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No two particles of matter can occupy the same space at the same time.

All bodies weigh heaviest at the earth's surface. A body that weighs 10 pounds at the earth's surface will weigh but 24 pounds 4,000 miles high.

Take two cog-wheels of the same size; let one stand still put the cogs together and put the other in motion, and when it has made one-half revolution around the standing wheel it will have made a full revolution on its own center, notwithstanding only one-half of the cogs of its own surface has touched the standing wheel.

The atmosphere is the lightest in wet, rainy weather; yet we find people very often who think different. The medium pressure of the atmosphere is about fifteen pounds to the square inch, but this is not always the case. The pressure will vary in the same locality, and sometimes be greater or less. The medium hight that atmospheric pressure will raise water is about 33 feet; but this calculation only holds good at the level of the sea, because as we ascend from the sea level the pressure becomes less; hence, our calculations for raising water by atmospheric pressure must be governed by the pressure that atmosphere has at the hight of the position above the sea level. Illustration: At sea level atmospheric pressure fifteen pounds to the square inch; one mile above sea level, about 12 pounds; two miles above, 10 pounds; three miles, 7 pounds; consequently, on an elevation three miles high, water cannot be raised but about 16 feet by the weight of the air.

The top or upper part of a wagon wheel passes through a greater amount of space in a given time when running than the bottom; or, in other words, runs the fastest.

The piston rod of a steam engine makes two complete stops at every revolution of the crank attached to the end of the pitman. HORSE POWER.-The average power of a horse is sufficient to raise a weight of about 23,000 pounds one foot per minute, but when calculating the horse power of a steam engine it is estitmated at 33,000 pounds. It then follows that a ten horse powers team engine is, in fact, about equal to fourteen average horses.

POWER OF STEAM.-One cubic foot of water converted into steam will raise the enormous weight of three and a half million pounds one foot, or seven hundred pounds one mile high. All bodies or particles of matter fall to the eath by the attraction of gravity, and their speed is in proportion to their density; but take away the resisting force of the atmosphere, then a cork or feather will fall as fast as a bullet.

Resultant motion may be illustrated by holding a ball or weight in your hand and dropping it from the top of your head while running, you will find that you cannot run fast enough to overtake the ball before it strikes the ground.

A ball may be shot from a cannon from the top of a tower on a horizontal plain, and another dropped from the mouth of the cannon at the same time, and they will both strike the earth at the same time, provided the surface be horizontal with the cannon.

Lever power is almost indispensable, or in other words, without it we could scarcely do anything; yet to take in consideration distance and speed, there is not a particle of power gained by a lever. Illustration: Suppose a lever 20 feet long, the fulcrum 2 feet from one end of the lever, 10 pounds on the long end of the lever is equal to 100 pounds on the short end; but to raise the 100 pounds one foot the ten pounds passes through 10 feet of space, consequently it travels ten times as fast as the 100 pounds, so all that is gained in power is lost in speed and distance; because if both ends of the lever was of the same length while one end of the lever was passing through ten feet of space the other end would pass through the same ten feet; and ten pounds would raise ten pounds ten feet high, or ten times as high as the ten pounds on the long end of the lever would raise the 100 pounds on the short end,

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Many theories have been propounded at different periods of the history of astronomy, respecting the original formation of our Solar System, as well as all other suns and systems, which it has pleased the GREAT CREATOR OF ALL THINGS to call into existence, but no one has gained so great favor or excited so violent opposition, as the theory first proposed by Sir William Herschel, and afterwards more especially applied by the celebrated La Place to the formation of the solar system.

This theory may be thus stated:-In the beginning all the matter composing the sun, planets, and satellites was diffused through space, in a state of exceedingly minute division, the ultimate particles being held asunder by the repulsion of heat. In process of time, under the action of gravitation, th mass assumed a round or globular shape, and the particles tending to the centre of gravity, a motion of rotation on an axis would commence. The great mass, now gradually cooling and condensing, must increase its rotary motion, thereby increasing the centrifugal force at the equator of the revolv ing mass, until, finally, a ring of matter is actually detached from the equator, and is left revolving in space by the shrinking away from it, of the interior mass. If now we follow this isolated ring of matter, we find every reason to believe that its particles will gradually coalesce into a globular form, and in turn form satellites, as it was itself formed. It is unnecessary to pursue the reasoning further, for the same laws which produce one planet from the equator of the central revolving mass, may produce many-until finally, the process is ended by a partial solidification of the central mass, so great, that gravity aided by the attraction of cohesion, is more than suf ficient to resist the action of the centrifugal force, and no fur ther change occurs.

It has been urged in favor of this theory, that it accounts for the striking peculiarities which are found in the organization of the solar system. That the rings of Saturn are positive proofs of the truth of the theory, they having cooled and condensed without breaking. That the individuals constituting a system thus produced, must revolve and rotate as do the planets and satellites, and in orbits of the precise figure and position, as those occupied by the planets. It accounts for the rotation of the sun on its axis, and presents a solution of the strange appearance connected with the sun called the Zodiacal Light. It goes further and accounts for the formation of single, double, and multiple suns and stars-and by the remains of chaotic matter in the interstics between the stars, and which are finally drawn to some particular sun, whose influence in the end preponderates, accounts for the comets which enter our system from every region in space.

In support of this theory it has been urged that the comets, in their organization, presents us with specimens of this finely divided nebulous or chaotic matter-and that the telescope reveals cloudy patches of light of indefinite extent, scattered throughout space, which give evidence of being yet unformed and chaotic. That many stars are found in which the bright nucleus or centre is surrounded by a halo or haze of nebulous light, and that round nebulous bodies are seen with the telescope, of an extent vastly greater than would fill the entire space encircled by the enormous orbit of the planet La Verrier, or having a diameter greater than 7,000 millions of miles.

Such are a few of the arguments in support of this most extraordinary theory. We now present the objections which have been most strongly insisted on. The retrogade motions of the satellites of Herschel, and their great inclination to the plane of the ecliptic can not be accounted for by this theory. That computation shows that no atmosphere of condensed nebulous matter can extend to so great a distance from the sun, as does the matter composing the Zodiacal Light, and, finally, that the nebulous matter in the heavens will ultimately be resolved into immense congeries and clusters of stars, whose great distance has hitherto defied the power of the best instruments.

In reply to the first objection, the friends of the theory doubt


the facts with reference to the satellites of Herschel. They reply that the matter composing the Zodiacal Light being in the nature of cometary matter, is thrown to a greater distance from the sun than gravity would warrant, by that power resid ing in the sun which is able on the approach of comets to project those enormous trains of light, which sometimes render them so wonderful. As to the last objection, it is urged that although many nebule will doubtless be resolved into stars, by using more powerful telescopes, yet that these same telescopes will reveal more new nebula which cannot be resolved, than they will resolve-and as to the existence of nebulous matter, it is perfectly demonstrated by the physical organization of comets, and the existence of nebulous stars.

Such was the state of the Astronomical argument, when Lord Rosse's Great Reflector was first applied to the exploration of the distant regions of space. In a religious point of view, this theory had excited no small amount of discussion, in consequence of its supposed Atheistical tendencies. The friends of the theory contend that it was no more Atheistical to admit the formation of the universe by law, than to acknowledge that it is now sustained by laws. Indeed since we must go to the first great cause for matter in its chaotic state, as well as for the laws which govern matter, that this theory gave to us a grander view of the omniscience and omnipotence of God than could be obtained from any other source. In fine, that it harmonized with the declaration of scripture, which tells us that "In the beginning God created the heavens and the earth, and the earth was without form and void." If the earth came into existence in its present condition, then it had form and was not void. Hence, this first grand declaration of the inspired writer must refer to the formation of the matter of which the heavens and earth were afterwards formed. Some went so far as to trace out dimly a full account of this theory in the order of creation, as laid down in Gensis.

Let us now proceed to the discoveries of Lord Rosse, and their influence on this greatly disputed theory. The space penetrating power of his six feet reflector is much greater than that of Sir William Herschel's great telescope, and it was anticipated that many nebula which were unresolved into clusters of stars by Hershel, would yield under the greater power and light of Lord Rosse's telescope. This has proved to be the

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