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we pass our hand rapidly through it we find resistance; and we are certain that it is fluid, its particles are easily displaced, and yield to all kinds of impressions. Were it solid, we could neither inspire it, nor move in it with facility. It possesses weight in common with other bodies, being about 816 times lighter than water *. The force with which the air weighs upon every square foot of the earth is equal to a weight of 2160 pounds. And a man, whose surface is about fourteen square feet, sustains a weight of atmospheric air equal to 30,240 pounds. This may appear incredible; but the resistance of the air contained in our lungs prevents our suffering any inconvenience from the pressure of the external air, an equilibrium being thus preserved.

The elasticity of the air is equally certain; it is continually making an effort to fill a greater space, and, though capable of compression, as soon as the pressure is removed, it again expands. This is suf ficiently proved by means of heat, which rarefies it to such a degree, that it may be made to occupy five or six hundred times more space than it did before the heat was applied, without losing its elastic power. All these phenomena are highly worthy of admiration, and in them we may perceive the causes of many astonishing effects. It is in the air that our globe is suspended; and it is in the air also that the clouds are collected, forming so many beautiful shades and colours, and which, as they are rarefied or condensed, suspend the vapours, or permit them to descend on the earth, in rain, hail, or snow. Without air life cannot be supported, nor fire and water exist.

Thus then the air also announces the grandeur,

*Its specific gravity, according to the experiment of sir George Shuckburgh, when the barometer is at 30 inches, and the thermometer between 50 and 60 degrees, is 0.0012. One hundred cubic inches of air weigh 31 grains troy.-Thomson's Chemistry.

power, and goodness of God, whose infinite wisdom alone could adapt this element to so many and various purposes. God creates and governs the rain, the snow, the winds, the thunder, and the lightning; he measures the quantity, gravity, elasticity, and motion of the air, and mercifully causes it to serve our necessities, and contribute to the general welfare of our globe. Let us then, who every moment breathe this air which supports our lives, adore the depths of the riches of His marvellous wisdom and understanding, who alone has created all these things manifested in the whole economy of nature with infinite splendor!

MARCH XXIV.

Nothing new under the Sun.

WITH respect to man, no doubt, there are many new things which take place in the earth; in every season we see new flowers spring up, new fruits ripen, and the whole face of nature annually changes. Every day is productive of new events and new revolutions; the situation of objects is continually changing, or they present themselves to our senses under different forms. It is only relatively to the limited extent of our knowledge and understanding that there is any thing new under the sun; and in this light nothing is more true than the saying of Solomon, "What has been will be, and what has been done will be done, and there is nothing new under the sun." God has not thought fit to multiply things unnecessarily; there is every thing which can satisfy our wants, gratify our desires, and satiate our curiosity. Far from exhausting, we are scarcely able to acquire a superficial acquaintance with the works of the Creator; our senses are not sufficiently acute and powerful to perceive all

the works of nature, and our understanding is too weak to comprehend them; so that we can never form a just and accurate idea of the creation, nor of every created being: hence we often believe many things are new under the sun which are only new to ourselves. As the empire of nature is immense, and as we can grasp only a very small part at one view, we suppose every thing we see for the first time to be new; because in every part of the world there is an infinite variety of appearance, and diversity of imagery.

Nature does not require a continued and endless creation; it is sufficient that the Supreme Being preserves the order which he established in the beginning. There is no necessity for a number of springs to vary the works already produced; for they succeed each other, and return in regular order, and yet appear so infinitely diversified as to seem always new. The impossibility of our numbering or conceiving the whole extent of the works of nature, whilst it convinces us of the weakness of our capacity, strongly proves the existence of one great First Cause of all, an Almighty God.

But are there not many recent discoveries, entirely unknown to the ancients? Are we not now familiar with phenomena in the kingdom of nature, of which we formerly had no idea? Most of these discoveries. have proceeded rather from the stimulus of want, than that of arriving at truth. As our wants multiply, new means are necessary to supply them; but these existed. long before we knew them. Minerals, vegetables, and animals, that have lately been discovered, already existed in the earth, or upon its surface, long before the researches of men brought them to light; and many that we imagine to be modern discoveries were very probably known to the ancients.

Were the world (what from the nature of things is impossible) the work of chance, the same fortuitous

agent that caused its first existence might operate today as well as then; and we should be continually witnessing new productions. But the world and all created things being formed by a perfect Being, every thing that is made bears the stamp and broad impression of an all-powerful God, which established the foundations of the earth with wisdom, and formed in the beginning every thing that was essential to the preservation and well-being of the whole; so that there is no necessity for a new creation, or new laws, but all moves in harmony, guided by eternal sapience. In all, and through all, God is magnified and glorified; and to him is due eternal honour and everlasting praise.

MARCH XXV.

Of Caves found in Mountains.

CAVES are generally found in mountains, and very seldom in plains. They are frequently caused by the eruptions of volcanoes, and the explosions of earthquakes. But what end do such chasms answer? Though we could discover no certain end in their existence, we may take for granted that they are not formed in vain.

However, the purposes they answer are often evident; they serve as reservoirs for water, which may be had recourse to upon a deficiency of rain. They are also useful for the freer circulation of air through the earth, by more readily permitting its ingress and egress, and thus lessen the frequency of earthquakes. They sometimes fill with water, and form lakes; such is the lake Zirchnitzer, in Carniola, which fills in June, and loses its waters among the neighbouring mountains in September. It is sometimes navigable,

and at others so dry, that the inhabitants may plough, sow, reap, and hunt in it. Another use of caves is the shelter and retreat which, during winter, they offer to animals. Hence we find more cause to admire the wisdom and bounty of God; and the deeper our researches penetrate into nature, the less shall we find of useless matter, and the greater reason we shall have to adore the sublimity and perfections of God in his works.

MARCH XXVI.

Circulation of Sap in Trees.

THE trees, which during several months appeared entirely dead, begin gradually to revive, and in the space of a few weeks will give much more evident signs of vitality; the buds will sprout, open, and the sweet blossoms expand. Though we have observed this revolution at the commencement of several successive springs, we have perhaps been ignorant of the means conducing to this end. The effects which we perceive in spring to take place in trees and other vegetables are caused by the circulation of the sap, which begins to move in the vessels containing it when acted upon by a milder air and increase of warmth. As the life of animals depends upon the circulation of blood, so does the life and growth of plants depend on the circulation of the sap, which is to them what blood is to animals. To effect this, nature has formed and adapted all parts of vegetables to concur in the preparation, motion, and conservation of this nourishing juice.

It is principally by the bark that the sap, in the spring, begins to ascend from the roots into the body of the tree, and that even throughout the year life

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