_My seventh geological argument for the divine benevolence is derived from the manner in which coal, rock salt, marble, gypsum, and other valuable materials were prepared for the use of man, long before his existence._
If a created and intelligent being from some other sphere had alighted on this globe during that remote period when the vegetation now dug out of the coal formation covered the surface with its gigantic growth, he might have felt as if here was a waste of creative power. Vast forests of sigillaria, lepidodendra, coniferæ, cycadeæ, and tree ferns would have waved over his head, with their imposing though sombre foliage, while the lesser tribes of calamites and equisetaceæ would have filled the intervening spaces; but no vertebral animal would have been there to enjoy and enliven the almost universal solitude. Why, then, he must have inquired, is there such a profusion of vegetable forms, and such a colossal development of individual plants? To what use can such vast forests be applied? But let ages roll by, and that same being revisit our world at the present time. Let him traverse the little Island of Britain, and see there fifteen thousand steam engines moved by coal dug out of the earth, and produced by these same ancient forests. Let him see these engines performing the work of two millions of men, and moving machinery which accomplishes what would require the unaided labors of three or four hundred millions of men, and he could not doubt but such a result was one of the objects of that rank vegetation which covered the earth ere it was fit for the residence of such natures as now dwell upon it. Let him go to the coal fields of other countries, and especially those of the United States, stretching over one hundred and fifty thousand square miles, containing a quantity absolutely inexhaustible, and already imparting comfort to millions of the inhabitants, and giving life and energy to every variety of manufacture through the almost entire length of this country, and destined to pour out their wealth through all coming time, long after the forests shall all have been levelled,--and irresistible must be the conviction upon his mind, that here is a beautiful example of prospective benevolence on the part of the Deity. In those remote ages, while yet the earth was unfitted for the higher races of animals that now dwell upon it, it was eminently adapted to nourish that gigantic flora which would produce the future fuel of the human race, when that crown of all God's works should be placed upon the earth. Ere that time, those forests must sink beneath the ocean, be buried beneath deposits of rock thousands of feet thick. But during all that period, all those chemical changes which are essential to convert them into coal would be accomplished, and, at last, man would find access, by his ingenuity and industry, to the deep-seated beds whence his fuel might be drawn. Nor would these vast repositories fail him till the consummation of all things. Surely there was no waste, but there was a far-reaching plan of benevolence in the profusion of vegetable life in the earlier periods of our planet.