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reason, its intelligence, its energy, its freedom, which first ordained the laws of matter, and still controls, uses, and subordinates these laws to its higher purposes and nobler ends.

Man, then, is above nature because there is an essence, an entity, in him which is supernatural. His will is a power which can act upon the chain of cause and effect in nature. He can control and direct the forces of nature. He can so collocate and adjust the properties and forces of nature as to accomplish ends which he designs, and bring about new results which nature, by her own internal working, could never have produced. If these propositions are established, then all objections to the revealed doctrine of a Providence, and of the direct interpositions of God in a supernatural way to instruct and save man, are rendered innoxious, and deprived of all force.

We shall present our proofs and illustrations in the following order:

I. The power of man in modifying the physical geography of the globe.

II. The influence of mind on the physiognomy of the earth.

III. The influence of mind on the physique of man.

IV. The power of mind to control and subordinate the mechanical, chemical, and electrical forces in nature.

V. The influence of mind on the vegetable life of the globe.

VI. The power of man over the instincts, habits, and development of the animal creation.

I. The power of man in modifying the physical geography of the globe.

Physical Geography deals: 1st, With the general features of the earth's surface-its mountains and rivers, its continents and seas; 2d, The atmosphere which surrounds it-its winds, rains, and climate; 3d, With the distribution of its vegetables and animal life-its zoological and botanical regions.

Now that man, by his intelligent action, has exerted a very great influence in modifying the climate of a country, and materially extending or materially circumscribing the geographical boundaries of a great number of plants and animals,

has been fully proved by Lyell, and still more amply shown by Marsh.

There can be no doubt that the increase and diminution of vegetation has a large influence on the climate of a country. The gradual spreading of forests will increase the humidity of the atmosphere. The felling of timber will materially diminish it. "In tropical countries, especially where the quantity of aqueous vapor in the atmosphere is great, and, at the same time, the direct rays of the sun are most powerful, the trees are an impediment to a free circulation of air, and screen the earth from the solar rays-they are thus a source of humidity; and where dampness and cold have begun to be generated by such causes, the condensation of vapor continues. Accordingly the cutting down of forests has been attended in many countries by the diminution of rain, as in Barbadoes and Jamaica.* It is also affirmed that in olden times, when France and England were covered with timber, Europe was much colder than at present. The winters in Italy were much colder than they are now. The Seine and many other rivers were frozen over every winter, and, in the fifteenth century, the Thames was commonly frozen so thick that the inhabitants could cross over in wagons from London to Southwark, and fairs were held regularly upon the ice. The clearing of the forests, by raising the temperature, and increasing the dryness of the air, reacts upon the climate.t In Palestine and many other parts of Asia and Northern Africa, which in ancient times were the granaries of Europe, fertile and populous, the most disastrous consequences have resulted from the destruction of the forests. "These lands are now deserts, and it is the destruction of the forests alone which has produced the desolation."

On the other hand, examples are not wanting of the beneficial influence of planting and restoring the woods. "In Scotland, where many miles square have been planted with trees, this effect has been evident, and similar observations have been made in several parts of Southern France. In Lower Egypt, both at Cairo and Alexandria, rain rarely fell in considerable quantities. For example, during the French occupation of Egypt, about 1798, it did not rain for sixteen months; but since *Lyell's "Principles of Geology," p. 713.

+ See Marsh's "Man and Nature," pp. 160, 161. FOURTH SERIES, VOL. XXII.—3

Mehemet Ali and Ibrahim Pacha executed their vast plantations, (the former alone having planted more than twenty millions of olive and fig trees, cottonwood, oranges, acacias, planes, etc.,) there now falls a good deal of rain, especially along the coast, in the months of November, December, and January; and even at Cairo it rains both oftener and more abundantly, so that real showers are no rarity." *

The application of human skill and labor in the draining of lakes and marshes, the reclamation of waste lands, and the cultivation of the soil, has exerted an appreciable influence upon the climate. Intermittent fevers have disappeared from England, chiefly, no doubt, in consequence of the careful drainage and high cultivation of the land. Two centuries ago they were as prevalent in England as they are now in the western States of America. Cromwell, Milton, and Bunyan died of intermittent fever. Fever and ague lingered in the fens of Lincolnshire until the commencement of this century. But the fens have been perfectly drained at the public expense, and that type of disease is now unknown in England.

The influence which man has exerted in extending or in contracting the geographical boundaries of plants and animals is still more marked and decided. It is known to our readers that there are distinct and well-defined botanical provinces and zoological regions which are the proper home and habitat of distinct species. These limits have been circumscribed, overleaped, and greatly modified by man. The stag, the wild. horse, the boar, the bear, and the beaver have been exterminated in England. The eagle, the larger hawks, and the ravens have disappeared. The bustard, the bittern, the mallard, and the snipe, once so numerous, are now rarely seen. So the buffalo has become extinct in the Eastern and Middle States, and the deer is rapidly disappearing from all our forests.

While man has been circumscribing the limits and is threatening to extirpate many species of plants and of animals, he has been rapidly diffusing others over a wider area. He transports with him into every region the vegetables he cultivates for his food, and the animals he employs for his convenience. "The species of plants and animals originally inhabiting the eastern and western hemispheres were probably almost entirely differ

• Marsh's "Man and Nature," p. 189.

ent, until the agency of man changed their geographical distribution; and almost the same may be said of the species north and south of the equator."* There is no question that wheat and the coffee-plant are indigenous to the Old World, and that the potato and the maize had their origin in the New. But they have been interchanged by man, and carried over the globe. Wheat is now cultivated in Europe, in North and South America, in New Zealand, Australia, and at the Cape of Good Hope. The potato is cultivated in almost every land. Coffee is largely grown in both hemispheres, and maize is cultivated in abundance both in the North and the South.

The most striking illustration of the influence of man in the distribution and naturalization of species of plants and animals is found in the fact that, in Australia, New Zealand, Southern Africa, and North America, the aboriginal European species of plants exceed in number all those which have come from all other regions, just because the Anglo-Saxon race has carried them along in its migrations. When Australia was first discovered, the land quadrupeds belonged exclusively to the marsupials—as the kangaroo, wombat, and flying opossom, and the native fruits and vegetables were not adequate to sustain human life.t But man has introduced the sheep, the alpaca, the horse and oxen; the latter have become so numerous as to fill some of the forests with wild cattle. Now wheat, barley, oats, Indian-corn, are extensively cultivated. The apple, the pear, the plum, and the peach have been naturalized, and culinary vegetables are abundant.

The extraordinary herds of wild cattle and horses which overrun the plains of South America are descendants from a few pairs carried there by the Spaniards. And in the Islands of the Pacific, were once there were no quadrupeds and no domestic fowls, hogs are now wild in their forests, and domestic fowls are abundant. The first pairs were left on the Islands by Captain Cook in 1772.

Thus changes of great magnitude and of great importance in the physical geography of the globe have been effected by man. The intelligence, the spiritual energy that is in man, has prompted him to attempt, and persevere through a long succession of ages in the attempt, to secure the conquest of

• Dr. Carpenter's "Comparative Physiology," p. 624. + Ibid., p. 623.

nature. While the lower animals are every where the unresisting slaves of nature, the mere sport of their destiny, or of the lot. which external conditions impose upon them, without making any efforts to modify the circumstances around them, man, on the contrary, gains victories over nature. Hence it is that he is a cosmopolitan. While among the wild animals of the forest each species can exist only on a comparatively small portion of the earth's surface, man is capable of living in every clime, of modifying the circumstances around him, and carrying along with him over their natural geographical boundaries those plants and animals which are needful for his convenience. or his food.*

II. The influence of mind on the physiognomy of the earth.

We are here employing the term "physiognomy" in a special sense, to denote the aspect which the earth presents at any spot within the ordinary range of vision, as distinct from the more comprehensive vision of science.

The earth, like the human countenance, has an expression, There is upon it the wild and untamed luxuriance of nature, or the softness and elegance of culture. Now its countenance is gloomy, savage, terrific. Now it is mild, ethereal, lovely. This face and aspect of nature has been wonderfully changed by the skill and art of man. Her features have been softened and molded by cultivation. The lineaments of her countenance have been altered by the hand and device of man.

but

Imagine the aspect which Great Britain presented to the eye of the Roman invader, as contrasted with the face it now presents to the eye of the modern traveler. True, the general contour, the outlines of the coast, and the lines of mountain ranges, are the same as they were two thousand years ago; the physiognomy of the country is so changed that, were Julius Cæsar to return, he could not recognize one foot of the territory of ancient Albion. England was then covered with dense primeval forests, in which painted savages followed the chase. There were no houses, no roads, no cultivated fields, no populous cities. Her shores were, to the polished Romans, the object of mysterious dread, like that with which the Ionians, in the

* See "Agassiz and Gould's Zoology," p. 133.

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