Dispersion

“ The fact that the dispersion takes place as a function of the time according to a rigorous exponential law, the quantity which is destroyed in a given time being exactly proportional to the quantity present, seems to indicate that the substance not destroyed remains identical with itself. ”

“ As for dispersion, if it be assumed that light is given forth from the entire surface of the sun equally in all directions, the lateral pressure of dispersion at each spherical zone, and at any distance—if it exists—would be equal, and there would be perfect equilibrium between adjacent cones of light ”

“ Hence instead of concentration we have dispersion.
The united action of the winds and the unity of the atmosphere result from this dispersion. The displacement of one molecule produces the displacement of another. The vast body of air becomes subject to one agitation. To these profound causes of coalition we must add the irregular surface of the earth, whose mountains furrow the atmosphere, contorting and diverting the winds from their course, and determining the directions of counter currents in infinite radiations. ”

“ The simplest way of showing dispersion is to refract a narrow beam of sunlight through a prism of glass or prismatic vessel containing water or other clear liquid. As the light is twice refracted, the dispersion is increased, and the rays, after transmission through the prism, form a divergent system, which may be allowed to fall on a sheet of white paper, forming the well-known solar spectrum. ”

“ Such bodies show strong absorption bands in those colours which they reflect, while of the transmitted light that which is of a slightly greater wave-length than the absorbed light has an abnormally great refrangibility, and that of a slightly shorter wave-length an abnormally small refrangibility. The name given to this phenomenon,—“anomalous dispersion”—is an unfortunate one, as it has been found to obey a regular law. ”

“ And since, by the conditions of the case, they cannot return to these remote regions in the shape of concrete masses, they must return in the shape of diffused masses. Action and reaction being equal and opposite, the momentum producing dispersion, must be as great as the momentum acquired by aggregation; and being spread over the same quantity of matter, must cause an equivalent distribution through space, whatever be the form of the matter. ”

“ The natural dispersion of all animals is gradual, so that their constitutions are enabled, from the slowness of the transition, to accommodate themselves, by an alteration in covering and habit, to surrounding circumstances, which would, were the variations abrupt, speedily destroy it. ”

“ It happens that we have traditions of a great dispersion from the very centre we have been led to fix, the neighborhood of Atlas or Gibraltar, and that to this dispersion tradition has given a date over eleven thousand years ago ”

“ Shadow upon the one side, bright light upon the other, azure above and swallows. Ever rolling the human stream flows, mostly on the south side yonder, near enough to be audible, but toned to bearableness. A stream of human hearts, every atom a living mind filled with what thoughts?—a stream that ran through Rome once, but has altered its course and wears away the banks here now and triturates its own atoms, the hearts, to dust in the process. ”

“ The very distribution of contrary indications, leads them to believe in a partial displacement of the mass of waters from one region towards another, and even from the one side of an inland sea towards the opposite side; a displacement which might be owing to fugitive or more or less durable causes, such as a variation of temperature in the polar regions, the action of winds and of currents, modified by the greater or less quantity of water in the rivers that feed the different basins, upon the sides opposed to their direction. ”

“ And just as all particular things are evolved by the force of attraction and dissolved by the force of repulsion, a state of concentration or aggregation in the individual perpetually alternating with a state of diffusion or segregation, so it is also with the material universe as a whole. ”

“ How in the zero, in which there were no ‘concrete forms’ and no ‘preceding histories,’ did the first movement towards the plenished arch of heaven and the fruitful earth arise? Concentration and diffusion, it is affirmed, are universally observed physical processes. ”

“ If the pressure at every point of a given closed surface be known, and the distribution of sources within the surface be also known, then only one distribution of pressures can exist within the surface. ”

“ But on account of the changes incessantly taking place in the distribution of matter upon the earth's surface, and perhaps also within the surface, the amplitude of the polar displacement, and perhaps the principal period of revolution of the one axis about the other, are changeable, the changes taking place in a rather complicated way according to laws as yet not fully determined. ”

“ And that this imperceptible something—fluid I will say, for want of a better term—now invisible and unknown to man, is as a medium in which the earth, submerged, floats as a speck of dust in a flood of space? ”

“ As I strolled I became aware of a motionless figure ahead of me,—one that seemed oddly familiar; the set of the shabby overcoat on the stooping shoulders, the unconscious pose contributed to a certain sharpness of individuality; in the act of challenging my memory, I halted. The man was gazing at the seascape, and his very absorption gave me a sudden and unfamiliar thrill. The word absorption precisely expresses my meaning, for he seemed indeed to have become a part of his surroundings,—an harmonious part. ”

“ But, on the other hand, if an impressible person, standing alone over the brink of one of these processions, should behold it, not in its atoms, but in its aggregate,—as a mighty river of life, massive in its tide, and black with mystery, and, out of its depths, calling to the kindred depth within him,—then the contiguity would add to the effect. ”

“ Our stratification is like the ocean, where every individual [Pg 399] drop is free to move, and where from the sternest depths of the mighty deep any drop may come up to glitter on the highest wave that rolls. ”

“ When a substance in solution diminishes the surface tension at the dividing surface, its concentration is increased; it is absorbed. When a substance in solution increases the surface tension at the dividing surface, its concentration is diminished. ”

“ Diffusion not only sets up currents in the water and in the solutes, but it also determines movements in any particles that may be in suspension, such as blood corpuscles, particles of Indian ink, and the like. ”

“ But where surfaces of discontinuity are considered, a system is not regarded as practically unstable, unless the disturbance which will produce such a result is very small compared with the quantities relating to surfaces of discontinuity of any appreciable magnitude. ”

“ Distance or space, in its simple abstract conception, to avoid confusion, I call expansion, to distinguish it from extension, which by some is used to express this distance only as it is in the solid parts of matter, and so includes, or at least intimates, the idea of body : whereas the idea of pure distance includes no such thing. ”

“ Let me now describe the sole possible mode in which it is conceivable that matter could have been diffused through space, so as to fulfil the conditions at once of irradiation and of generally equable distribution. ”

“ The mathematical calculation of the distribution of two fluids, all the particles of which attract and repel each other according to the above law, was a problem of no ordinary difficulty; as may easily be imagined, when it is recollected that the attraction and repulsion determine the distribution, and the distribution reciprocally determines the attraction and repulsion. ”

“ But if as well in water as in Air, there be no Renitence against simple Division, how can we say, that the water is easlier divided than the Air? We know not how to extricate our selves from the Equivocation: whereupon I return to answer, that Resistance of absolute Division is one thing, and Resistance of Division made with such and such Velocity is another. ”

“ All these three kinds of diffusion—the diffusion of matter, of momentum, and of energy—are carried on by the motion of the molecules. The greater the velocity of the molecules, and the farther they travel before their paths are altered by collision with other molecules, the more rapid will be the diffusion. ”

“ She appeared, in relation to the future, to resemble a diver in the deep sea, who, the deeper he strives, finds a more resistant pressure, till, at no great depth, resistance becomes prohibition, and he can no further strive. ”

“ It is clearly more profitable to examine the associations and relations of diffusion and convergence, the conditions under which they supplement each other. Besides parallels springing up wholly independently, there are two ways in which their relations to diffusion may be conceived. An original single growth or wave of diffusion may differentiate into local or temporal modifications, which even after separation continue to develop along parallel lines or reconverge. ”

“ But when this wide spread, and apparently uninvestigable aggregation of particles, comes under the scrutinizing eye of science, a beautiful and systematic arrangement of undigenous formations are clearly developed. ”

“ I have sometimes seen a ditch, the water of which, though really shallow, has appeared to careless observers to be very deep, for no other reason but because it was muddy. Believe me, my lord, experienced and penetrating observers are not so to be taken in. ”

“ The stream has its divisions; listen to words that are a commentary upon the meaning of this verse, 'All these worketh that one and the selfsame Spirit, dividing unto every man severally as He will'—an infinite variety, an endless diversity, according to all the petty wants of each that is supplied thereby. ”

“ The centres of disturbance, which positively exceed the mean consistency in virtue of the pyknosis or condensation, form the ponderable matter of bodies; the finer, intermediate substance, which occupies the space between them, and negatively falls below the mean consistency, forms the ether, or imponderable matter. ”

“ Stop the circulation of the terrestrial fluids and we have stagnation, putrefaction, death; stop the circulation of the fluids in man, and stagnation, absorption, calcification from old age, and death ensue. ”

“ The Morphogenic Effects of Diffusion.—Many interesting experiments may be made showing variations of the lines of force in a field of diffusion, and how liquids subjected only to differences of osmotic pressure diffuse and mix with one {60}another in definite patterns. When a liquid diffuses in another undisturbed by the influence of gravity, it produces figures of geometric regularity, and we may thus obtain figures and forms of infinite variety. ”

“ The conception of poles of diffusion is of the greatest importance in biology, throwing a flood of light on a number of phenomena, such as karyokinesis, which have hitherto been regarded as of a mysterious nature. ”

“ We receive the impression of the falling of a large mass of water, descending always from the same height and with the same difficulty. The scattering of the drops of water, the formation of froth, the sound of the fall by the roaring and by the froth, are constantly produced by the same causes, and, consequently, are always the same. ”

“ This rhythm of evolution and dissolution, completing itself during short periods in small aggregates, and in the vast aggregates distributed through space completing itself in periods which are immeasurable by human thought, is, so far as we can see, universal and eternal: each alternating phase of the process predominating—now in this region of space, and now in that—as local conditions determine. ”

“ The explanation of the phenomena thus far lies on the surface, and it is scarcely possible to advance any other; but why should one stage become changed more frequently or to a greater extent than the other? why should one portion be induced to change more frequently or more strongly than another? ”

“ Accordingly all that we are really entitled to hold, as the outcome of sound speculation, is the conception of innumerable systems of worlds concentrating out of nebulous masses, and then rushing together and dissolving into similar masses, as bubbles unite and break up—now here, now there—in their play on the surface of a pool, and to this tremendous series of events we can assign neither a beginning nor an end. ”

“ Could we suppose produced on the present globe some general change of conditions in the sea, on the land, and in the atmosphere—either simultaneously, or by communication from a central area of disturbance —the effects upon organic life might be everywhere manifested, though unequally and variously. ”

“ A constant Influx of the external Air, if it does not carry off some Part of the Spirit already generated, yet certainly catches up and dissipates the fine, subtile, or oleaginous and saline Particles, whereof the Spirit is made, and thus considerably lessens the Quantity. ”

“ Suppose that the whole of the medium is moved backwards in space along the line of propagation so that the undisturbed portions travel with the velocity U. The disturbance, or the train of waves, is then fixed in space, though fresh matter continually enters the disturbed region at one end, undergoes the disturbance, and then leaves it at the other end. ”

“ The mass of associated systems forms the 'reductives' of each individual system. In dissociated systems the controlling influence of the 'reductive mass' is lost and the result is an over-activity, unchecked by any counteracting tendencies. ”

“ Why should the disappearance of a condition shock a system of disappearances and appearances, which is another name for the unceasing orbit of revolutions in the face of the earth, and which is nature? An individual counts for nothing in the lapse of twenty-four hours gone or come. ”