Vacuum

“ Practically every physician advocates it, and it is compulsory in some towns and cities. Deaths have occurred from it, but they are very infrequent.
Vacuum.—The perfect vacuum, which it is impossible to produce, is space without air or atmosphere. Vacuums are made by pumping all the air out of a receptacle or chamber. In a vacuum, everything falls at the same rapidity, as there is nothing to buoy it up, a feather descending as rapidly as lead shot. ”

“ The earth, air, water and fire and vacuum, are severally the receptacles of many properties; but it is the vacuous intellect which is the great repository of these, that appear as dreams hovering all about it. ”

“ But the universal method of producing a vacuum is by air pumps. An
absolute vacuum means the entire absence of gas or air, something almost
impossible to produce. A high vacuum is sometimes understood to mean one
in which the path of the molecules is equal in length to the diameter of
the containing vessels, as in Crookes' Radiometer and other apparatus
for illustrating the radiant condition of matter. ”

“ Because, my dear Captain, we are moving through a vacuum, and because all bodies fall or move—the same thing—with equal velocity through a vacuum, no matter what may be their shape or their specific gravity. ”

“ For handling and transporting liquid gases glass receptacles with a double skin from which all air has been exhausted are employed. The surrounding vacuum is so perfect an insulator that a “Dewar bulb” full of liquid air scarcely cools the hand, though the intervening space is less than an inch. This fact is hard to square with the assertion of scientific men that our atmosphere extends but a hundred or two miles from the earth’s surface, and that the recesses of space are a vacuum. ”

“ A vacuum is defined very properly as an empty space; a space in which there is neither steam, water or air—the absolute absence of everything. The condenser is the apparatus by which, through the cooling of the steam by means of cold water, a vacuum is obtained. ”

“ Vacuum begin to act disturbed. That are sign he want to eat dust.
5—Find some dust. Lead Hon. Vacuum to this and say, “Sick him!” Snorts! Hon. Dust will jump to nowhere while Hon. Vacuum howell for more food.
What are this Hon. Vacuum, anyhows? Hon. Dictionary Book say “Vacuum are Nothing.” How could Mr. Danl Webster speak such untruth by his Dictionary? Vacuum cannot be Nothing and yet make so much noises.
This intellectual Vacuum machinery resemble ostriches in what they eat. He delight to sip up tacks, needles, buttons and other hard groceries. ”

“ Can man, by any rational theory, combine a vacuum and a substance, and create a result that is neither material nor vacuity, neither something nor nothing, and yet an intensified all; being more attenuated than the most perfect of known vacuums, and a conductor better than the densest metal? This we do when we attempt to describe the scientists' all-pervading ether of space, and to account for its influence on matter. ”

“ Objective Reality of Vacuum.—The second thing we must ascertain is whether space void of matter be a mere nothing, or an objective reality. Though Balmes and most modern philosophers hold that vacuum is mere nothingness, we think with other writers that the contrary can be rigorously demonstrated. Here are our reasons.
First, nothingness is not a region of movement. But vacuum is a region of movement. Therefore, vacuum is not mere nothingness. ”

“ Examine the tube for vacuum by noting the sound the mercury makes when allowed to roll gently about in the large chamber. If it makes a clear, metallic click, the vacuum is good; but, if the sound is dull and the mercury sluggish in moving, the vacuum is either partially or wholly destroyed. ”

“ Next, he says, That an absolute Vacuum, is neither an Accident, nor a Body, nor yet Nothing, but Something, because it has a being; which opinion seems to me like that of the divine Soul; but I suppose Vacuum is not the divine Soul, nor the divine Soul, Vacuum ”

“ Is not the Heat of the warm Room convey'd through the Vacuum by the Vibrations of a much subtiler Medium than Air, which after the Air was drawn out remained in the Vacuum? And is not this Medium the same with that Medium by which Light is refracted and reflected, and by whose Vibrations Light communicates Heat to Bodies, and is put into Fits of easy Reflexion and easy Transmission? And do not the Vibrations of this Medium in hot Bodies contribute to the intenseness and duration of their Heat? ”

“ It presses with a force of about 14.7 lbs. per square
inch under the influence of the force of gravity. The term vacuum in
practise refers to any space from which air has been removed. It may be
produced chemically. Air may be displaced by carbonic acid gas and the
latter may be absorbed by caustic alkali or other chemical. The air may
be expelled and the space may be filled with steam which is condensed to
produce the vacuum. Of course in all cases the space must be included in
an hermetically sealed vessel, such as the bulb of an incandescent lamp. ”

“ Though a vacuum does not prevent the electricity from being excited, it will not serve as a conductor of it when it has been excited: if an arc from the nerves to the muscles be intercepted by the smallest vacuum, no contractions take place. ”

“ It is evident that in such a case the velocity of entry of air into a vacuum on the ground floor would be greater than into a vacuum on any of the higher storeys, owing to the greater velocity acquired through the increased action of gravity. ”

“ In such a vacuum the repulsion by heat was still found to be decided and energetic.
I next tried experiments in which the rays of the sun, and then the different portions of the solar spectrum, were projected on to the delicately-suspended pith-ball balance. In vacuo the repulsion by a beam of sunlight is so strong as to cause danger to the apparatus, and resembles that which would be produced by the physical impact of a material body. ”

“ When it was first noticed in Galileo's time that water would not ascend in the suction pipe of a pump to a greater height than 32 feet, the old law that nature abhors a vacuum was modified, and the reasons why and the conditions under which Nature abhors a vacuum were discovered. The suction of fluids was brought under the general law of mechanical pressure. The doctrine that Nature abhorred a vacuum had been a fair generalization and expression of the facts of this kind that up to that time had been observed. ”

“ But, were it possible Nature's Parts could wander and stray in, and out of Vacuum, there would be a Confusion; for, where Unity is not, Order cannot be: Wherefore, by the Order and Method of Nature's corporeal Actions, we may perceive, there is no Vacuum: For, what needs a Vacuum, when as Body and Place is but one thing ”

“ If the vacuum passes over water, the water may rise in it in a body, or column, to near the height of thirty-two feet.
If it passes over houses, it may burst their windows or walls outwards, pluck off the roofs, and pluck up the floors, by the sudden rarefaction of the air contained within such buildings; the outward pressure of the atmosphere being suddenly taken off: so the stopped bottle of air bursts under the exhausted receiver of the air-pump. ”

“ As it is more convenient to regard a vacuum as a limiting case of extreme rarefaction than to give a special consideration to the possible formation of empty spaces within the given mass, the term new parts will be used to include any empty spaces which may be formed, when such have not existed initially. We will use to denote the infinitesimal energy, entropy, and volume of any one of these new parts, and the infinitesimal quantities of its components. ”

“ A further study of this phenomenon reveals the significant fact that just as much of each gas diffuses into the space of the other as would expand into a vacuum of the same size. In fact each gas is, at all temperatures, a vacuum to every other. This fact remains an unsolved mystery, except we admit the existence of molecules and of molecular spaces far outmeasuring the molecules themselves. ”

“ From that moment I took up the notion 91that it is not repugnant to the nature of things that there should be a vacuum, but merely that it is difficult to produce. To explain myself more clearly: if we allow that the air has weight, there is no difference between air and water except in degree. ”

“ Small and long glass tubes, exhausted of air, and bent in many irregular crooks and angles, will, when properly electrified, exhibit a very beautiful representation of vivid flashes of lightning.
[G] A Torricellian vacuum is made by filling a tube with pure mercury and then inverting it, in the same manner as in making a barometer; for as the mercury runs out, all the space above will be a true vacuum. ”

“ But if, as in a vacuum, as some say, the vacuum is surrounded by this universe; the other, again, is without substance, for the substance of a vacuum is nothing. But if as accidents, first, indeed, this is impossible; for the thing that wants substance cannot be in any place; for substance is, as it were, the vehicle underlying the accident. ”

“ The third objection carries the matter still farther, and not only asserts, that the idea of a vacuum is real and possible, but also necessary and unavoidable. This assertion is founded on the motion we observe in bodies, which, ‘tis maintain’d, wou’d be impossible and inconceivable without a vacuum, into which one body must move in order to make way for another. ”

“ It is, therefore, erroneous to say that there is no vacuum except by the application of force, and that every space is full either of air or water or some other substance. But in proportion as any one of these particles recedes, some other follows it and fills the vacant space; therefore there is no continuous vacuum, except by the application of some force (like suction) —that is to say, an absolute vacuum is never found, except as it is produced artificially." Hero brings forward some thoroughly convincing proofs of the thesis he is maintaining. ”

“ Mean Free Path—Radiant Matter.—I have long believed that a well-known appearance observed in vacuum-tubes is closely related to the phenomena of the mean free path of the molecules. When the negative pole is examined while the discharge from an induction coil is passing through an exhausted tube, a dark space is seen to surround it This dark space is found to increase and diminish as the vacuum is varied in the same way that the mean free path of the molecules lengthens and contracts. ”

“ On applying an arc, the one exhibited strong and the other faint contractions; from which it appeared that the vacuum had occasioned some loss of the animal electricity; as the muscular and nervous parts subjected to experiment belonged to the same frog, this evidently showed that the whole difference arose from the action of the vacuum.
IV. It is well known that a vacuum absorbs common electricity; and therefore it need not excite any wonder that in the present experiment it should have dispersed some of the animal electricity. ”

“ If an electric bell is placed in a bell jar attached to an air pump, as in Fig. 315, on exhausting the air the loudness of the sound is found to diminish, indicating that in a perfect vacuum no sound would be transmitted. This effect of a vacuum upon the transmission of sound is very different from its effect upon radiation of heat and light. Both heat and light are known to pass through a vacuum since both come to the earth from the sun through space that so far as we know contains no air or other matter. ”

“ We say the space inside is a vacuum. If the bulb is broken there is a loud report as the air rushes in. Is the bulb really empty after the air is pumped out? Is anything left in the bulb around the carbon thread? Turn on the electric current and the carbon thread becomes white hot. The light from the white-hot carbon thread goes out through the vacuum. There is nothing in the vacuum that we can see or feel or handle, but something must be there to carry the light from the carbon thread. The light of the sun comes to the earth through ninety-three million miles of space. ”

“ For, in the next place, our experiments seem to teach that the supposed aversation of Nature to a vacuum is but accidental, or in consequence, partly of the weight and fluidity, or, at least, fluxility of the bodies here below; and partly, and perhaps principally, of the air, whose restless endeavour to expand itself every way makes it either rush in itself or compel the interposed bodies into all spaces where it finds no greater resistance than it can surmount. ”

“ Let us first apply the elastic theory to the case of the so-called vacuum. If we write for the amplitude measured in the middle between two nodal planes, the velocities of displacement will be as and the kinetic energy will be represented by where is a constant depending on the density of the medium. The potential energy, which consists in distortion of the medium, may be represented by where is a constant depending on the rigidity of the medium. ”

“ The vacuum thus produced is by no means so perfect as the “Torricellian vacuum,” [12] the name given to the unoccupied space above the column of mercury in a barometer.
Various substances may be placed in a receiver to show the expansive tendency of air. A piece of wood immersed in a jar of water will throw off thousands of little bubbles. A shriveled apple will become round and plump. The air in an empty rubber bag will often expand so as to fill the receiver. Air in a thin glass vessel, tightly corked, will expand so as to burst the vessel into fragments. ”