world unto himself, and not imputing unto men their trespasses.

I say nothing at present of the unhappy state of those who go down to the grave without hope. They are in the hand of God; and it is not for mortal man to withdraw the veil in which this awful subject is involved. Doubtless the Judge of all the earth does right; but there are some things connected with the existence of evil which seem destined not to be revealed on this side of the grave. To our awakened sight the light poured on these mysteries, we may well believe, will form a theme for new admiration and praise throughout the ages of eternity.

Meanwhile, let us take comfort in the declarations of the revealed word. These promises are to us and to our children. This is not the history of God's dealings with another world, but with the world in which we live ; it is not an account of grace and mercy to another guilty race, but to the very race to which we belong; nor is it to other individuals of that race only that these inestimable blessings are offered, but to ourselves. If we will accept of the offered salvation, we are included in that history-the objects of that grace and mercy-the partakers of these inestimable blessings. What manner of persons then ought we to be?

TWELFTH WEEK-THURSDAY.

MAN. PHYSICAL EFFECTS OF CLIMATE.

THAT the whole human race is originally derived from a common parent, must be admitted by all who acknowledge the authority of Scripture, although there have been some daring speculators, who, not more contrary to the dictates of Revelation, than sound philosophy, have attempted to maintain an opposite opinion. Whence,

then, the varieties of the human race, so remarkable, especially in three great branches, distinguished by their colour into the fair, the yellow, and the black; or, by their aboriginal habitation, into the Caucasian, the Mangolian, and the Ethiopian tribes?

This question cannot be answered satisfactorily in a few words. Nevertheless, there are some well known facts, the mere mention of which may serve to allay the surprise which may at first be excited by the contemplation of these varieties, and may tend to show how consistent such variations are with the physical laws which pervade organized existence. The changes which are naturally effected by cultivation, in the appearance and qualities both of the plants and animals which have been subjected to the influence of man; the effect which a peculiar quality or conformation accidentally occurring in the parent produces in the offspring, frequently observable for many generations; and especially the influence of food and climate on the physical constitution, seem of themselves quite sufficient to account for the remarkable varieties which the human frame exhibits in its different branches. It is to the latter effect that I intend at present to confine my attention.

One remarkable effect of climate is to darken the skin. That this results from the heat of the intense rays of the sun, may be fairly inferred, not only from the fact that we find the inhabitants of the tropics, without exception, of a complexion more or less dark, but also from another, and perhaps a more convincing fact, that the descendants of Europeans, when transported to the equatorial regions, assume the black tint after the lapse of some generations. This is strikingly exemplified in the case of a colony of Jews, discovered in the Indian peninsula. Now, that this is a wise provision, we might safely conclude, from what we know of the provisions and accommodations of nature in other cases: But the philosophical principle can be assigned. It is true that a black colour, as I have elsewhere observed, absorbs the heat

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more readily than a white; and, therefore, if this were the only thing to be attended to, one would expect the complexion of the human body to be reversed in its locality, the purest white being found where the rays of the sun were most powerful, and the darkest in the regions verging towards the poles. But there is another principle which the progress of chemical science has very recently elicited, and which most satisfactorily accounts for the arrangement; it is this,—that a dark surface radiates heat much more readily than a surface of white. Now, the chief source of heat in a living body, is not the external atmosphere, or the rays of the sun, but the animal warmth, as it is called, that is, the heat generated inwardly by some hitherto obscure chemical process in the blood. It is of more importance to the comfort and health of the frame, that this internal source of temperature should be properly regulated, than that which is external ; and this is the provision which the wisdom of the Creator has actually adopted. In the colder regions, the fairness of the skin prevents the escape of the animal warmth; and, in the warmer, a dark colour is superinduced, that the same warmth may freely escape, thus compensating, in some degree, by this remarkable contrivance, for the differences in climate. The same principle operates, indeed, to a certain extent, even in temperate climates, where exposure to the summer's sun is well known to darken the complexion, an effect which the return of winter removes.

Another peculiarity induced by climate, is a difference in the freedom and extent of the perspiration, which serves also to modify the heat of the body. In the warmer climates, the pores are comparatively open, and the perspiration issuing freely, carries off from the frame the superabundant caloric, and at the same time bedews the body with a moisture which, in its evaporation, contributes not a little to create an agreeable coolness. But, besides this, there is a remarkable quality in the human body which enables it to resist the application of even

high degrees of heat. This has been proved by various interesting recent experiments; and it is on this principle, that some individuals have astonished the public by the exhibition of their power of existing in an oven, or an apartment, heated to such a considerable extent, as to roast the flesh which has been placed by their side. A similar power exists in the living frame, as regards cold; and, in both instances, habit produces an extraordinary accommodation on individuals long resident in a particular climate, and still more in their progeny after the lapse of some generations.

In another particular, there is an adaptation to heat of climate, of which St Pierre, alluding to the Negro race who inhabit Africa, the hottest region of the globe, thus writes:-"Nature has covered the head of those careless and unindustrious tribes with a fleece more crisp than a tissue of wool, which effectually shelters it from the burning heat of the sun. They are so perfectly sensible of its accommodation to this purpose, that they never employ a substitute head-dress; and there is no description of mankind among whom artificial coverings, as bonnets, turbans, hats, &c. are more rare than among the Negroes. They use such as are foreign to them, merely as objects of vanity and luxury; and I do not know of any one that is peculiar to their nation. The inhabitants of the peninsula of India are as black as they; but their turbans communicate to the hair, which, but for their head-dress, would perhaps be frizzled, the facility of growing and expanding."

But the chief physical effect produced by heat of climate, is that of relaxing the human frame, and making it less capable of exertion; and it is very remarkable, as an instance of accommodation to circumstances, that, where this unbracing effect is produced, nature is most liberal in her distribution of esculent plants and fruits; as if it were intended, by this profusion, to compensate for the want of energy in the human constitution.

Studies of Nature (Hunter's Translation), vol. ii. p. 4.

Hence also a moral effect is combined with what is purely physical, the nature of which will fall to be mentioned in the following paper.

TWELFTH WEEK-FRIDAY.

MAN. MORAL EFFECTS OF CLIMATE.

THAT some effects of a moral as well as of a physical nature, are produced on the human family, by differences of climate, can scarcely be doubted, though these effects are probably less marked than has frequently been alleged. That sloth, effeminacy, and a tendency to the excessive indulgences of sense, are more remarkably characteristic of the voluptuous regions of the tropics, than of those of sterner aspect, which verge towards the poles, is very generally admitted; and that this difference arises from causes partly physical, and partly mental, can scarcely be called in question.

It is not to be doubted, that a hot temperature of the atmosphere tends to enervate the human body; and it is possible, too, that a similar state of the climate may have some effect in exciting the passions, so far as these are of a physical nature ; but if this influence were as powerful as has been alleged, it would be much more uniform and permanent than history proves it to be. The abject Greeks and Romans of the present day, how utterly unlike are they to their predecessors of the ancient world! Yet the climate of these once classic regions, though there is reason to believe it has been in some respects altered by the progress of agricultural improvement in the adjoining continent, is not so different from its former state, as to make any important alteration in the physical state of the human body.

Moral effects, however, are not of so fixed and permanent a nature as physical; they depend on more numer