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world. Among ourselves it would be vain, in the present youth of the country, to attempt to calculate the extent to which the art is destined to be carried. The forthcoming census of its agricultural products will exhibit results, which will excite universal surprise. An annual crop, in the Southern States, of more than 2,000,000 bales of cotton, of 249,000,000 pounds of sugar in Louisiana, of 42,000,000 bushels of Indian corn in Tennessee, of 18,000,000 busbels of wheat in Ohio, and more than 10,000,000 pounds of maple sugar in New York, great as these results appear, are yet only the first steps in the progress of this gigantic in
These facts show how essentially agriculture concerns the condition of the whole country. This interest, likewise, is certain to increase in an equal ratio with the growth of her population; and let her commerce be ever so extended, or her manufactures as numerous and improved as invention and skill and art can make them, yet they must always be subsidiary to her agriculture. It is her agriculture which freights the barks of commerce, and drives the wheels and spindles of her manufactories in their rapid and infinite gyrations. At her breasts, without a single exception, the whole of the human family are to be sustained, nourished, and comforted.
The perfection of agriculture, as an art, implies the obtaining the greatest amount of product from the earth, with the least injury to the land, and at the least cost of labor. It has been often remarked, that the actual productive powers of an acre of land have never yet been fully tested; the maximum of product has not been reached. Magnificent and surprising results have been attained, but in no case can it be said, with confidence, that more might not have been effected. In general, the agricultural art falls far below the condition of productiveness and improvement, which it might obviously attain ; and the aversion among farmers to change their established habits, and the slowness with which agricultural improvements of great and decided advantage extend themselves, even into neighbouring districts, are well known and sufficiently remarkable. Something of this has been owing to the stationary habits of farmers, 10 a want of education, and neglect of reading and inquiry necessarily growing out of this, and much to prejudice, the natural child of ignorance, against scientific suggestions and the application of
science to an art, which, so far as they are concerned, is wholly of a practical character. This prejudice against the applications of science to agriculture, or to what in vulgar parlance is called book-farming, has, we confess, found some natural encouragement in the fact, that many persons, wholly destitute of practical knowledge and skill, have undertaken to apply purely theoretical rules, without regard to differences of soil, climate, nature of the crop, and nameless circumstances by which the application of these rules should be varied, or might be rendered unseasonable or futile ; and that, in truth, many persons have undertaken to make books, and to give directions in husbandry, who were grossly ignorant of its great principles, and possessed little knowledge of its various practical details and rules. It must, at the same time, be admitted, that science has as yet accomplished but little ; and that, beyond that knowledge which any intelligent, practical, and experienced man easily and almost necessarily acquires of soils, manures, vegetation, and crops, little has been ascertained of a practical value ; and the profound secrets of vegetable life, or what is properly termed vital action in vegetable organism and growth, remain in all their original abstruseness and mystery. The little success, therefore, which scientific men have had in their attempts to resolve and explain them, and especially the little practical utility which has come from their theoretical explanations, have created, with the purely practical, a prejudice against such inquiries, as invincible as it is unworthy of sensible men.
Yet it will not be denied, in this case, that we know as much of vegetable as we know of animal life. Anatomy may be termed an exact science; it is to a great extent matter of sensible observation and measurement ; but the operations in the human organism, which are strictly vital, are altogether undisclosed. We know in truth as much how the stems and leaves and fruit are formed and perfected, as we know how the food, which we receive, is converted into blood, and serum, and bile, and muscle, and fibre, and tendon, and bone ; and we know no more. Shall we despair of going further ? By no means. There seems, indeed, in this case, to be a limit to inquiry; an impassable barrier, where human sagacity and inquisitiveness are at once repelled ; the darkness is intense before, above, and around us, and the mere rush-light, which we hold out to guide us, serves no
but to render this darkness visible. Shall we then be discouraged in all attempts at further advancement ? Not at all. It may be indeed that we have reached the end of our line ; and that, until new endowments are bestowed, the mind can soar no higher in its flight. But with equal, nay, with much more reason may we suppose, that the cause of failure is not so much attributable to the limitation or impotence of our faculties to proceed further, as to the imperfection or error of our modes of approach and inquiry. The philosophical mind, valuing truth and knowledge as the highest of all attainments, will never rest satisfied with present acquisitions ; will regard that which is conceivable as knowable ; like a vigilant and skillul officer before a besieged fortress, whose direct approach is precluded, will be continually seeking some private or concealed mode of access ; or, like the man in the Scriptures knocking at his neighbour's door at midnight, and hoping presently to be heard for his importunity.
The immense importance and value of knowledge in this case no sensible man can doubt. If knowledge and science are useful in any art or department of business, why should they not be in agriculture, an art which involves many others, and which in its success combines the influence and operation of more elements than any other ? It is well ascertained that certain plants will grow only in certain situations, and under certain circumstances ; that different soils have different properties, prejudicial to the growth of some plants, favorable to the perfection of others ; in some cases distinguished by an exuberant fertility, in others by an almost incurable barren. ness, but yet in most cases capable of modification, remedy, or improvement ; that the operation of various manures is various; and that their efficiency or injury depends upon their condition, preparation, or modes of application. It is equally well ascertained, that by some modes of cultivation, double the produce is obtained on the same land that is obtained under a different cultivation, and the land, at the same time, placed under a progressive improvement. It is ascertained that by the application of gypsum, or potash, or soda, or salt, or various animal substances, an extraordinary productiveness follows, and the crops are often trebled and quadrupled. How shall we pretend, then, that there is not here the most ample room for the application of science in the resolution of these remarkable facts, and in profiting by these remarkable means for the improvement of the soil and the increase of its productiveness ? Separate, however, from the obvious utility of such inquiries, it is difficult to conceive of subjects more interesting to a philosophical curiosity than all those connected with animal or vegetable life and growth; for what in nature is more wonderful than the birth and progress of a human being, or the germination of a dried seed and its advancement to the perfection of its uses and fruits ?
There are besides grounds of encouragement in this case, which the philosophical mind will duly appreciate. In the ordinary course of nature there is no such thing as accident or miracle. As far as man's sagacity has penetrated into the material world, — and of the spiritual world, we know nothing but by divine revelation, — all the
all the phenomena of nature are found to proceed upon fixed principles and laws, and to be the results of nicely established and well balanced, compounded, and adjusted influences and forces. Many of these operations man is capable of imitating, and the most extraordinary results are obviously at his command. We cannot have a doubt, therefore, that the most recondite as well as the most familiar operations of nature are all the result of established principles and laws. Many of these laws we have already ascertained, and they are of daily application and use in the common business of life.
How much further we may proceed in the discovery of them, time only can tell. As yet we have only placed our foot on the first step of the threshold. It is not an idle nor criminal presumption to seek to penetrate further into the temple of nature, until perhaps we may reach the Holy of Holies, where the Creator sits enthroned in his effulgence, and where we may adore him in the full blaze of truth.
· Professor Liebig illustrates the spirit of which we speak. He is a bold inquirer of nature for the laws which govern her operations. He is for explaining the phenomena of vegetable lise and growth upon the established principles of chemistry, as far as their application can be traced ; and he is not willing to take a general answer where a particular answer can be obtained. He does not feel satisfied to be checked in his inquiries under the presumption of inexplicable mystery, when further inquiry would untie the Gordian knot, and show that some of the problems, hitherto considered most difficult, are perfecily explicable upon the established principles of chemical science.
" A rational system of agriculture,” says he, " cannot be formed without the application of scientific principles ; for such a system must be based on an exact acquaintance with the means of nutrition of vegetables ; and with the influence of soils and the action of manure upon them. This knowledge we must seek from chemistry, which teaches the mode of investigating the composition, and of studying the characters, of the different substances from which plants derive their nourishment."
" Innumerable are the aids afforded to the means of life, to manufactures and to commerce, by the truths which assiduous and active inquirers have discovered and rendered capable of practical application. But it is not the mere practical utility of these truths, which is of importance. Their influence upon mental culture is most beneficial ; and the new views acquired by the knowledge of them enable the mind to recognise in the phenomena of nature proofs of an infinite wisdom, for the unfathomable profundity of which human language has no expression.”
The work is devoted to an explanation of the proper food of plants, and the modes in which, and sources from which, they receive this nourishment. Connected with these matters, come, of course, the value and uses of manures, and the true art of culture. These subjects are all obviously of the highest importance; and it is exceedingly interesting to see how a mind so powerful and learned discusses them. The author speaks with just respect of that distinguished man, the late Sir Humphrey Davy, who first taught systematically the application of chemical science to agriculture ; and he shows himself not an unworthy pupil of so eminent a master. We can do but imperfect justice by an abstract of his views; yet it is all for which we have room.
The elements or constituents of all plants are carbon, water, (or its elements, hydrogen and oxygen,) nitrogen, and some earthy or alkaline salts. The food of plants can be received only in a gaseous or soluble form, and it must come from the atmosphere, from the earth, or from both. No earthy substance can ever be received into a plant unless in a dissolved or combined state ; and though crude substances, incapable of assimilation, may in some cases be taken up by the roots of the plant, which seem to have no power of selection in regard to their food, yet they will be exuded from the roots in the state in which they were received. The alkaline substances received and assimilated by plants can only be as