same is the case, if the nail be driven into a piece of lead the particles of the lead are separated from each other, and crowded together, to make room for the harder body, but the 'particles themselves are by no means penetrated by the nail.

When a piece of gold is dissolved in an acid, the particles of the metal are divided, or separated from each other, and 'diffused in the fluid, but the particles of gold are supposed still to be entire, for if the acid be removed, we obtain the gold again in its solid form, just as though its particles had never been separated.

Extension. Every body, however small, must have length, breadth, and thickness, since no substance can exist without them. By extension, therefore, is only meant these qualities. Extension has no respect to the size, or shape of a body. The size, and shape of a block of wood a foot square is quite dif. ferent from that of a walking stick. But they both equally possess length, breadth, and thickness, since the stick might be cut into little blocks, exactly resembling in shape the large one. And these little cubes might again be divided until they were only the hundredth part of an inch in diameter, and still it is obvious, that they would possess length, breadth, and thickness, for they could yet be seen, felt, and measured. But suppose each of these little blocks to be again divided a thousand times, it is true we could not measure them, but still they would possess the quality of exten'sion, as really as they did before division, the only difference being in respect to dimensions.

Figure, or form, is the result of extension, for we cannot conceive that a body has length and breadth, without its also having some kind of figure, however irregular.

Some solid bodies have certain, or determinate forms, which are produced by nature, and are always the same,s wherever they are found. Thus a crystal of quartz has six sides, while a garnet has twelve sides, these numbers being invariable. Some solids are so irregular, that they cannot

When a nail is driven into a board, or piece of lead, are the particles of these bodies penetrated or separated? Are the particles of gold dissolved, or only separated by the acid? What is meant by extension? In how many directions do bodies possess extension? Of what is figure, or form, the result? Do all bodies possess figure? What solid re regular in their forms? What bodies are irregular?

mathematical figure.

be compared with any This is the case with the fragments of a broken rock, chips of wood, fractured glass, &c.

Fluid bodies have no determinate forms, but take their shapes from the vessels in which they happen to be placed.

Divisibility. By the divisibility of matter, we mean that a body may be divided into parts, and that these parts may again be divided into other parts.

It is quite obvious, that if we break a piece of marble into two parts, these two parts may again be divided, and that the process of division may be continued until these parts are so small as not individually to be seen or felt. But as every body, however small, must possess extension and form, so we can conceive of none so minute but that it may again be divided. There is, however, in all probability, a limit, beyond which the particles of matter cannot be divided, for we do not suppose that the atoms of which bodies, are composed, are themselves divisible, or can be broken, and therefore here, divisibility must end. But under what circumstances this takes place, or whether it is in the power of man during his whole life, to pulverize any substance so finely, that it may not again be broken, is unknown.

We can conceive, in some degree, how minute must be the particles of matter, from circumstances that every day come within our knowledge.

A single grain of musk will scent a room for years, and still lose no appreciable part of its weight. Here, the particles of musk must be floating in the air of every part of the room, otherwise they could not be every where perceived.

Gold is hammered so thin, as to take 28,000 leaves to make an inch in thickness. Here, the particles still adhere to each other, notwithstanding the great surface which they cover,―a single grain being sufficient to extend over a surface of fifty square inches.

The ultimate particles of matter, however widely they may be diffused, are not individually destroyed, or lost, but under certain circumstances, may again be collected into a body

What is meant by divisibility of matter? Is there any limit to the divisibility of matter? Are the atoms of matter divisible? What examples are given of the divisibility of matter? How many leaves of gold does it take to make an inch in thickness? How many square inches may a grain of gold be made, to cover?

without change of form. Mercury, water, and many other substances, may be converted into vapor, or distilled in close vessels, without any of their particles being lost. In such cases, there is no decomposition of the substances but only a change of form by the heat, and hence the mercury and water, assume their original state again on cooling.

When bodies suffer decomposition or decay, their elemen. tary particles, in like manner, are neither destroyed nor lost,. but only enter into new arrangements, or combinations with other bodies.

When a piece of wood is heated in a close vessel, such as a retort, we obtain water, an acid, several kinds of gas, and there remains a black, porous substance, called charcoal. The wood is thus decomposed, or destroyed, and its particles take a new arrangement, and assume new forms, but that nothing is lost is proved by the fact, that if the water, acid, gases, and charcoal be collected and weighed, they will be found exactly as heavy as the wood was, before distillation.

Bones, flesh, or any animal substance, may in the same manner be made to assume new forms, without losing a particle of the matter which they originally contained.

The decay of animal, or vegetable bodies in the open air, or in the ground, is only a process by which the particles of which they were composed, change their places, and assume new forms.

The decay, and decomposition of animals and vegetables on the surface of the Earth form the soil, which nourishes the growth of plants and other vegetables; and these in their turn, form the nutriment of animals. Thus is there a perpetual change from death to life, and from life to death, and as constant a succession in the forms and places, which the particles of matter assume. Nothing is lost, and not a particle of matter is struck out of existence. The same matter of which every living animal, and every vegetable was formed, before and since the flood, is still in existence. As nothing is lost or annihilated, so it is probable that nothing has been added, and that we, ourselves, are composed of particles of

Under what circumstances may the particles of matter again be collected in their original form? When bodies suffer decay, are their particles lost? What becomes of the particles of bodies which decay? Is it probable that any matter has been annihilated, or added, since the first creation?

matter as old as the creation. In time, we must in our turn, suffer decomposition, as all forms have done before us, and thus resign the matter of which we are composed, to form new existences.

Inertia. Inertia means passiveness, or want of power. Thus matter is, of itself, equally incapable of putting itself in motion, or of bringing itself to rest when in motion.

It is plain that a rock on the surface of the earth, never changes its position in respect to other things on the earth. It has of itself no power to move, and would, therefore, forever lie still, unless moved by some external force. This fact is proved by the experience of every person, for we see the same objects lying in the same positions all our lives. Now it is just as true, that inert matter has no power to bring itself to rest, when once put in motion, as it is, that it cannot put itself in motion, when at rest, for having no life, it is perfectly passive, both to motion and rest, and therefore either state depends entirely upon circumstances.

Common experience proving that matter does not put itself in motion, we might be led to believe, that rest is the natural state of all inert bodies, but a few considerations will shew, that motion is as much the natural state of matter as rest, and that either state depends on the resistance, or impulse of external causes.

If a cannon ball be rolled upon the ground, it will soon cease to move, because the ground is rough, and presents impediments to its motion, but if it be rolled on the ice, its motion will continue much longer, because there are fewer impediments, and consequently, the same force of impulse will carry it much farther. We see from this, that with the same impulse, the distance to which the ball will move must depend on the impediments it meets with, or the resistance it has to overcome. But suppose that the ball and ice were both so smooth as to remove as much as possible the resistance caused by friction, then it is obvious that the ball would continue to move longer, and go to a greater distance. Next suppose we avoid the friction of the ice, and throw the ball through the air, it would then continue in motion still longer with the same

What is said of the particles of matter of which we are made? What does inertia mean? Is rest or motion the natural state of matter? Why does the ball roll further on the ice than on the ground? What does this prove?

force of projection, because the resistance of the air is less. than that of the ice, and there is nothing to oppose its constant motion, except the resistance of the air, and its own weight, or gravity.

If the air be exhausted, or pumped out of a vessel by means of an air pump, and a common top, with a small, hard point, be set in motion in it, the top will continue to spin for hours, because the air does not resist its motion. A pendulum, set in motion, in an exhausted vessel, will continue to swing, without the help of clock work, for a whole day, because there is nothing to resist its perpetual motion, but the small friction at the point where it is suspended.

We see, then, that it is the resistance of the air, of friction, and of gravity, which cause bodies once in motion cease moving, or come to rest, and that dead matter of itself, is equally in capable of causing its own motion, or its own rest.

We have perpetual examples of the truth of this doctrine, in the moon, and other planets. These vast bodies move through spaces which are void of the obstacles of air and friction, and their motions are the same that they were thousands of years ago, or at the beginning of creation.

Attraction. By attraction is meant that property, or quality in the particles of bodies, which make them tend toward each other.

We know that substances are composed of small atoms, or particles, of matter, and that it is a collection of these, united together, that forms all the objects with which we are acquainted. Now when we come to divide, or separate any substance into parts, we do not find that its particles have been united, or kept together by glue, little nails, or any such mechanical means, but that they cling together by some power, not obvi. ous to our senses. This power we call attraction, but of its nature or cause, we are entirely ignorant. Experiment and observation however, demonstrate, that this power pervades all material things, and that under different modifications, it

Why, with the same force of projection, will a ball move further through the air than on the ice? Why will a top spin, or a pendulum swing longer, in an exhausted vessel than in the air? What are the causes which resist the perpetual motion of bodies? Where have we an example of continued motion, without the existence of air and friction? What is meant by attraction? What is known about the cause of attraction? Is attraction common to all kinds of matter, or not?