the Indian corn, which I have just spoken of.  In this instance, as also numberless others, sugar is formed in large quantities in the body of the plant, and elaborated into farina, or starch, in the ear.  The elements of which sugar and starch are composed are the same; the only difference is in their proportions.  Chemists, being aware of this, have converted starch into sugar; and could do it with certainty to any extent, were any advantage to be gained by it; but hitherto starch has been higher in price than sugar.

SECTION II.

THE GRAIN CROPS, EDIBLE ROOTS, AND FARINACEOUS PLANTS FORMING THE BREAD STUFFS OF COMMERCE.

The vegetable substances, from which man derives his principal sustenance, such as the nutritious cereal grains, the tuberous rooted plants and the trees yielding farina, are very widely diffused, and necessarily occupy the main attention of the cultivator; their products forming the most important staples of domestic and foreign commerce.  The cereal grasses and roots, cultivated in temperate regions, such as wheat, barley, oats, rye, and the potato, are so well known, and have been so fully described by agricultural writers that I shall not go much into details as to their varieties, culture, &c., but confine myself chiefly to their distribution, produce, statistics, and commercial importance.  The food plants may be most conveniently arranged under three heads.  Firstly—­the Grain crops and legumes, which comprises the European cultivated grasses, wheat, barley, oats, &c.; and the tropical ones of rice, maize, millet, Guinea corn, &c.  Secondly—­Palms and other trees yielding farina, including the sago palms, plantain and banana, and the bread fruit tree.  And Thirdly—­the edible Root crops and Starch producing plants, which are a somewhat extensive class, the chief of which, however, are the common potato, yams, cocos or eddoes, sweet potatoes, the bitter and sweet cassava or manioc, the arrowroot and other plants yielding starch in more or less purity.

There is a great diversity of food, from the humble oak bark bread of the Norwegian peasant, or the Brahmin, whose appetite is satisfied with vegetables, to the luxurious diet of a Hungarian Magnate at Vienna.

The bread stuffs, as they are popularly termed, particularly wheat and wheat flour, maize, and rice, form very important articles of commerce, and enter largely into cultivation in various countries for home consumption and export.  Russia, India, and the United States, carry on a very considerable trade in grain with other countries.  Our local production being insufficient for food and manufactures, we import yearly immense quantities of grain and flour.  In the four years ending 1852, the annual quantity of corn, of various, kinds, imported into the United Kingdom, exclusive of flour and meal, rice, sago, &c., averaged 8,085,903 quarters.

The flour and meal imported, omitting sago, arrowroot and other starches, averaged in the same period 4,143,603 cwts. annually.