petually flying off. Yet nothing is eternal or immutable but these elementary seeds or atoms themselves. The compound forms of matter are continually decomposing and dissolving into their original corpuscles; to this there is no exception: minerals, vegetables, and animals, in this respect all alike, when they lose their present make, perishing for ever, and new combinations proceeding from the matter into which they dissolve. But the world itself is a compound though not an organized being; sustained and nourished, like organized beings, from the material pabulum that floats through the void of infinity. The world itself must, therefore, in the same manner, perish: it had a beginning, and it will have an end. Its present crasis will be decompounded; it will return to its original, its elementary atoms; and new worlds will arise from its destruction.

Space is infinite, material atoms are infinite, but the world is not infinite. This, then, is not the only world, nor the only material system that exists. The cause that has produced this visible system is competent to produce others: it has been acting perpetually from all eternity; and there are other worlds, and other systems of worlds, existing around

us.

Those who are acquainted with the writings of Sir Isaac Newton and Mr. Locke, will perceive in this sketch of the Atomic philosophy the rudiments of a very great part of their own systems, so far as relates to physics; we may, indeed, fairly regard them as offsets from the theory before us, cleared in a very great degree of its errors, and enlarged in their principles, and fortified by more recent ob

servations and discoveries. I must, for the present, confine myself to the following quotations from the first of these high ornaments of our country. "All things considered," says Sir Isaac," it seems probable that God, in the beginning, formed matter in solid, massy, hard, impenetrable, moveable particles; of such sizes and figures, and with such other properties, and in such proportion to space as most conduced to the end for which he formed them." So again : "While the primitive and solid particles of matter continue entire, they may compose bodies of one and the same nature and texture in all ages: but should they wear away, or break in pieces, the nature of things depending on them would be changed. Water and earth, composed of old worn particles and fragments of particles, would not be of the same nature and texture now, with water and earth composed of entire particles at the beginning; and therefore, that nature may be lasting, the changes of corporeal things are to be placed only in the various separations, and new associations and motions of these permanent particles: compound bodies being apt to break, not in the midst of solid particles, but where those particles are laid together, and touch only in a few points."

The Epicurean doctrine, moreover, of a flux and reflux of elementary particles exterior to every material system, perpetually feeding and replenishing it, and carrying off its dissolved and rejected rudiments, bears no small resemblance to the ethereal medium of Sir Isaac Newton; and, in its law of action, has been singularly revived by Professor Leslie, in his principles of impulsion, as detailed in his "Inquiry into the Nature of Heat." It is a

doctrine, also, peculiarly coincident with Herschel's recent theory of nebulæ, or milky ways in the heavens, which, contrary to his own earlier opinions, and those of former astronomers, who ascribed such appearance to the mixed light thrown forth from clusters of stars too remote to be reached by the best telescopes, he now resolves, as we shall have occasion to show more minutely in due time, into masses of a luminous fluid, existing independently of all stars or planets, though originally, perhaps, emitted from them; aggregated by a variety of causes that tend to give its minute particles unity; sometimes forming new stars by its condensation, and often feeding and regenerating those that are exhausted.

Such is a brief survey of the chief theories of the primitive or elementary substance of matter which have been offered in ancient or modern times; from a combination of the different particles of which, in different modes and proportions, and under the operation of different laws, all sensible bodies are supposed to have proceeded.

Of sensible bodies thus produced, some, however, in direct repugnancy to the Atomic philosophy, whether of ancient or more recent times, have been very generally conceived to have been formed first; to be peculiarly simple in their composition, indecomposable by any known powers in their structure, and to be the basis of all other bodies, or those from which all other bodies proceed, by different unions and modifications: and hence such substances have been denominated constituent principles, or constituent elements; concerning the kind and number of which, we have had almost as many opinions offered as

concerning the origin and nature of the primitive principles themselves.

Thus, among both the ancients and the moderns, sometimes fire, sometimes air, sometimes earth, and sometimes water, has been considered as the sole constituent element or source of things. Sometimes two of these substances have been thus denominated, and sometimes three; but more generally the whole. Occasionally, indeed, a fifth and even a sixth have been added to the number, as cold and oil, each of these having at times been considered as simple and indecomposable substances: while, under the old Atomic system, and especially as improved by Epicurus, all such principles were completely swept away, and no one sensible substance whatever was conceived to be better entitled to the character of a constituent principle than another; the whole equally flowing from peculiar modifications and combinations of the primitive or elementary principles the RERUM PRIMORDIA and equally re

solving into them upon decomposition.

Of these different theories, the greater number are scarcely worth examining; and I shall only therefore observe, that for that which supposes the existence of four distinct elements, fire, air, earth, and water, and which for ages has been in almost universal acceptation, and would have been so still but for the recent discoveries of chemistry, we are indebted to Empedocles. This celebrated philosopher, and excellent poet, flourished about four centuries before the Christian æra. His opinions, like those of almost all the earliest sages, were given in metre, in a didactic poem, "ON NATURE," of which only a few fragments have descended to our

own times. He was a native of Sicily, and his talents and his country are celebrated by Lucretius, who was nevertheless of a very different school of philosophy, in verses so elegant and so descriptive, that I cannot refrain from presenting you with a literal but very humble translation of them; introduced, more especially, as they are, with observations upon different rival philosophers, who employed one, two, and various other numbers of the commonly esteemed elements, and in various combinations, as the basis of their respective theories.

Nor wanders less the sage who AIR with FIRE
Would fain commix, or limpid STREAM With EARTH;
Or those the whole who join, FIRE, ETHER, EARTH,
And pregnant SHOWERS, and thence the world deduce.
Thus sung EMPEDOCLES, in honest fame

First of his sect; whom AGRIGENTUM bore
In cloud-capt SICILY. Its sinuous shores
Th' IONIAN main, with hoarse unwearied wave,
Surrounds, and sprinkles with its briny dew:
And, from the fair Æolian fields, divides
With narrow frith that spurns th' impetuous surge.
Here vast CHARYBDIS raves: here ETNA rears
His infant thunders, his dread jaws unlocks,
And heaven and earth with fiery ruin threats.
Here many a wonder, many a scene sublime,
As on he journeys, checks the traveller's steps;
And shows, at once, a land in harvests rich,
And rich in sages of illustrious fame.
But nought so wond'rous, so illustrious nought,
So fair, so pure, so lovely can it boast,
EMPEDOCLES, as thou! whose song divine,
By all rehearsed, so clears each mystic lore,
That scarce mankind believed thee born of man.
Yet e'en EMPEDOCLES, and those above

Already sung, of far inferior fame,

Though doctrines frequent from their bosoms flow'd