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SCORE or more years ago, when Horace Greeley and Henry Ward Beecher were telling the American public what they knew about farming, there was quite a general tendency on the part of the agricultural class to hold up to ridicule what was termed "scientific farming." Great claims were then made as to the importance of a knowledge of science, so that the farmer might analyze the soil, crops, fertilizers, etc. Especial stress was laid upon having a knowledge of chemistry, in order to be able to analyze something. Chemistry was to be the panacea for all the farmer's ills, and writers indiscriminately quoted Liebig, Boussingault, Johnston, Lawes, and Gilbert, and other famous agricultural chemists. There was much book farming done that was a source of amusement for practical agriculturists. Much of the written matter and advice • published was worthless, and time and the labors of science conclusively demonstrated as much. Early investigators, engaged in faithful and hard work, gleaned much information of scientific importance, and eventually overturned numerous theories that had hitherto seemed plausible. Chief among these was the analysis of soils, whereby one could know the composition of his soil and at once determine in what ingredients of plant food it was deficient, so that he might feed back to it the lacking elements. Time and study have shown that soil is a very complex substance, and one analysis is usually quite unsatisfactory, because a little sample of soil represents only a small piece of ground, perhaps representing quite unfairly the entire field. Consequently, as remarked by Dr. Caldwell, soil analyses are not thoroughly practical, on account of the difficulty in securing a sample of a few pounds that shall correctly represent the millions of pounds of soil in even a single acre, to say nothing of a field of many acres.

Fifty years ago Justus von Liebig, a German chemist, through an interest in rural economy which resulted in far-reaching discoveries, established himself as the father of agricultural chemistry. His investigations largely related to the composition of the soil and plant nutrition. He was the first to prove that plants fed on certain ingredients of the soil, and that different classes of soils and plants varied in their composition. Liebig's was the pioneer work, and from his time to the present a mass of scientific information has been gradually accumulating that in numerous ways is serving a good purpose.