight out before them, and in other comical attitudes; young gentlemen in a state of somnambulism have been attracted by a flower, backwards and for wards, across a stage, as a swan of white wax with a needle in its belly is drawn by a magnet across a basin of water; and the wondering The mesmeric phenomena, it is said with spectators have applauded all the while, with some plausibility, threw light upon much that an earnestness and sincerity equal to that with was inexplicable in old authenticated stories of which the "galleries" in the General Assembly priestly oracles, demoniacal possession, witchcheered the evacuation of the hall by the seced-craft, &c. If the remark is correct, it only shows ing ministers and elders. that mesmerism has been long enough an engine of quacks: not much will be gained by taking it out of the hands of the jugglers of the idolatrous altar and sorcerer's cave, to place it in the hands of the jugglers of the theatre and conjuror's booth. It is too sharp an edge-tool to be made a plaything of. That the magnetic sleep has been made the means of alleviating the pain of disease and facilitating the transition from sickness to health, may be conceded; and yet, even in the case of the regular physician,
The follies of fashion and popular excitement cannot convert a truth they may run after for a time into a falsehood; but they are absurd and mischievous in themselves, and they never promoted a discovery. The exclusive mesmerizers of the salons and the gaping crowds of public exhibitions are alike in search of excitement, and nothing more. These reunions are something like the melodramatic displays of poor Edward Irving, before daylight of a cold frosty morning, by one glimmering taper placed on the pavement of the chapel-for that too, and the gift of the unknown tongues, were phases of mesmerism; and their consequences can at best be but the same-the unsettling the reason of some of the more excitable among those who take part in them. The mesmeric phenomena (admitting their reality) are the result of disease -the result of a derangement of the normal state of the human constitution. To hope to
"Scarce we praise his venturous part
Who tampers with such dangerous art." But when this inversion or perversion of the physical functions is practised for the mere gratification of idle curiosity, we ought to apprize the unwary, that this is culpable trifling with an agent which has often irremediably shattered the constitution of individuals and distressed the peace of families.
SMITH'S PRODUCTIVE FARMING.
From Tait's Magazine.
merely to the application of correct principles
of results, and a ready adoption of really useful
THIS well-digested Treatise comes out exactly as a work of the sort is urgently required for the instruction, and also for the comfort and encouragement of the farmer. With the vague undefined terror of the utter ruin which Corn-law abolition is to produce hanging over him, and while suffering under the Tariff panic, together with the real evils of exorbitant rents and fluctuating markets, the British Farmer now more than ever requires to be told how he may retrieve his affairs and improve his future condition. This is to be done simply by rendering his acres more productive, by means of improved principles of husbandry, originating in the discoveries of science and philosophically applied to the cultivation of the soil. In the Introductory Observations to this Treatise, Mr. Smith contrasts the rapid, the indeed marvellous progress of all sorts of manufactures within the last half century, from the discoveries of chemical and mechanical science, with the stagnant condition of agriculture,-with, in other words, the manufacture of corn and of the other kinds of food. Within that period, the steam-engine and the jenny have, in manufactures, taken the place of manual and There is, at the present distressing crisis, animal labor, of the primitive hand-loom cheering and consolation for all classes of and the spinning-wheel, and with an in- society in the spirit of these remarks. The creased power of production which it is treatise which they introduce is, strictly not easy to calculate; while the sons of speaking, a judicious compilation. It is, the soil, who ought to have made some perhaps, its distinguishing merit that it is effort to keep pace with the march of im- so, and that from its pages the practical provement, still plod on through winter's farmer may obtain such a degree of insight cold and summer's heat, reaping not much into those general principles upon which more than the same quantity of produce all successful cultivation rests, as will which their forefathers did five hundred years ago. And yet this writer contends that the limits of the earth's fertility are no more to be permanently fixed than the powers of manufacturing productiveness. Both are alike under the dominion of mind. Nor will any one deny that the ultimate limits of the earth's fertility are only, from the still imperfect lights of science, but beginning to be guessed at. Mr. Smith remarks,
awaken his mind to the necessity of farther inquiry, besides informing it. The Lectures of Sir Humphrey Davy on the Chemistry of Agriculture, and those of Dr. Mason Good, the writings of Johnston the agriculturist, and, above all, the important views more recently unfolded by Professor Liebig, are presented to the farmer in a condensed form, and stripped of those technicalities in which men of science sometimes invest their discoveries, as if to veil them from the uninitiated, or the men of plain sense and plain education. A more useful work could not therefore be given to the practical farmer, than this Productive Farming; or a Familiar Digest of brief and lucid exposition of the first printhe Recent Discoveries of Liebig, Davy, and other ciples of his art, and of their results in incelebrated writers on Vegetable Chemistry; show-creased production. The treatise is dividing how the results of English Tillage might be ed into thirteen chapters, the earlier ones greatly Augmented. By Joseph A. Smith. Edinbargh: Tait. London: Simpkin, Marshall, & Co. being more purely scientific, while the
Half a century sufficed to Europeans, not only to equal, but to surpass the Chinese in the arts and manufactures; and this was owing
latter chapters are strictly practical. To it does not contain them: the plant may, indeed, give an idea of the nature and objects of under such circumstances, become an herb, but the work, we shall, at random, cite a few will bear no seeds. We say phosphate of magdetached sentences from its practical de-nesia is necessary; the small quantities of the phosphates found in peas and beans is the cause of their comparatively small value as articles of nourishment, since they surpass all other vegetable food in the quantity of nitrogen they contain. But as the component parts of bone, namely, phosphate of lime and magnesia, are absent in beans and peas, they satisfy appetite without increasing the strength.
Let us premise that Mr. Smith patronizes no systematic fallows. He shows how the necessity for them may, in all cases, be
The exhaustion of alkalies in a soil by successive crops is the true reason why practical farmers suppose themselves compelled to suffer land to lie fallow. It is the greatest possible mistake to think that the temporary diminution of fertility in a field is chiefly owing to the loss of the decaying vegetable matter it previously contained: it is principally the consequence of the exhaustion of potash and soda, which are restored by the slow process of the more complete disintegration of the materials of the soil. It is evident that the careful tilling of fallow land must accelerate and increase this further breaking up of its mineral ingredients. Nor is this repose of the soil always necessary. A field, which has become unfitted for a certain kind of produce, may not, on that account, be unsuitable for another; and upon this observation a system of agriculture has been gradually formed, the principal object of which is to obtain the greatest possible produce in a succession of years, with the least outlay for manure. Because plants require for their growth different constituents of soil, changing the crop from year to year will maintain the fertility of that soil (provided it be done with judgment) quite as well as leaving it at rest or fallow. In this we but imitate nature. The oak, after thriving for long generations on a particular spot, gradually sickens; its entire race dies out; other trees and shrubs succeed it, till, at length, the surface becomes so charged with an excess of dead vegetable matter, that the forest becomes a peat moss, or a surface upon which no large tree will grow. Generally long before this can occur, the operation of natural causes has gradually removed from the soil substances essential to the growth of oak, leaving others favorable and necessary to the growth of beech or pine. So, in practical farming, one crop in artificial rotation with others, extracts from the soil a certain quantity of necessary inorganic matters; a second carries off, in preference, those which the former had left, and neither could nor would take up.
Experience proves that wheat should not be attempted to be raised after wheat on the same soil; for, like tobacco, it exhausts the soil. But, if "humus," decaying vegetable matter, gives it the power of producing corn, how happens it that, in soils formed in large proportion of mouldered wood, the corn-stalk attains no strength, and droops permanently? The cause is this: the strength of the stalk is due to silicate of potash, and the corn requires phosphate of magnesia; neither of which substances a soil of decaying vegetable matter can afford, since
Again, how does it happen that wheat does not flourish on a sandy soil, and that a limestone soil is also unsuitable, unless mixed with a considerable quantity of clay? Evidently because these soils do not contain potash and soda, (always found in clay;) the growth of wheat being arrested by this circumstance, even should all other requisite substances be presented in abundance. It is because they are mutually prejudicial by appropriating the alkalies of the soil, that wormwood will not thrive where wheat has grown, nor wheat where wormwood has been.
One hundred parts of wheat straw yield 15 of ashes; the same quantity of barley straw, 8; of oat straw, only 4: the ashes of the three are, chemically, of the same composition. Upon the same field which will yield only one harvest of wheat, two successive crops of barley may be raised, and three of oats. We have, in these facts, a clear proof of what is abstracted from the soil, and, consequently, what plants require for their growth, a key to the rational mode of supplying the deficiency.
Potash is not the only substance requisite for the existence of most plants; indeed it may be replaced, in some cases, by soda, magnesia, or lime; but other substances are required also.
We cannot go farther on this topic. Let us take another and more limited case of agricultural economy, guided by science.
The offensive carbonate of ammonia in close stables is very injurious to the eyes and lungs of horses, as the army veterinary surgeons are well able to testify. They adapt measures to carry it off by ventilation and cleanliness. If the floors of stables or cow-sheds were strewed with common gypsum, they would lose all their offensive and injurious smell, and none of the ammonia which forms could be lost, but would be retained in a condition serviceable as manure. This composition, swept from the stable floor, nearly constitutes what is sold under the denomination of urate. Manufacturers of this material state, that three or four hundred-weight of urate form sufficient manure for an acre: a far more promising adventure for a practical farmer will be to go to some expense in saving his own liquid manure, and, after mixing it with burnt gypsum, to lay it abundantly upon his corn-lands. For, in this way, he may use as much gypsum as will absorb the whole of the urine.
We have already alluded to the loss sustained by the fermentation of dung-heaps. As we observed, in an earlier section, when it is con
sidered that, with every pound of ammonia | ations; as the difference of composition will, in which evaporates, a loss of sixty pounds of corn most cases, indicate the proper methods of imis sustained, and that, with every pound of provement. For instance, if, on washing a por urine, a pound of wheat might be produced, tion of sterile soil, it be found to contain largely the indifference with which liquid refuse is alany salt of iron, or any acid matter, it may be lowed to run to waste is quite incomprehensible. ameliorated with quicklime, which removes the That it should be allowed to expend its ammonia sourness, or, in other words, combines with and by fermentation in the dung-heap, and evapo- neutralizes the acid. For though pure fresh ration into the atmosphere, is ascribable solely burnt caustic lime is injurious to vegetation, yet, to ignorance of the elementary outliness of that in combination with acids, (as in chalk,) it science which hitherto the practical farmer has proves eminently serviceable. A soil, appathought it no disgrace, but rather an honor to rently of good texture, was put into the hands publish, glorying in his utter disregard of all of Sir Humphrey Davy for examination, said to bookish knowledge, and substituting his own be remarkable for its unfitness for agricultural notions of wasteful and vague experience, for purposes; he found it contained sulphate of the calm deductions of sound and rational inves- iron, or green copperas, and offered the obvious tigation.. .. It is by no means dif- remedy of top-dressing with lime, which deficult to prevent the destructive fermentation composes the sulphate. So, if there be an exand heating of farm-yard compost. The sur-cess of lime, in any form, in the soil, it may be face should be defended from the oxygen of the removed by the application of sand or clay. atmosphere. A compact marl, or a tenacious Soils too abundant in sand are benefited by the clay, offers the best protection against the air; use of clay or marl, or vegetable matter. To a and before the dung is covered over, or, as it field of light sand that had been much burnt up were, sealed up, it should be dried as much as by a hot summer, the application of peat was possible. If the dung be found at any time to recommended as a top-dressing; it was attendheat strongly, it should be turned over, anded not only with immediate advantage, but the cooled by exposure to air. Watering dunghills is sometimes recommended for checking the process of putrefaction, and the consequent escape of ammonia; but this practice is not consistent with correct chemistry. It may cool the dung for a short time; but moisture is a principal agent in all processes of decomposition. Water, or moisture, is as necessary to the change as air; and to supply it to reeking dung, is to supply an agent which will hasten its decay.
If a thermometer, plunged into the dung, does not rise much above blood-heat, there is little danger of the escape of ammonia. When a piece of paper, moistened with spirit of salt, or muriatic acid, held over the steams arising from a dung-hill, gives dense fumes, it is a certain test that decomposition is going too far; for this indicates that ammonia is not only formed, but is escaping to unite with the acid in the shape of sal-ammoniac.
When dung is to be preserved for any time, the situation in which it is kept is of importance. It should, if possible, be defended from the sun. To preserve it under sheds would be of great use, or to make the site of a dung-hill on the north side of a wall. The floor on which the dung is heaped, should, if possible, be paved with flat stones; and there should be a little inclination from each side towards the centre, in which there should be drains, connected with a small well, furnished with a pump, by which any fluid matter may be collected for the use of the land. It too often happens, that a heavy, thick, extractive fluid is suffered to drain away from the dung-hill, so as to be entirely lost to the farm.
good effects were permanent. A deficiency of vegetable or animal matter is easily discoverable, and may as easily be supplied by manure. On the other hand, an excess of vegetable matter may be removed by paring and burning, or by the application of earthy materials, &c., &c.
From what has been already said,
it will be easily evident, that the beneficial effect of the burnt ash is chiefly owing to the ready supply of inorganic and saline material it yields to the seeds which may afterwards be scattered there; besides which, the roots of weeds and poorer grasses, if not exterminated by the paring, are so far injured as to lead to their death and subsequent decomposition.
The improvement of peats or bogs, or marsh lands, must be preceded by DRAINING; stagnant water being injurious to all the nutritive classes of plants. Soft black peats, when drained, are often made productive by the mere application of sand or clay as a top-dressing. The first step to be taken, in order to increase the fertility of nearly all the improvable lands in Great Britain, is to DRAIN them. So long as they remain wet, they will continue to be cold. Where too much water is present in the soil, that food of the plant which the soil supplies is so much diluted and weakened that the plant is of necessity scantily nourished. By the removal of the superfluous water, the soil crumbles, becomes less stiff and tenacious, air and warmth gain ready access to the roots of the growing plant; the access of air (and consequently of the carbonic acid which the atmosphere freely supplies) being an essential element in the healthy growth of the most important vegetable productions. Every one knows, that when water In ascertaining the composition of barren soils is applied to the bottom of a flower-pot full of with a view to their productiveness, or of par- soil, it will gradually find its way to the surface, tially unproductive land in order to its amend- however light that soil may be: so, in sandy ment, they should be compared with fertile soils soils or subsoils in the open field. If water in the same neighborhood, and in similar situ- labound at the depth of a few feet, or if it so
EXAMINATION AND IMPROVEMENT OF SOILS.
abound at certain seasons of the year, such water will rise to the surface; and as the sun's heat causes it to dry off, more water will rise to supply its place. This attraction from beneath will always go on most strongly when the air is dry and warm, and so a double mischief will ensue: the soil will be kept cold and wet; and instead of a free passage of air downwards about the growing roots, there will be established a constant current of water upwards. Of course, the remedy for all this is an efficient system of drainage.
The following judicious observations found in a very brief chapter on Adver"Mineral Fertilizers" for the soil; tised which, in their vaunted universality of useful application, Mr. Smith seems to hold in about the same relative value as fashionable quack pills for all manner of diseases. He lays down, that "fertilizers" which do not either add to the soil what it originally wanted, or what has been abstracted from it by previous cropping, must do more harm than good. Yet he sees many advantages that may result from the skilful use of these "fertilizers." There must, however, in the first place, be a close examination of the soil, to ascertain the kind of medicament or sustenance that it requires, and then
Let us suppose that this is done, and that an artificial saline or mineral compost is judiciously and accurately put together, either to meet the deficiency, or added to a tolerably good soil to increase its fertility. The advantages of its use are not overstated in a recent pamphlet. 1st. It is cheap, compared with its value: a twenty shilling cask will supply an acre.
2d. It is light and easily carried, when compared with carting manure.
3d. It is suitable for small holders who cannot afford soiling, or keeping of cattle for making dung-heaps.
4th. It enables a tenant-at-will to take a good crop out of done-out land, if his landlord refuse
be wanting, although all the rest be supplied, the plants will not be brought to maturity. It is in vegetable as in animal life; a mother crams her child exclusively with arrow-root; it becomes fat, it is true; but alas! it is rickety, and gets its teeth very slowly and with difficulty. Mamma is ignorant, or never thinks that her offspring cannot make bone, or what is the same thing, phosphate of lime, the principal bulk of bone, out of starch. It does its best; and were it not for a little milk and bread, perhaps now and then a little meat and soup, it would have no bones and no teeth at all. Far
mers keep poultry; and what is true of fowls, wheat. If we mix with the food of fowls a is true of a cabbage, a turnip, or an ear of sufficient quantity of egg-shells, or chalk, which they eat greedily, they will lay many more eggs than before. A well-fed fowl is disposed to lay a vast number of eggs; but cannot do so without the materials for the shells, however A fowl, with the best will in the world, not findnourishing in other respects her food may be. ing any lime in the soil, nor mortar from walls, nor calcareous matter in her food, is incapacitated from laying any eggs at all. Let farmers lay such facts as these, which are matter of common observation, to heart, and transfer the analogy, as they justly may do, to the habits of plants, which are as truly alive, and answer as closely to evil or judicious treatment as their own horses.
The barren soil on the coast of Peru is rendered fertile by means of a manure called Guano, which is collected from several islands in the South Sea. It forms a layer several feet in thickness upon the surface of these islands, and consists of the putrid excrements of innumerable sea-fowl that remain on them during the breeding season. This substance has recently been imported in large quantities into England; and its fertilizing powers are very extraordinary. Its price, about £18 per ton, is a serious objection; and since the nitrogen it contains forms its principal recommendation, doubtless other matters nearer home will not be wasted, or their value remain unknown and disregarded, as to a great extent they have been. As to the practical results of the application of Guano, an intelligent agriculturist in the neighborhood of Hamburg has forwarded the annexed remarks to the Editor of the Gardener's Chronicle. He observes that "Most of the experiments with guano in the vicinity of this city have been made on meadows and lawns. On these it has
produced the best possible effects; so that, for with guano presented not only a finer and darker instance, at Flottbeck, the patches manured green, but the grass was closer and more rich; so that, comparing it with patches not guanized, the produce of the former may, without exaggeration, be stated to be double. To give an idea of the extraordinary forcing qualities of guano, we may mention, that at Flottbeck, on a spot of grass managed after the English fashion, the second cutting of the grass was necessarily five days after the first; while the grass growing close by, (which had not been