greatest quantity of matter, the water is raised upwards, or in the direction of the length of the tube. On the outside of the tube, the opposite surfaces, it is obvious, cannot act on the same column of water, and therefore the influence of attraction is here hardly perceptible in raising the fluid. This seems to be the reason why the fluid rises higher on the inside than on the outside of the tube.

53.

great variety of porous substances are capable of this kind of attraction. If a piece of sponge or a lump of sugar be placed, so that its lowest corner touches the water, the fluid will rise up and wet the whole mass. In the same manner, the wick of a lamp will carry up the oil to supply the flame, though the flame is several inches above the level of the oil. If the end of a towel happens to be left in a basin of water, it will empty the basin of its contents. And on the same principle, when a dry wedge of wood is driven into the crevice of a rock, and afterwards moistened with water, as when the rain falls upon it, it will absorb the water, swell, and sometimes split the rock. In Germany, mill-stone quarries are worked in this manner.

54. CHEMICAL ATTRACTION takes place between the particles of substances of different kinds, and unites them into one compound.

55. This species of attraction takes place only between the particles of certain substances, and is not, therefore, a universal property. It is also known under the name of chemical affinity, because it is said, that the particles of substances having an affinity between them, will unite, while those having no affinity for each other do not readily enter into union.

56. There seems, indeed, in this respect, to be very singular preferences, and dislikes, existing among the particles of matter. Thus, if a piece of marble be thrown into sulphuric acid, their particles will unite with great rapidity and commotion, and there will result a compound differing in all respects from the acid or the marble. But if a piece of glass, quartz, gold, or silver, be thrown into the acid, no change is produced on either, because their particles have no affinity.

Why does the water rise higher in the tube than it does on the outside? Give some common illustrations of this principle. What is the effect of chemical attraction? By what other name is this kind of attraction known? What effect is produced when marble and sulphuric acid are brought together? What is the effect when glass and this acid are brought together? What is the reason of this difference?

The 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.

5. 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.

6. 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 snape of a body, The size and shape of a block of wood a foot square is quite different 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 extension, as really as they did before division, the only difference being in respect to dimensions.

7. 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.)

8. Some solid bodies have certain or determinate forms which are produced by nature, and are always the same 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 be compared with any mathematical figure. This is the case with the fragments of a broken rock, chips of wood, fractured glass, &c.

Are the particles of gold dissolved, or only separated, by the acid? What is meant by extension? In how many directions do bodies pos sess extension? Of what is figure, or form, the resuit? Do all bodies possess figure? What solids are regular in their forms: What be dies are irregular?

9. Fluid bodies have no determinate forms, but take their shapes from the vessels in which they happen to be placed. 10. 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.)

11. 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, possibly a limit, beyond which bodies cannot be actually divided, for there may be reason to believe that the atoms of matter are inidvisible by any means in our power. 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.

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

13. 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.

14. Gold is hammered so thin, as to take 282,000 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.

15. 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 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

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? Under what circumstances may the particles of matter again be collected in their original

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.

16. When bodies suffer decomposition or decay, their elementary particles, in like manner, are neither destroyed nor lost, but onlyCenter into new arrangements or combina tions with other bodies.

17. 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, gasses, and charcoal, be collected and weighed, they will be found exactly as heavy as the wood was, before distillation.

18. 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.

19. 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.

20. 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 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.

21. INERTIA.-Inertia means passiveness or want of

When bodies suffer decay, are their particles lost? What becomes of the particles of bodies which decay? Is it probable that any matter nas been annihilated or added, since the first creation? What is said of the particles of matter of which we are made? What does inertia mean?

power.) Thus matter is, of itself, equally incapable of put ting itself in motion, or of bringing itself to rest when in

motion.

22. 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, for ever 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 pow er 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.

23. 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 show that motion is as much the natural state of mat. ter as rest, and that either state depends on the resistance, or impulse, of external causes.

24. 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 im pulse 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 force of projection, because the air alone, presents less impediment than the air and ice, and there is now nothing to oppose its constant mo. tion, except the resistance of the air, and its own weight, or gravity.

25. If the air be exhausted, or pumped out of a vessel by

Is rest or motion the natural state of matter? Why does the ball roll farther on the ice than on the ground? What does this prove? Why, with the same force of projection, will a ball move farther through

the air than on the ice?