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IMPORTANCE OF THE STUDY OF CHEMISTRY. 
Adverting to the alliance between agriculture and chemistry, 
Dr. Hofmann says : 
_ To keep up the fertility of his fields, the cultivator of the soil had to make 
himself acquainted with its general composition, as well as with the nature 
both of the particular substances, which lie is annually extracting from 
it, and of those with which he must supply the loss. For each of these 
purposes the aid of chemistry became indispensable to the farmer. Davy’s 
excellent work on agricultural chemistry first called the attention of the 
more intelligent British farmers to the value of chemistry in the improve¬ 
ment of their art, but it is only within the last twenty years that the atten¬ 
tion of agriculturists has been generally directed to the subject, more par¬ 
ticularly by the works of Liebig and Boussingault. The nature of manures 
once clearly defined, almost every agricultural improvement at which practice 
had arrived by slow degrees, received a satisfactory explanation, whilst a 
variety of improved applications necessarily suggested themselves. The 
principles of fallowing and of the rotation of crops, and the theory of soil¬ 
burning, are no longer mysteries; the action of lime, of wood ashes, and 
of bones is now perfectly intelligible. In this country, too high a value 
cannot be set upon the discovery of new sources of material convertible by 
the farmer into human food. Chemistry has put us in possession of the 
excreted wealth, which centuries had accumulated in the islands of the 
Pacific; and if the means which it has suggested for preventing the enor¬ 
mous waste of valuable matter perpetually and irrevocably swept away by 
the Thames and others of our large rivers, have not as yet been perfectly 
successful, it has enabled us to substitute for natural manure, artificial pro¬ 
ducts, for the components of which the refuse of every trade and manu¬ 
facture is now carefully sifted. Perhaps there is no more striking illustration 
of the value of the aid which agriculture has derived from her new ally, 
than the success which of late has attended the search for mineral manures. 
This search, directed by the philosophical interpretation of a few isolated 
facts, has been rewarded by the discovery of considerable quantities of 
phosphate of lime in various parts of England; thus realising the prophetic 
anticipation of Liebig, that ‘‘in the remains of an extinct animal world, 
England is to find the means of increasing her wealth in agricultural pro¬ 
duce, as she has already found the great support of her manufacturing 
industry in fossil fuel, the preserved matter of primeval forests, the remains 
of a vegetal world.” 
After this, we are brought to a section which perhaps will 
by some of our readers be considered the most important, 
although all are but as links in a chain, each giving to the 
other strength and contributing to the usefulness of the whole. 
Nor is the increase of his vegetal produce the only object in the pursuit 
of which the farmer relies upon the counsels of the chemist; in the feeding 
and fattening of his animal stock, he stands in no less need of his instruc¬ 
tion. 
And here we may briefly allude to the benefits, which physiology, pathology, 
nd medicine in general, have derived, and must still further derive, from the 
prosecution of chemical inquiry. The investigation of the food of plants was 
followed by a no less vigorous scrutiny of the food of animals. The materials 
consumed by animals were shown to fulfil two distinct purposes in their 
economy, enabling us at once to separate into two distinct classes the sub¬ 
stances supplying,—each respectively,—the aliments of nutrition, and those 
of respiration. In vegetal fibrin and albumen, we became acquainted with 
a group of nitrogenous compounds, which we find again in the animal 
