by an ancient prophet, that remained to be fulfilled. The vision, and the prophecy, are now sealed. The Mosaic dispensation is closed; and he bowed his head, and gave up the ghost. It is finished.' When he uttered these words, he changed the state of the universe. At that moment the law ceased, and the Gospel commenced. This was the ever memorable time which separated the old and the new world from each other. On one side of the point of separation, you behold the law with its priests, its sacrifices, and its rites, retiring from sight; on the other side, you behold the Gospel, with its simple and venerable institutions, coming forward into view. Significantly was the veil of the temple rent in this hour; for the glory then departed from between the cherubims: The legal high Priest delivered up his urim, and Thummim, his breast-plate, his robes, and his incense; and Christ stood forth as the great high Priest, of all succeeding generations. By that one sacrifice which he now offered, he abolished sacrifices for ever. Altars on which the fire had blazed, for ages, were now to smoke Victims were no more to bleed. Not with the blood of bulls, and goats, but with his own blood, he now entered into the holy place, there to appear, in the presence of God, for us. This was the hour of association and union, to all the worshippers of God. When Christ said, it is finished, he threw down the wall of partition which had so long divided the Gentile from the Jew. He gathered into one, all the faithful, out of every kindred and people. He proclaimed the

no more.

hour to be come, when the knowledge of the true God, should be no longer confined to one nation, nor his worship to one temple, but over all the earth, the worshippers of the Father, should serve him in spirit, and in truth. From that hour, they who dwelt in the uttermost parts of the earth, strangers to the covenant of promise, began to be brought nigh. In that hour the light of the Gospel dawned from afar on the British Islands. Blair.

CHEMICAL COMPOSITION OF THE ATMOSPHERE.

The heads of an interesting Lecture on the Chemical Composition of the Atmosphere, as delivered by Mr. Sweetlove, at one of our public Institutions, on the 4th of the 6th month, 1833.

THE importance of the chemical properties of the atmosphere is evident, when we for a moment consider its extensive relations in the grand field of nature's operations: besides being the food of common fire, air is constantly necessary to the existence of animal and vegetable life; neither animals nor fishes, trees nor plants, could survive its privation. Every living being possesses an apparatus, by which the atmosphere operates in an important manner upon its structure. The great mass of air which surrounds our globe is the unnoticed cause of innumerable familiar effects in nature. Composition and destruction form a circle of varied existence every where around us. One thing perishes only to supply materials for another, which in its turn passes away. Earth and air, form the veget

able, which changes to the animal; and both are again changed, through the medium of atmospheric influence, into organic. In the spring, when the air is warm and moist, the landscape smiles with awakening life; as the summer heats the air, it ripens fruit; and, with the decaying fire of autumn, the leaves gently melt into dissolution. What is poetically termed the "tooth of time," which sooner or later destroys the proudest and the noblest, as well as the most insignificant works of human ingenuity, which eats away

"The cloud-capp'd towers, the gorgeous palaces,

The solemn temples,"

is but the silent operation of the atmsophere. For many ages, air was conceived to be a simple element. Ancient philosophers made it one of the four, of which they supposed all things were constituted. Such of its effects as commonly manifested themselves, were attributed to its heat or cold, its moisture or dryness; and those which could not be explained in this way were reckoned to be supernatural, and the immediate effect of Divine agency. At a period anterior to this, when men did not even reason so far as to give causes to effects in external nature, but exercised their imagination to personify its principles, the air was adored under the names of Jupiter and Juno, the former representing the superior and supposed nobler parts of the atmosphere, and the latter the inferior or grosser parts or portion. Homer in his Iliad gives, in a beautiful allegory, the loves of Jupiter and Juno, in whose names he personified the æther, or heaven, and the

lower air or clouds; and he ascribes the fruitfulness of spring to the genial weather which results from the smiles of the heathen deity upon his mistress. Virgil, also, poetically embodies the same allegory, in his second Georgic; and it affords Milton a fine comparison, to express the fondness with which Adam beheld the loveliness of Eve, where he says,

"He in delight,

Both of her beauty and submissive charms,
Smil'd with superior love, as Jupiter

On Juno smiles, when he impregns the clouds
That shed May flowers."

And this last expression, "of clouds shedding flowers," illustrates the fine one in the Psalms, of the "clouds dropping fatness."

After this eloquent introduction, the lecturer proceeded to consider one of the most important substances in nature, called oxygen, and a variety of instances of the extent and energy of its chemical affinities were adduced.

The intense energy with which oxygen unites to substances was shown by the vivid combustion of sulphur in oxygen gas; and vigour of its chemical action was illustrated by a lighted taper being applied to the mouth of a glass bottle, containing a mixture of oxygen and hydrogen gases, and causing a loud explosion. The energy of oxygen was also beautifully proved by a bit of sodium, or potassium, bursting into flame when it was thrown upon cold water. It is in considering the vivid energy of oxygen, that the admirable wisdom of Providence becomes apparent, in

diluting that powerful agent with a sufficient portion of inert nitrogen, to constitute our atmosphere, and render it suitable for the various useful purposes which it fulfils.

In pure oxygen, animals seem at first excited, but soon languish, and in a short time die from exhaustion. A small taper with a red snuff, was inserted in a vessel containing some of this gas, and immediately it burst into a beautiful flame, and burned with much greater brilliancy than in common air, from which it might be inferred, said the lecturer, that if our atmosphere consisted only of this powerful agent, the world must inevitably be destroyed by fire, a single spark would give birth to an universal conflagration.

It is a remarkable fact, that at all times, and in all places, the quantity of oxygen, in a given portion of the atmospheric air, is constantly the same. In whatever season, or whatever climate, whether in spring, summer, autumn, or winter,--whether taken from the polar regions, or from the torrid zone,-whether from the summits of the loftiest mountains, or from the surface of the lowest sands,-whether from the greatest altitude that æronauts have ever soared, or from the lowest depths to which miners have penetrated,— whether from the most fertile and highly cultivated countries, or from the most barren deserts,- whether from the surface of the ocean, hundreds of miles from land, or from the interior parts of the most extensive continents, the gases composing atmospheric air, have never been found to vary in their proportions.