STUDY OF NATURAL HISTORY.

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rately between two different animals or plants which were before wrongly confounded together; but to plume oneself on having picked up, for the first time, a shell or a sea-weed, which any one visiting the same ground might have equally done, is simply childish.

I speak now of that improper egotism which takes almost as much credit to itself as if it were the author of what it has found. I am very far from condemning the pure-minded joy, one of the most delightful feelings of a naturalist, which springs freely in his heart, and glistens in his eye, when first it rests upon an unknown object. This feeling is a mixture of warm affections which cannot confine themselves to a single breast, but instantly seek for sympathy. The first impulse is, to exhibit the novelty to another that he may share our delight, and that we may see him do so. And if there be none to sympathise, how naturally the grateful heart looks up and worships the Author of its enjoyment! Cold as the heart's feelings may be at other times, the fervour of the moment awakens all its better nature. This enjoyment may seem a small thing to call forth gratitude, when we are accustomed to receive so many blessings at the hand of God in a thankless or indifferent spirit. These blessings we seem to look on as our birthright, as members of His family; but the discovery of a new object among the works of creation acts like a special revelation, however small, to ourselves as individuals, and this feeling of individuality touches a chord in the human breast which is ever ready to vibrate. The man whose life is saved by what appears to be a special interference of Providence in his favour

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STUDY OF NATURAL HISTORY.

feels strongly what all ought to feel who know that at every moment of our lives the same care is exercised upon us. But the care in the one case is for the general good, the interest of which often calls for individual suffering; in the other, the welfare of the individual seems the special object of providential forethought. The latter brings God as it were personally before us. He is no longer merely the Creator exercising oversight over a vast dominion, but he is our Preserver, protecting us in our going forth and coming in. Similar, though weaker, are the feelings called forth by a closer insight into Nature, and a more intimate acquaintance with her works. When we begin the study, our conception of the Author of Nature may be diffuse— a vague idea as of some illimitable Power, in ceaseless action; but the more we pursue this delightful study, the more we recognise, if we work in a proper spirit, proofs of the personality of God. Though now we can know Him but in part, and only see Him reflected in his works as it were "through a glass darkly," we look forward to a time when we shall behold Him "face to face," and shall know Him, even as we ourselves are known."

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THE "World of Waters" is a hackneyed expression, often used in no more comprehensive sense than as signifying the Ocean, in contradistinction to the dry land. The waters of the ocean do, indeed, spread over the greater part of the globe, the proportion of sea compared to land being nearly as three to one; but the "World of Waters" embraces much more than the oceanic basins. A moment's consideration will show that we may include under this name perhaps every portion of the surface of the globe, and certainly every portion which is the abode of living things, whether plants or animals. The "World of Waters" thus be

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THE OCEAN THE FOUNTAIN OF WATERS.

comes co-extensive with the organic world or world of life; for every plant that grows and every animal that breathes is absolutely dependent on water for its life. If the air did not contain water in solution, the vegetable world would quickly become a vast Hortus Siccus, and the animal world be converted into a mummy museum.

Such a state of things would involve the destruction of animated nature, and this result is averted only through the agency of water. The great reservoir of this life-sustaining agent is the ocean, which is at once the fountain whence the waters flow, and the goal to which they return and where they centre. "All the rivers," says the Wise Man, "run into the sea, yet the sea is not full; unto the place from whence the rivers come, thither they return again." This circulation of the waters is brought about in a very simple manner, by the influence of the sun, alternately raising and lowering the temperature of the air. Under an increased temperature vapour rises rapidly from any exposed surface of water, and is greedily absorbed by the air, in which it is either perfectly dissolved, when it becomes invisible, or is partially condensed in cloud or fog. A cloudless sky is no proof of the absence of watery vapour in the air, for warm air will hold in perfect solution a very considerable weight of vapour. A reduction of the temperature causes the condensation of the vapour, which is returned to the earth as cloud, fog, dew, or rain. The force of gravity compels the condensed water to seek a lower level, it collects in rills, streams, rivers,-which in most cases flow towards

SALT WATER AND FRESH.

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the ocean, whose vapours have fed them at the source. Thus a circulation, indispensable to the welfare of plants and animals, is maintained over the surface of the globe, either on the earth or through the air.

There is a marked difference, however, between the water which fertilises the earth and air, and that which remains in the great body of the Ocean. Sea-water, as every one knows, is salt, while what falls from the atmosphere, and supplies springs and rivers, is destitute of saltness, or fresh. When evaporation of sea-water takes place, the salts dissolved in the sea do not rise in the vapour, but remain behind;-and were the process continued a sufficient length of time, and were no fresh water introduced by rivers, the salts would accumulate in the waters of the ocean to such a degree that they would at last be deposited in a solid form at the bottom. There would take place, on a vast scale, what occurs in the common method of procuring salt from sea-water, in hot countries, where the water is exposed to the sun in shallow pans until nothing remains but a crust of salt. This does not happen to the Ocean, solely because the amount of fresh water which continually returns into it, compensates for what had been withdrawn; and if there be any deficiency it is of so small an amount as to cause a change in the constitution of the ocean only in a very extended course We have no evidence to show that any such change has occurred during the historic period; but it is reasonable to think that the change which we know, from the fossil remains of an earlier creation, has come over the marine fauna, may have been connected with

of ages.