Читать книгу Star-land: Being Talks With Young People About the Wonders of the Heavens онлайн

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Poke up the fire, and while it is throwing forth that delicious warmth, and charming but flickering light, we will try to discover where that light and heat have come from. No doubt they have come from the coal, but then, whence came the coal? It came from the mine, where brave colliers hewed it out deep under the ground, and then it was hoisted to the surface by steam engines. Our inquiry must not stop here, for another question immediately arises, as to how this wonderful fuel came into the earth? When we examine coal carefully, by using the microscope to see its structure, we find that it is not like a stone; it is composed of trees and other plants, the leaves and stems of which can be sometimes recognized. Indeed, the fossil trunks and roots of the great trees are occasionally conspicuous in the coal-pit. It is quite plain that these are only the remains of a vegetation which was formerly growing and flourishing, and on further inquiry we learn that coal must have been produced in the following manner:—