METEOROLOGY.

METEOROLOGY IN ITS CONNECTION WITH AGRICULTURE.

BY PROF. JOSEPH HENRY, SECRETARY OF THE SMITHSONIAN INSTITUTION.

We intended, in this number of our contributions to "Meteorology as applied to Agriculture," to give an account of the distribution of rain, of the phenomena of storms, and other matter pertaining to the climate of the United States; but the colored plates necessary to illustrate this subject were not ordered by Congress at its last session, and, therefore, we are obliged to change our plan. We have concluded to occupy the space allowed us in the Report of the Patent Office, with a more definite exposition of some of the general principles of science, especially applicable to meteorology, than is generally met with in elementary works. We are induced to adopt this course on account of the inquiries which we are constantly receiving in regard to subjects of this class from all parts of the country; a great interest having been awakened during the last few years in the study of meteorology, principally through the efforts of the Smithsonian Institution and the Patent Office. We trust that our essay will be acceptable to the agriculturist, since, however remote the theoretical part of the communication may appear, at first sight, from his pursuits, yet a proper view of the relation of science and art will enable him to see that the one is dependent on the other, and that each branch of the study of Nature is intimately connected with every other.

We take it for granted that the American farmer is capable of logical reflection; that he is not content with the ability merely to perform with facility agricultural operations, and to direct with skill the ordinary routine of his farm, but that he is, also, desirous of knowing the rationale or scientific principles of all the processes he employs. We have no sympathy with the cant of the day with reference to "practical men," if by this term is understood those who act without reference to well-established general laws, and are merely guided by empirical rules or undigested experience. However rapidly and skilfully such a person may perform his task, and however useful he may be within the limited sphere of his experience, and in the practice of rules given by others, he is incapable of making true progress. His attempts at improvement are generally not only failures, involving a loss of time, of labor, and of materials, but such as could readily have been predicted by any .one having the requisite amount of scientific information. It is the due combination of theoretical knowledge with.

practical skill which forms the most efficient and reliable character, and it should be the object of the agricultural colleges which are about being established in various parts of our country to produce educational results of this kind.

It is not expected that the farmer is to be a professional scientist, but that he should be familiar with the general principles of all branches of knowledge which more especially relate to his occupation; and the wider the extent of his information, the better. Above all, he should be qualified to form a just appreciation of the value of original scientific investigations, and be ready at all times to adopt the principles which they may unfold, so far as they may be applicable to his uses; and, moreover, be willing to render a due acknowledgment for the benefits thus conferred, and to contribute in any way in his power to the necessary, if not liberal, support of those who seek, without the hope of pecuniary reward, to advance the bounds of human knowledge and of human power. The number of those in any age, and in any country, who successfully investigate Nature and discover new truths, which form valuable contributions to the existing stock of knowledge, is comparatively small. The successful labor of the hands is much easier than that of the head; and, therefore, those who have actually proved by what they have done that they possess the ability to enlarge the field of science, should be especially cared for, and their energies husbanded and directed to the one pursuit to which they may have devoted their attention. Unfortunately, however, there has always been in England and this country a tendency to undervalue the advantages of profound thought, and to regard only with favor those investigations which are immediately applicable to the wants of the present hour. But it should be recollected that the scientific principles which at one period appear of no practical value, and are far removed from popular appreciation, at another time, in the further development of the subject, become the means of individual prosperity and national wealth.

About fifty years ago Sir Humphrey Davy moistened a small quantity of ordinary potash, and, submitting it to the current of a powerful galvanic battery, observed a number of brilliant particles burning and exploding on the surface. With the intuitive perception of a highly philosophical mind, he saw at once, in this experiment, a fact of the deepest significance-the verification of a previous a priori hypothesis, namely, that potash and the other alkalies and alkaline earths were not simple substances, as they had previously been considered, but metals compounded with oxygen. This discovery, which had an important bearing on the whole science of chemistry, but which had no interest for the popular mind, has, in the course of time, revolutionized many of the processes of art, and will furnish the means, in various ways, of adding to the comforts and conveniences of life. Within the last two years a French chemist has discovered a process of decomposing one of these alkaline earths, namely, the clay, which forms the basis of the soil of the farmer, and which, hardened by fire, constitutes the brick to build his tenement, and of obtaining from it a metal as light as glass, as malleable and ductile as copper,

and as little liable to rust as silver. These discoveries were made by men whose lives were devoted to the abstract study of Nature; they are not the results of accident, but logical deductions from previous conceptions of the mind, verified and further developed by the ingenious processes of the laboratory. It may be safely said, that for every one individual who is capable of making discoveries of this kind, there are at least a thousand who can apply them to useful purposes in the arts, and who will be stimulated to undertake enterprises founded upon them by the more general and powerful incentive of pecuniary reward. When the When the process of procuring aluminum, or, in other words, the metal from clay, has been perfected, and some enterprising citizen shall have established a great manufactory for the production of the article for general use, he will have conferred. a benefit on his country, be entitled to credit, and will probably receive the desired remuneration. But should the names of the chemists who originally made the discovery of the principles on which this public benefit depends be forgotten? Ought not their labors to enlarge the bounds of knowledge to be properly valued, and their names held in grateful remembrance? If living, should they not be afforded the means of extending their investigations, without the distraction of mind attendant on the efforts to obtain a precarious livelihood for themselves and families?

In truth, we must say, not in the way of complaint, but for the purpose of drawing attention to the fact, and with the hope of somewhat changing the condition of things in this respect, that in no civilized country of the world is less encouragement given for the pursuit of abstract science than in the United States. The general government has no power in the Constitution directly to foster pursuits of this kind; and it is only by an enlightened public opinion, and the liberality of wealthy individuals, that a better condition of things can be hoped for.

The great facts of the future of agriculture are to be derived from the use of the microscope, the crucible, the balance, the galvanic battery, the polariscope, and the prism, and from the scientific generalizations which are deduced from these by the profound reflections of men who think, in contradistinction to those who act. The intelligent farmer should be able, as we have already said, properly to appreciate the value of scientific discoveries; and for this purpose his studies should not be confined merely to rules or empirical receipts, but also to the general principles on which they are or should be founded.

Though some of the points we shall discuss in the following essay may appear, at first sight, to be of too abstract a character to be comprehended by a casual reader, yet they will be found, on attentive perusal, by a person of ordinary intelligence, to be easily understood; but it may be well here to call attention to a fact frequently overlooked, that there is a great difference between reading and study, or between the indolent reception of knowledge without labor, and that effort of mind which is always necessary in order to secure an important truth and make it fully our own.