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right in these conclusions, but may also, perhaps, find their parallels in the personal experience of some here present.
There is no department of scientific agriculture where a greater lack of precise and definite information is shown than in that of chemistry. This is partly the fault of enthusiastic writers on the subject, partly the result of imperfect teaching by those who are themselves not sufficiently familiar with the science which they are supposed to understand. I wish that upon this subject I could make myself heard and comprehended by every enlightened farmer in the United States; for all my observation and experience have led me to the conclusion that here is one of the most fertile, if not the most fertile, source of injury to the general cause of improved agriculture. It has been and still is believed by many farmers that this whole subject of chemistry is, to the initiated, as clear as noonday, and that the process of initiation is a simple and by no means lengthy one. The general idea seems to be, that in about the time that a young man can learn to shovel earth dexterously into a cart, he may also become capable of analysing a soil. You all know that a man cannot become a first rate plowman in one, or even two seasons; that those who take the highest rank must make it almost their business; but the mysteries of chemistry may be conquered in a few weeks, and a soil, after going through some mechanical process, just as certain to come out right as grain is to come out clean from a well constructed fanning mill. Gentlemen, this is a great and fatal mistake; I do not blame the farmers for it, but those scientific men, who, from interested or sincerely mistaken motives, have inculcated such views. That you may not think me extravagant, allow me, at the risk of being considered somewhat egotistical, to bring myself forward as an instance: I stand here to-night as a professed agricultural chemist; for the last seven years this has been, including, of course, other necessary connections of science with agriculture, my sole subject of study. The exceptions have been so few as to allow me to say that I have written upon nothing else, have worked upon nothing else, have studied nothing else. In this pursuit, too, I have, according to my own estimation, at least, been diligent, and may, perhaps without
question, claim to have acquired as much as the average of students would have done in the same time. Seven years then have been devoted almost exclusively to this study, and now at the expiration of that time you would be surprised if you could know my own real estimate of the knowledge gained in comparison with that which is yet to me a sealed book. This is no parade of false humility-no trick to call forth praise—it is perfectly sincere. The words of Newton must come up vividly to all who venture into the fields of science and begin to comprehend how vast and illimitable they are—how circumscribed the extent of our acquisitions in comparison with what lies beyond.
I say to you frankly, that when you meet with a man who makes all of these things easy, who pronounces with entire confidence upon every theoretical point, who reads his analysis of your soil, or plant, as you would read a book, distrust that man, for he is either intentionally imposing upon you, or he thinks he knows what he does not.
Did those who doubt this, ever seriously consider what the analysis of a soil, and the subsequent pronunciation of its defects or excesses in composition require? In the first place, the analysis itself is a matter of more difficulty than is generally supposed. The determination of the mineral substances in their exact quantities is a matter involving a necessity of somewhat extended experience. There are some among them respecting which we are even yet at fault. The most troublesome of these is phosphoric acid, a body with the name of which, at least you are all familiar, as of most importance to the farmer. It is somewhat difficult to separate phosphoric acid from its combinations so as to arrive at its precise quantity, and this is particularly the case when it is combined with several substances at once. Now, in the soil it is usually combined with iron, alumina, lime, and magnesia, just the worst set of companions, for the cheinist's purpose, that it could have chosen, as it is next to impossible to separate it from these accurately. Within the last few months a method has been devised, which seems likely to overcome this difficulty, but previous
to that, I do not hesitate to say that we had no method which was strictly accurate, as applied to soil analyses. I firmly believe that a guess, by means of certain tests, would have come as close to the reality as are many analyses that have been published. This is a specimen of the difficulties in one direction. If we turn to the organic or vegetable part of the soil we find ourselves at once involved in a maze or labyrinth of the most complicated description. Certain general and highly valuable principles have been established, but our knowledge of the strictly accurate analysis of this part is comparatively limited. We really are quite uncertain as to the true character and composition of humus, ulmic, geic, crenic and apocrenic acids, of which so much has been written; and I must confess that in the present state of our information I am disposed to attach little importance to any determination of them. But supposing all these obstacles were safely overcome, that all which exists in every part of the soil were safely and accurately determined and expressed by a long row of figures, have we arrived at the end of our difficulties ? by
We have now to consider what 'these figures mean with reference to the soil in its present state, and to the crops which grow upon it. In the first place, have we here a fair sample of the field ; if this be so we must ask, what has the physical character of the soil to do with the results of cultivation ?-is it wet or dry, stiff or light, mellow or tough, uneven and broken, or smooth ?-has it been cultivated properly, subsoiled, trenched, drained ? and what is the character of its subsoil ? Then, too, we must know what crops have prevailed, or what course of tillage has been adopted, and, as a necessary consequence, the composition or character of the manures employed ? Are not here a variety of subjects for inquiry; and are they not subjects whose satisfactory disposal would involve a great amount of study and perseverance. If there is no exaggeration here, (and I assure you there is not,) is not the complete analysis of a soil a matter involving much of difficulty, and something not to be undertaken after a few weeks' of preliminary practice? There is in fact room for the exercise of far more knowledge than we possess, or than any one possesses. I do not mean to say that the examination of all soils is attended
with these numerous obstacles, for there are many cases where a decision may be made easily and promptly; but there are others presenting questions which our present chemical science is incompetent to solve. I am a firm believer in the efficacy of soil analyses, but at the same time must acknowledge that our information in this department is still far short of what it should be. My own opinions upon their results are always given with hesitation and with qualifications, and each year makes me more cautious instead of bolder, more inclined to believe that our reading of nature's laws is still imperfect.
There are at this moment some of the most celebrated European chemists who argue that our present system of soil analysis is founded upon wrong principles and is almost worthless. Their views may be successfully opposed by the results of practice alone, yet the very fact of their being entertained in such quarters, shows that there is much of obscurity and uncertainty yet hanging about the subject.
Let the farmers of this State, then, insist on having persons who are properly qualified in this respect; do not encourage your young men who are practical farmers to indulge the idea of becoming chemists, or thoroughly scientific men. There is much in the way of science that they may most profitably study and practice upon, but they cannot usefully or advantageously go beyond the more elementary departments; he who cherishes, the desire to do: more than this, (and I would encourage every one who does,) must make chemistry his chief pursuit for a long period of time and under good advantages for instruction.
I hope that the need of science and the need of information in this department has now been made clear. The subject was selected as one of much interest to all of our more intelligent farmers, There is yet another, upon which I will touch as among the neces sities of our agriculture, and this is, the importance of satisfactory and accurate practical and experimental investigation. Those who have noticed the course of the public mind upon the subject
of agriculture for the past few years, must have observed the tendency to experiment that has rapidly developed• itself. As the conviction spreads that something is wrong, so does the desire to aid in making that wrong right, and the consequence is that we have been fairly inundated with records of practical experiments. What has resulted from the vast numbers of these experiments that have been zealously, and supposed to be carefully, made? Have we had any great principles brought out, any points established at all commensurate with the real expenditure of time and money involved? The records of most private and unassisted comparative experiments are extremely imperfect, and in many cases where both have evidently been conducted with a desire to arrive at the truth, they flatly contradict each other. We see in our agricultural papers endless controversies between good practical farmers, each of whom is fortified with his cases, and each of whom holds to his own belief with untiring tenacity, and with the most perfect good faith. Now, the difficulty in almost all of these cases is, that the experimenter has not sufficiently understood the nature of the materials with which he worked, or the various incidental circumstances which he ought to have taken into consideration.
Suppose A and B to be making experiments upon some particular crop in different counties, or to make the case even stronger, in different parts of the same town. It not very unfrequently happens, that fields or farms at trifling distances apart, have soils varying greatly in their character. A and B however, are not aware of this difference, or disregard it, and the consequence is a mysterious disagreement in their experiments, to the cause of which, the reader of their statement has no clue whatever. If we go a step farther, and suppose their soils to be very nearly alike, we still find new and abundant sources of discrepancy. One farm may be a little more elevated than the other, and the climate, therefore, somewhat different, it may be wetter, or the general cultivation may have been differently managed; these are all fertile and usually hidden sources of disagreement But if by some remarkable chance, for it is obvious that in view of the above neglected precautions, it it could be nothing more than a chance, these two experiments