After more than twenty years of peaceful intercourse, the war of 1846 broke out between Mexico and our Union. Thousands, of all classes, professions and occupations,—educated and uneducated—observers and idlers,—poured into the territory of the invaded republic. In the course of the conflict these sturdy adventurers traversed the central and northern regions of Mexico, scoured her coasts, possessed themselves for many months of her beautiful Capital, and although they returned to their homes worn with the toils of war, none have ceased to remember the delicious land, amid whose sunny valleys and majestic mountains they had learned, at least, to admire the sublimity of nature. The returned warriors did not fail to report around their firesides the marvels they witnessed during their campaigns, and numerousworks have been written to sketch the story of individual adventure, or to portray the most interesting physical features of various sections of the republic. Thus by war and literature, by ancient curiosity and political sympathy, by geographical position and commercial interest, Mexico has become perhaps the most interesting portion of the world to our countrymen at the present moment. And I have been led to believe that the American people would not receive unfavorably a work designed to describe the entire country, to develop its resources and condition, and to sketch impartially its history from the conquest to the present day.