PLAN OF THIS WORK.

THE growing demand for the species of practical information which it has bee our object in the following pages to concentrate, has often suggested itself to the author, and doubtless to numberless others. Perhaps in no country have more frequent inquiries been made in relation to COAL; to its infinite varieties, adaptations and modifications; its innumerable depositories and its geographical distribution, than in the United States of America.

This desire, probably, originates in the circumstance that in no country has such rapid progress been made in the development of mineral fuel, not only for all domestic purposes, but as a powerful agent in every department of manufacturing industry; notwithstanding that enormous and almost unbroken forests still overshadow the land. The increasing demand and corresponding supply, the rapid expansion of the field of industrial operations, have no doubt awakened this solicitude for information-local, general, statistical, commercial and scientific, on the subject of coal.

We have reason, however, to be assured that the demand for this species of knowledge is not limited to the country from whence we date. It prevails more or less in every quarter of the globe where that inestimable substance has been investigated and brought into the service of man. It was obvious that a statistical work, embodying all the important details in relation to the mineral combustibles of the world, would be an acceptable contribution to practical science.

Until some such work appeared, it were a fruitless task to seek for details which no one had undertaken to collect in the compass of a single volume; and which yet remained, like the mineral itself, scattered throughout all the countries of the earth.

Acting under this impression the author has sought and gathered together the materials-a great number at least, to remedy the deficiency of which we speak.

His design, at the outset, was limited to the collection of such coal statistics as seemed sufficient for his private guidance. As in all labours of this description, the materials, during the progress of the undertaking, accumulated to an extent far greater than was anticipated. An extended arrangement led to greatly increased labour. The sources of information as regards foreign countries, being remote, its acquisition is necessarilly uncertain and tedious: