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EARTH, AIR, AND SEA.
"He measured the waters in the hollow of his hand
THE mean annual fall of rain on the entire surface of the earth is estimated at about five feet. To evaporate water enough annually from the ocean to cover the earth, on the average, five feet deep with rain; to transport it from one zone to another; and to precipitate it in the right places, at suitable times, and in the proportions due, is one of the offices of the grand atmospherical machine. All this evaporation, however, does not take place from the sea, for the water that falls on the land is re-evaporated from the land again and again. But in the first instance it is evaporated principally from the torrid zone. Supposing it all to be evaporated thence, we shall have, encircling the earth, a belt of ocean three thousand miles in breadth, from which this atmosphere hoists up a layer of water annually sixteen feet in depth. And to hoist up as high as the clouds, and lower down again all the water in a lake sixteen feet deep, and three thousand miles broad, and twenty-four thousand long, is the yearly business of this invisible machinery. What a powerful engine is the atmosphere! and how nicely adjusted must be all the cogs, and wheels, and springs, and compensations of this exquisite piece of machinery, that it never wears out nor breaks down, nor fails to do its work at the right time and in the right way!....
We now begin to perceive why it is that the proportions between the land and water were made as we find them in nature. If there had been more water and less land, we should have had more rain, and vice versa; and then climates would have been different from what they are now, and the inhabitants would not have been as they are, neither animal nor vegetable. And as they are, that wise Being who, in his kind providence, so watches over and regards the things of this world that he takes note of the sparrow's fall, and numbers the very hairs of our head, doubt
less designed them to be. The mind is delighted, and the imagination charmed, by contemplating the physical arrangements of the earth from such points of view as this is which we now have before us. From it the sea, and the air, and the land, appear each as a part of that grand machinery upon which the well-being of all the inhabitants of earth, sea, and air depends; and which, in the beautiful adaptations that we are endeavouring to point out, affords new and striking evidence that they all have their origin in ONE omniscient idea, just as the different parts of a watch may be considered to have been constructed and arranged according to one human design.
In some parts of the earth the precipitation is greater than the evaporation: thus the amount of water borne down by every river that runs into the sea may be considered as the excess of the precipitation over the evaporation that takes place in the valley drained by that river. In other parts of the earth the evaporation and precipitation are exactly equal, as in those inland basins such as that in which the city of Mexico, Lake Titicaca, the Caspian Sea, &c., &c., are situated; which basins have no ocean drainage. If more rain fell in the valley of the Caspian Sea than is evaporated from it, that sea would finally get full and overflow the whole of that great basin. If less fell than is evaporated from it again, then that sea, in the course of time, would dry up, and plants and animals there would all perish for the want of water. In the sheets of water which we find distributed over that and every other inhabitable inland basin, we see reservoirs or evaporating surfaces just sufficient for the supply of that degree of moisture which is best adapted to the well-being of the plants and animals that people such basins. In other parts of the earth still, we find places, as the Desert of Sahara, in which neither evaporation nor precipitation takes place, and in which we find neither plant nor animal to fit the land for man's use.
In contemplating the system of terrestrial adaptations, these researches teach one to regard the mountain ranges and the great deserts of the earth as the astronomer does the counterpoises to his telescope;-though they be mere dead weights, they are, never
theless, necessary to make the balance complete, the adjustment of his machine perfect. These counterpoises give ease to the motions, stability to the performance, and accuracy to the workings of the instrument. They are "compensations." Whenever I turn to contemplate the works of nature, I am struck with the admirable system of compensation-with the beauty and nicety with which every department is adjusted, adapted, and regulated according to the others. Things and principles are meted out in directions apparently the most opposite, but in proportions so exactly balanced, that results the most harmonious are produced.
It is by the action of opposite and compensating forces that the earth is kept in its orbit, and the stars are held suspended in the azure vault of heaven; and these forces are so exquisitely adjusted, that, at the end of a thousand years, the earth, the sun, and moon, and every star in the firmament, is found to come and twinkle in its proper place at the proper moment! Nay, philosophy teaches us that when the little snowdrop, which in our garden walks we see raising its head at "the singing of birds," to remind us that "the winter is past and gone," was created, the whole mass of the earth, from pole to pole, and from circumference to centre, must have been taken into account and weighed, in order that the proper degree of strength might be given to its tiny fibres ! Botanists tell us that the constitution of this plant is such as to require that, at a certain stage of its growth, the stalk should bend, and the flower should bow its head, that an operation may take place which is necessary in order that the herb may produce seed after its kind; and that, after this fecundation, its vegetable health requires that it should lift its head again and stand erect. Now, if the mass of the earth had been greater or less, the force of gravity would have been different: in that case, the strength of fibre in the snowdrop, as it is, would have been too much, or too little ;—the plant could not have bowed or raised its head at the right time; fecundation could not have taken place; and its family would have become extinct with the first individual that was planted, because its "seed" would not have been "in itself,"
and therefore could not have reproduced itself; and its creation would have been a failure.
Now, if we see such a perfect adaptation, such exquisite adjustment, in the case of one of the smallest flowers of the field, how much more may we not expect "compensation" in the atmosphere and the ocean, upon the right adjustment and due performance of which depends not only the life of that plant, but the well-being of every individual that is found in the entire vegetable and animal kingdoms of the world!..... Therefore, in considering the general laws which govern the physical agents of the universe, and which regulate them in the due performance of their offices, I have felt myself constrained to set out with the assumption, that if the atmosphere had had a greater or less capacity for moisture, or if the proportion of land and water had been different —if the earth, air, and water had not been in exact counterpoisethe whole arrangement of the animal and vegetable kingdoms would have varied from their present state. But God, for reasons which man may never know, chose to make those kingdoms what they are. For this purpose it was necessary, in his judgment, to establish the proportions between the land and the water, and the desert, just as they are; and to make the capacity of the air to circulate heat and moisture just what it is, and to have it to do all its work in obedience to law and in subservience to order.
If it were not so, why was power, given to the winds to lift up and transport moisture, and to feed the plants with nourishment? or why was the property given to the sea, by which its waters may become first vapour, and then fruitful showers or gentle dews? If the proportions and properties of land, sea, and air were not adjusted according to the reciprocal capacities of all to perform the functions required of each, why should we be told that HE "measured the waters in the hollow of his hand, and comprehended the dust in a measure, and weighed the mountains in scales, and the hills in a balance?" Why did he span the heavens, but that he might mete out the atmosphere in exact proportion to all the rest, and impart to it those properties and powers which it was
necessary for it to have, in order that it might perform all those offices and duties for which he designed it?
Harmonious in their action, the air and sea are obedient to law and subject to order in all their movements. When we consult them in the performance of their manifold and marvellous offices, they teach us lessons concerning the wonders of the deep, the mysteries of the sky, the greatness, and the wisdom, and the goodness of the Creator, which make us wiser and better men. The investigations into the broad-spreading circle of phenomena connected with the winds of heaven and the waves of the sea are second to none, for the good which they do and for the lessons which they teach. The astronomer is said to see the hand of God in the sky; but does not the right-minded mariner, who looks aloft as he ponders over these things, hear His voice in every wave of the sea that "claps its hands," and feel His presence in every breeze that blows ?
LAND AND SEA BREEZES.
THE inhabitants of the sea-shore in tropical countries wait every morning with impatience for the coming of the sea breeze. It usually sets in about ten o'clock. Then the sultry heat of the oppressive morning is dissipated, and there is a delightful freshness in the air, which seems to give new life to all for their daily labours. About sunset there is again another calm. The sea breeze is now done, and in a short time the land breeze sets in. This alternation of the land and sea breeze—a wind from the sea by day and from the land by night is so regular in inter-tropical countries, that it is looked for by the people with as much confidence as the rising and setting of the sun.
In extra-tropical countries, especially those on the polar side of the trade-winds, this phenomenon is presented only in summer and autumn, when the heat of the sun is sufficiently intense to produce the requisite degree of atmospherical rarefaction over the land.