Lectures on the applications of chemistry and geology to agriculture ...

Front matter

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Preface

The First Part of the following Lectures was addressed to a Society* of practical agriculturists, most of whom possessed no knowledge whatever of scientific Chemistry or Geology. They commence, therefore, with the discussion of those elementary principles which are necessary to a proper understanding of each branch of the subject. Every thing in such Lectures, which is not — or may not be — easily understood by those to whom they are addressed, is worse than useless. It has been my wish, therefore, to employ no scientific terms, and to refer to no philosophical principles, which I have not previously explained.

To many who may take up the latter portions of the work, some points may appear obscure or difficult to be fully understood ; such persons will, I hope, do me the justice to begin at the beginning, and to blame the Author only when that which is necessary to the understanding of the later is not to be found in the earlier Lectures.

For the sake of clearness, I have, in the following pages, divided the subject into four Parts — the study of each preceding Part preparing the way for a complete understanding of those which follow. Thus, Part I. is devoted to the organic elements and parts of plants, the nature and sources of these elements, and to an explanation of the mode in which they become converted into the substance of plants ; — Part II., to the inorganic elements of plants, comprehending the study of the soils from which these elements are derived, and

* The Durham County Agricultural Society, and the Members of the Durham Farmers' Club.

VI PREFACE.

the general relations of geology to agriculture ; — Part III., to the various methods, mechanical and chemical, by which the soil may be improved, and especially to the nature of manures^ by which soils are made more productive, and the amount of vegetable produce increased; — and Part IV., to the results of vegetation^ to the kind and value of the food produced under different circumstances, and its relation to the growth and feeding of cattle, and to the amount and quality of dairy produce.

By this method I have endeavoured to ascend from the easy to the apparently difficult ; and I trust that the willing and attentive reader will find no difficulty in keeping bv niy side during the entire ascent.

The Author has much pleasure in now presenting these Lectures to the public in a complete form-. He has only to express a hope that the delay which has occurred in the publication of the latter part of the work has enabled him to render it more useful, and therefore more worthy of the public approbation.

Note. — The rapid sale of a large impression having rendered a second edition of the first and second Parts necessary hefore the entire completion of the work, such alterations, corrections, and additions only have been made as could be introduced without altering the original paging of the work. Several oversights, however, have been corrected, and some omissions supplied, which presented themselves in the earlier edition.