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is forever true-the knowledge of nature which is once perfect, may be forever useful.

When we approach to examine the fabric of nature, so far as it is subjected to our inspection, we find ourselves immediately placed amidst differing, if not contending powers. We perceive ourselves inhabitants of a globe, which science informs us, is but one of an immense system, surrounded by other forms, some similar to our own, some wandering over the earth, roaming in different elements, or confined to one; some, though located in one spot, varying in size and aspect with the passing seasons; or by other substances apparently composing portions of the globe itself, immoveable and changing not. The first impression which the mind receives, and that which most attracts the attention, is the wide difference that exists between the earth itself and the diversified forms which occupy its surface, between the silent, still and joyless repose of matter, and the noisy, gay and animated voice of life. The substances which compose that portion of the earth, whether crust, or covering or projecting masses of its mighty frame, which is alone submitted to our researches, are passive, immovable, insensible; those which inhabit that surface, are for the most part, active, capable of moving from place to place at pleasure, and possess great sensibility. The former have neither growth nor voluntary action, they have no mode of increase, but by the casual addition of similar particles, united by the strong and universal law of attraction. They can remain unaltered for indefinite periods of time; they have no death, but they perish or rather are destroyed solely by the separation of their component particles. The latter all increase in size through their own agency, by the constant addition of particles which they have the power to collect and assimilate to their substances by the principle of life; they perish whenever this addition and assimilation cannot be continued; and exist only for limited and indefinite periods. The former have no organization, are not produced by similar and pre-existent bodies, but are always and necessarily formed by the accidental contact of similar particles. They have no regular structure, but under certain circumstances, a modified attraction gives to each particle of matter a definite position, and generates the regular forms of crystallised bodies. The latter are all furnished with organs calculated and adapted to perform the functions of life, to collect, absorb and assimilate those particles which are necessary for their existence, and they always proceed from similar and pre-existing bodies.

VOL. II.-NO. 4.

53

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We may pursue still further these distinctions and these contrasts. Unorganised bodies, whether in massive forms or in scattered fragments, have still the inseparable qualities of matter, extension, form, impenetrability, vis inertiæ; they are subjected to those unalterable laws, and, apparently, to those alone which govern the material world; to that attraction which extends its influence and its activity from the centre of the earth, from the smallest atom on its surface to the interminable confines of space; to those laws of cohesion or chemical affinity which are but modifications of attraction; to motion, involuntary however and external-to expansion, to contraction, but still from foreign causes or external impulses; acted upon unceasingly, impassive in their own nature, obeying constantly definite and immutable laws. Unorganized matter is permanent and unchangeable, its particles may be separated or combined, but they are always the same. Though capable of modifications by combination, these combinations are only new aggregations of the same particles, and can be varied, reversed, destroyed. And the alterations which chemical combinations produce, are never counteracted by occult and inscrutable causes, like the influence of life in organized bodies.

Unorganized matter consists, therefore, as far as human observation can discover, of particles or molecules of a few distinct substances. These particles are independent and unalterable; combine them, mingle them, change the form, the proportions, the component particles of each combination, the elementary principles will be still unchanged, and may be again separated from all admixtures.

Organized bodies, besides the general properties of matter, possess a structure adapted to the functions of life. They are composed of fibres and tubes. They have parts sufficiently solid to develope and support their forms; fluids in constant motion or circulation to repair or preserve the solids. Their tissue is a species of net-work with the partitions more or less firm and compact, and the fluids pass along the cells or tubes, bearing foreign particles to every portion of the body, interposing new particles where nutriment or support is wanting, removing those that are superfluous or injurious-conveying to each different organ its peculiar secretions, to the surface those particles that pass off by exhalation. But while this motion appertains to the fluids, the impulse seems to be given by the contractile power of the solids, and this contractile power requires again in the solids both flexibility and the power of dilatation.

Such are the simple outlines of organization. Peculiar vessels or organs, receive in different modes, or by different laws, the

particles necessary to maintain the existence of each individual. These particles are either separated, in the first instance, as in vegetables, by the process of absorption, from those with which they are commingled, or being received, as in animals, in a peculiar sac or stomach, placed, generally, near the centre of each individual, the process of separation then takes place. In the former case, nothing seems to be introduced into the circulation but what is necessary for the support and the particular secretions of each individual; in the latter, provision is necessarily made to expel the superfluous residuum of the materials promiscuously collected. The particles separated for the maintenance of the individual, are driven by the muscular power of the solids, and mingle with the system generally, as we have already stated. In this action of the solids and fluids, in this continued motion, life may be said to consist, inseparably connected with organization.

In organized bodies there is always one plan, however each may be diversely modified, and every member bears a necessary relation to the whole. All unite to form one being, and the organs that may be accidentally severed have no separate existence.

In the scale of life, some of these organs appear to be more important than others; and in each individual, one or more may be considered as essential.

Death seems to be the inevitable condition and consequence of life. In unorganized bodies, where there is no necessary change, no alteration that is not accidental, forms may continue unaltered for indefinite periods, through a succession of ages.But, in organized bodies, a gradual but unceasing change continues through the whole period of their existence, and limits by its effects, their duration. At first, they increase in their dimensions to a certain and determinate extent, afterwards, in most parts of their frame, the addition of nutriment only adds to its solidity, and as this last process never ceases, the increasing density of the solids finally prevents the circulation of the fluids, and life terminates because its functions can no longer be performed.

Every thing thus seems to differ between these two classes, form, origin, termination, physical and even chemical properties. They have nothing in common, but the general properties of matter. Unorganized bodies are, essentially, homogeneous, each of their parts taken separately, affords the properties of the whole; while organized bodies are essentially heterogeneous, and their parts or organs differ from each other by their functions, their position, and their composition. Hence, it

follows, that in an unorganized body, where all the particles are alike, the position of each particle is unimportant; whilst, on the contrary, in bodies that are organized, where each organ has a structure peculiar to itself, the place of each particle is fixed and determined. Unorganized bodies, therefore, may be formed, and, in fact, are formed, by the simple contact and adhesion externally of particles similar to themselves. In organized bodies, on the contrary, each particle must be directed to that point with which it ought to assimilate. The increase in unorganized bodies is produced really by the simple and necessary effects of attraction, the most general property of matter; but this attraction cannot explain how, in bodies that are organized, each particle passes through spaces often very considerable, and by roads and passages sometimes very complex, before it is deposited upon the organ to which it peculiarly belongs.The particular force which produces this phenomenon is the vital power.

Such is the fundamental division of nature. It is the distinction between forms animate and inanimate; between bodies organized and unorganized, we might almost say, between life and death.

And when we engage in the study of these two great divisions, the system of animate and inanimate substances, we are guided in each by different principles, attracted by different sources of instruction and delight. In the one, we find every thing passive, inert and silent, but full of grandeur, and often unfolding scenes of awful and terrific sublimity; in the other, the joyous, active, and diversified spirit of life.

The one comprehends all of our researches into the nature of the earth, and the changes it has undergone, and into the composition and distribution of the inorganic masses which compose its surface-inquiries of high interest, and of almost unlimited extent-a science full of delightful, even if they have often proved visionary speculations-a pursuit peculiarly fascinating to those minds that delight to contemplate the vast, to admire the wonderful, to unravel the intricate, to trace the operations and results of immeasurable power. The mind feels elevated when surveying the magnificence of Divine Wisdom, it seems to partake of creative intelligence, when studying and unfolding its effects, its arrangements and its laws. When examining the earth, man looks not merely at its present state of existence, he strives to recall the march of ages, to transport himself to the birth-day of creation, to behold as from that day of wonder and of power, the gigantic fabric of this globe, formed, and moulded, and fashioned like clay in the potters lathe; in its

primæval order, beautiful and undisturbed, perfect in its symmetry-and the mighty frame, after it had received its form, abandoned apparently to desolation; left to the mingled influence of the most formidable elements; convulsed by fire, overwhelmed by water, shattered and disjointed by one power, decomposed and again consolidated by the other; the most compact rock mouldering under the united action of air, and rain, and frost; the softest paste indurated by fire, by pressure, or by cementing fluids; and this everlasting conflict of opposing principles, terminating in such harmonious, such felicitous results, as to adapt, perfectly, the surface of the earth to the beings who have been destined for its inhabitants.

In examining these results, in comprehending and illustrating these incidents, varied and magnificent as they may appear, we require no other agents than those which uniformly appertain to matter, no other principles than those which regulate and govern the material system.

But when from the inorganic and lifeless forms of nature, from the inert and passive substances which compose the surface of this globe; from the kingdoms of silence and repose, we pass to activity, to organization, and to life, we find inmediately other laws, other causes of action, other principles of association and of duration.

The power of creation is no where disclosed with so much beauty, profusion and wisdom, as in the immense domain of living beings. To inorganic substances have been given extent, impenetrability, an independent existence, and an indefinite, if not an interminable duration. To organized beings, variety and beauty of form, softness and flexibility of members, an existence dependent on almost every surrounding object, and a duration, which, though definite and frequently short, is in proportion to the perfection of its organization, full of enjoyment.

The laws of electricity, of chemistry, of mechanical philosophy, can explain all the phenomena of unorganized substances. Chemistry can ascertain their nature and composition, it can decompose their particles, and separate their constituent principles; it can do more, it can re-unite them, and reproduce the same mineral in the same form. But what Promethean skill can reanimate the lifeless body? Who can rearrange the organization which is once destroyed? Who can recompose the vegetable or the animal which has mouldered into dust?

Unorganized matter enjoys an independent existence. The orbs of heaven move along the firmament, and we know not if life is on their bosom. If, in our system, organized beings had never been created, if this earth had continued as in the

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