or matter and mind. Material objects consist of earths, metals, minerals, solids, fluids, and the bodies of animals and men. Spiritual objects embrace animal and human minds, different ranks and orders of angels and God.

Nature of Matter.

Chemistry relates principally to facts pertaining to matter, but in some degree to matter itself. It resolves bodies into their simplest elements; examines by experiment and observation these elements; and ascertains their properties. Bodies which it cannot resolve, and the elements of compound bodies, it regards as simple substances. On an ex

amination of all known elements, some are found to be ponderable, and others, as far as we have the means of ascertaining, imponderable. The earths, metals, minerals, and the like, are ponderable. Light, caloric and electricity are imponderable. Ponderable bodies derive their weight from a mutual attraction between them and the earth, and other bodies at sensible distance. This attraction is found to extend to the utmost limits of the solar system, and to be the cause of the revolution of the planets, and comets around the sun. Gravitation is the principle of union between the different parts of the earth, uniting them into one compact mass, and giving that mass a spheroidal form. It is also the principle of union in the solar system, binding all its great bodies together, and wheeling them in endless courses about their common center.

§ 331. Light, caloric and electricity have no perceptible gravitating powers, and answer purposes in the system with which such powers would be incompatible. Light and caloric are circulating mediums, and are constantly on the wing, from world to world, and from system to system. Many of the rays which are continually arriving from the fixed stars, and which we meet with by thousands and millions on every clear evening, have been on the way for years, and some of them for centuries; and during every instant of these long periods have been advancing at the rate of 95,000 miles a second. They are swift-winged messengers, performing the longest journeys with apparently undiminished speed; and moving with a velocity only surpassed by that of thought. The velocities of caloric and electricity seem to be equal to that of light.

§ 332. On a minute examination of bodies, and the elements of bodies, we find them capable of being resolved into particles of indefinitely small size. All kinds of bodies, the ponderable and imponderable, are capable of this analysis. Besides the attraction of gravitation, which belongs to all ponderable bodies, the elementary atoms of all bodies possess powers, both of attraction and repulsion, within indefinitely small spheres. These attractions are denominated attractions of cohesion, and of chemical affinity. They are the exercise of powers by which bodies are held together, and the attractions of chemical affinity are the means of uniting simple elements into compound bodies. Light, electricity, and caloric are subject to chemical affinities, and other attractions at insensible distances, equally with the elements of ponderable bodies; and electricity has attractions and repulsions peculiar to itself at sensible distances.

§ 333. By our last conceivable analysis, we resolve bodies into atoms, which are supposed to be indivisible, and of several different kinds. Each atom is a being possessing certain powers; a part of the frame-work of creation, and of the material universe; an agent capable of certain actions, and a subject capable of certain states. The powers of these atoms are of several different kinds, corresponding to the offices which they are designed to fulfil. They may all be comprehended, however, in powers of attraction and powers of resistance. But these powers are distributed to different atoms in different degrees, and under different limitations and restrictions, many of which are developed in chemistry, and many of which are entirely beyond the sphere of our knowledge. The atomic powers of resistance are restricted to limited spheres. Two atoms exercise no mutual resistances till they approach indefinitely near each other; but at the point at which they are ordinarily supposed to touch, they exercise mutual resistance. The same is true of aggregates consisting of many particles. When two surfaces meet, on being pressed, they resist. On a careful examination, however, it is supposed that in these cases the meeting is only apparent, and that resistance is exercised before the atoms touch, or in other words, that there is no such thing as contact of atom with atom, in the strict sense of the word. On approaching, at a certain distance, atoms mutually repel, and this repulsion at first slight, increases inversely in a certain ratio, as the distance is diminished.

The atomic sphere of repulsion, therefore, is a little sphere, extending to a certain indefinitely small distance from the center of the atom, in all directions, and apparently having a definite polarity, making it a little image of the entire earth. Within that sphere is contained the being, which we call an atom of matter, and there that being operates solely by the exercise of resistance, whenever his sphere is encroached upon by his neighbors. Wonderful being! Who shall penetrate thy seclusion, and bring thee forth? Who shall declare thine essence? Thou sittest a miniature world and in thy being is comprehended a mystery which no finit › mind can reveal.

§ 334. But the powers of this being are not confined to his atomic sphere. They extend to the utmost limits of the solar system. From underneath the mountains he reaches forth the hand of his power to the sun, and moon, and all the planets; and draws them into paths of order, which they would not otherwise find. This attractive power diminishes just in proportion to its diffusion by increasing distances, so as to be at all distances the same in its whole amount; and relatively, with respect to particular objects, to be inversely as the squares to the distances. All that we know of the atom, is its powers. These are exercised in two modes, within an indefinitely small sphere, they are exercised in resisting the approach of other particles; and beyond that sphere, in attracting other particles. In both these spheres, its powers are immense. The weight of superincumbent mountains cannot crush the smallest atom, or contract to a point the little sphere of its resistance; and intercepting world's cannot prevent the outgoing of its attracting power to the smallest sister atom, that may lie millions of miles from it. The existence of the atom is a matter of inference from its attractions and repulsions, on the principle that these facts must have a cause; we infer that it exists where it exercises its powers. Within the sphere of its repulsions and chemical and cohesive attractions, it exists as a subject or agent in those repulsions and attractions; and according to the same principle, throughout the entire sphere of its gravitation, it exists as an attracting agent, drawing other particles towards its center. The general opinion is, that the atoms of matter are substances which exist only in atomic spheres. Their existence in such spheres is inferred

solely from their operations there; and their existence as causes in the more widely extended spheres of the attraction of gravitation, is inferred from the equally valid ground of their operations throughout these wider spheres.

§ 335. The existence of an atom, throughout the wide sphere of its gravitation, is made as certain by the attraction of gravitation, as its existence in the indefinitely small spheres of cohesion and chemical affinity, and the still smaller sphere of repulsion, is made certain by its chemical affinity, cohesion and repulsion. Nothing, therefore, can be more erroneous than the common doctrines concerning the nature of matter as consisting of atoms, each of which is restricted entirely to indefinitely small spheres, and each of which exercises powers of attraction, in places beyond the sphere of its existence and extension. The indefinite extension of the sphere of the attraction of matter, proves the equal extension of matter as a subject of attraction. The true doctrine, therefore, is, that matter fills an indefinitely small sphere, as a principle of resistance; that beyond the sphere of its resistance, it has an indefinitely small sphere of chemical affinity and of cohesive attraction inclosing the other on all sides; and that exterior to this, it is extended throughout the entire solar system as a principle of gravitation. The impenetrability of matter is restricted to the indefinitely small spheres of its repulsion. In respect to the spheres of its attractions, it is not impenetrable; but all its atoms coexist in the same spaces, and are joint occupants of the same spheres.

The above conclusions have respect to ponderable atoms, and, with suitable modifications, may be applied equally to those of imponderable bodies.

§ 336. But what is the essence of this being so small and so exclusive in its powers of resistance, and so extended in its powers of attraction? The power we know; and we know it is an attribute which belongs to a subject; and we know the nature of the subject by its powers, and as far as its powers appear. Beyond this the field of human knowledge does not extend; and there is no such thing conceivable as an essence or substance, except relatively to its powers and effects. From the facts of the natural world we infer the existence of an immense number of beings possessing certain powers. All the powers of these beings in their

last analysis, are resolved into resistances and attractions, according to certain laws; and are mutual and relative. A single particle existing alone in the universe, would have no powers, and would perform no actions. Two particles would be capable of attracting and repelling each other, according to their relative positions; and an indefinite number of particles would exercise an indefinite number of repulsions and attractions. With rational views of the nature of matter as consisting of atoms which have indefinitely extended spheres of attraction, we review the general hypothesis that bodies do not actually touch in apparent contact, and find it erroneous. They not only come together in all cases of apparent contact, but in all cases of mutual gravitation. The earth and sun come together as subjects of mutual attractions; and all the particles meet, each gravitating particle in each, meeting every gravitating particle in the other. What myriads of meetings are thus affected! And what myriads of actions occur! We return again to the question, what is a material atom? It is an extended being possessing certain powers considered with respect to other beings, but possessing no powers absolutely.

§ 337. Ideas of material objects are common to all men, and in some degree to all the higher orders of animals. They are attained immediately after we become the subjects of sensations and consciousness, and continue to be exercised with such modifications as result from our more extended observations and reasonings, while life and consciousness continue. Our first ideas of material objects, are particular. By comparing particular objects, we discover their similarities and diversities, and classify them accordingly. These generalizations are handed down from age to age, and from generation to generation, and are taught by tradition, as a part of the hereditary wealth of the human

race.

As fast as new discoveries are made, and new generalizations are established, the previous system of ideas, is so modified as to make room for these additions, and to be in consistency with them. Previons to the time of Newton, the attraction of gravitation was not known to belong to the great bodies of the solar system, or to be the connecting link between all the separate masses and bodies of the earth, and other worlds. Mountains were seen to stand firmly on