Fluid

“ Nor do I much concern my self, to determine what the Figure of the particles of this exceedingly subtile fluid medium must be, nor whether it have any interstitiated pores or vacuities, it being sufficient to solve all the Phænomena to suppose it an exceedingly fluid, or the most fluid body in the world, and as yet impossible to determine the other difficulties.
That being so exceeding fluid a body, it easily gives passage to all other bodies to move to and fro in it. ”

“ Having considered all the substances that are usually found in the form of air, I come to those that are generally in a fluid form, beginning with water, which is the principal, if not the only cause of fluidity to all the other substances that I shall place in this class. ”

“ This fluid may possibly be the same with that which attracted by and entering into other more solid matter, dilates the substance, by separating the constituent particles and so rendering some solids fluid, and maintaining the fluidity of others; of which fluid when our bodies are totally deprived, they are said to be frozen; when they have a proper quantity they are in health, and fit to perform all their functions ”

“ The fluid, which is propagated hence through one class of nerves, returns in an altered state through another, and the nature of that fluid is spiritual, though not immaterial, any more than, as I before remarked, light or electricity are so. ”

“ We will now consider the stability of a fluid enclosed in a rigid envelop which is non-conducting to heat and impermeable to all the components of the fluid. The fluid is supposed initially homogeneous in the sense in which we have before used the word, i.e., uniform in every respect throughout its whole extent. Let be the ultimate components of the fluid; we may then consider every body which can be formed out of the fluid to be composed of , and that in only one way. Let denote the quantities of these substances in any such body, and let , denote its energy, entropy, and volume. ”

“ Conjunction of the same parts when the same Body shall be made Liquid and Fluid: for if, for example, I take a Mass of Silver or other Solid and hard Mettall, I shall in dividing it into two parts, find not only the resistance that is found in the moving of it only, but an other incomparably greater, dependent on that Great difference betwixt the Conjunction of the parts of a Body when Solid, and when fluid. ”

“ We know that a body submerged in a fluid experiences, when in motion, considerable resistance, but this is because our fluids are viscous; in an ideal fluid, perfectly free from viscosity, the body would stir up behind it a liquid hill, a sort of wake ”

“ Persons hesitate, vacillate, waver; feelings fluctuate or vary. Compare SHAKE.
Antonyms: FLUID. Synonyms:
A fluid is a substance that, like air or water, yields to any force that tends to change its form; a liquid is a body in that state in which the particles move freely among themselves, but remain in one mass, keeping the same volume, but taking always the form of the containing vessel; a liquid is an inelastic fluid; a gas is an elastic fluid that tends to expand to the utmost limits of the containing space. All liquids are fluids, but not all fluids are liquids ”

“ B. Yes; fluids, generally speaking, are bodies of less density than solids. From the slight cohesion, of the particles of fluids, and the facility with which they slide over each other, it is inferred, that they have but a slight attraction for each other, and that this attraction is equal, in every position of their particles, and therefore produces no resistance to a perfect freedom of motion among themselves.
Caroline. Pray what is the distinction between a fluid and a liquid?
Mrs. B. Liquids comprehend only one class of fluids. ”

“ With regard to the power which sets bounds to the expansion of the fluid acting as heat, it is natural to think that it can be no other than the same fluid acting in a contrary direction, or from a circumference towards a centre; and thus we shall always find that the same fluid, by limiting its own operations, may produce those phenomena which have been hitherto deemed so difficult of explanation. ”

“ How should such a fluid get the better of another concocted under the influence of a heat so fostering, of vessels so elaborate, and endowed with such vital energy?—how should such a fluid as the male semen be made to play the part of mere matter?—But of these things more hereafter. ”

“ Under the pressure in these minute vessels, fluid matter oozes through their walls and bathes all the neighbouring tissues. This fluid holds in solution the matters needed for nourishing the tissues, and it also contains gases in solution. Thus the fluid is both a nutritive and respiratory medium; by it the tissues are nourished, and by it they breathe. ”

“ That the water, and such other fluid bodies, are nothing but a congeries of particles agitated or made fluid by it in the same manner as the particles of Salt are agitated or made fluid by a parcel of water, in which they are dissolv'd, and subsiding to the bottom of it, constitute a fluid body, much more massie and dense, and less fluid then the pure water it self.
That the air on the other side is a certain company of particles of quite another kind, that is, such as are very much smaller, and more easiely moveable by the motion of this fluid medium ”

“ Fluid. A form of matter, in which its particles readily flow, or slide, over each other. Airs, or gases, are called elastic fluids, because they are readily reduced to a smaller bulk by pressure. Liquids, are denominated non-elastic fluids, because they suffer but little diminution of bulk, by any mechanical force.
Focus. That point in which converging rays unite.
Force. That power which acts upon a body, either tending to create, or to stop motion.
Fountain. A jet, or stream of water, forced upwards by the weight of other water, by the elasticity of air, or some other mechanical pressure. ”

“ Again, if we suppose the solid matter of the body to remain without variation in quantity or position, it will easily appear that the potentials for the substances which form the fluid components of the solid body must satisfy the same conditions in the solid body and in the fluids in contact with it, as in the case of entirely fluid masses. ”

“ For seeing that a body may be included either with a fluid only, or only with a solid, or partly with a fluid, and partly with a solid, or partly with one fluid, and partly with another; there will be found a very great variety of the terminating surfaces, much differing from a Spherical, according to the various resistance or pressure that belongs to each of these encompassing bodies. ”

“ Wherefore a fluid body is always divisible into bodies equally fluid, as quantity into quantities; and soft bodies, of whatsoever degree of softness, into soft bodies of the same degree. And though many men seem to conceive no other difference of fluidity, but such as ariseth from the different magnitudes of the parts, in which sense dust, though of diamonds, may be called fluid; yet I understand by fluidity, that which is made such by nature equally in every part of the fluid body; not as dust is fluid, for so a house which is falling in pieces may be called fluid ”

“ Bodies swimming upon fluids, when they move straight forward, cause the fluid to ascend at their fore parts and subside at their hinder parts, especially if they are of an obtuse figure; and thence they meet with a little more resistance than if they were acute at the head and tail. And bodies moving in elastic fluids, if they are obtuse behind and before, condense the fluid a little more at their fore parts, and relax the same at their hinder parts; and therefore meet also with a little more resistance than if they were acute at the head and tail. ”

“ For when I have collected an elastic fluid, and observe concerning it that its expansive power is increased by heat and diminished by cold, while it still uniformly retains its elastic fluidity, but also discover in it properties and behaviour different from those of common air, then I consider myself justified in believing that this is a peculiar kind of air. ”

“ He watched as the fluid he had poured emerged into glass tubing no thicker than a human hair, and, under the tons per square inch pressure, stretched into fine fluid columns less than half a dozen molecules thick. ”

“ In tracing the phenomena of sensation and volition to their cause, it is clear that we must call in some peculiar and hyperphysical principle. The hypothesis of a fluid is not made more satisfactory by attenuating the fluid; it becomes subtle, spirituous, ethereal, imponderable, to no purpose; it must cease to be a fluid, before its motions can become sensation and volition. This, indeed, is acknowledged by most physiologists ”

“ That a Body, immersed in a Fluid, sustains a Lateral pressure from the Fluid; and that increased, as the depth of the immersed Body, beneath the Surface of the Fluid, increaseth.
8. That Water may be made as well to depress a Body lighter than it self, as to buoy it up. ”

“ It is possible, in the nature of things, for us to conceive that the fluid which we call water may be produced from other constituents than oxygen or hydrogen, or that such a fluid may even now exist undiscovered, the product of elements altogether unknown. ”

“ Every thing, throughout the whole area of the universe, however ponderous or substantial, however complex or varied, was not merely evolved from the liquid laboratory, but was actually part and parcel of the radical fluid itself. ”

“ The other properties of fluids, such as their inertia, weight, and elasticity, are not attributed to them by those who have used the theory for merely mathematical purposes; but the use of the word Fluid has been apt to mislead the vulgar, including many men of science who are not natural philosophers, and who have seized on the word Fluid as the only term in the statement of the theory which seemed intelligible to them. ”

“ For this it will be necessary to consider the variations of the energy of the fluids only so far as they are immediately connected with the changes in the solid. We may suppose the solid with so much of the fluid as is in close proximity to it to be enclosed in a fixed envelop, which is impermeable to matter and to heat, and to which the solid is firmly attached wherever they meet. ”

“ When a fluid exists in the form of a thin film between other fluids, the great inequality of its extension in different directions will give rise to certain peculiar properties, even when its thickness is sufficient for its interior to have the properties of matter in mass. ”

“ When the fluid parts have been much dissipated, or when we have taken, by the mouth, any dry food, or acrid substance, we experience a sensation of heat in the fauces, and at the same time a great desire of swallowing liquids. ”

“ There are three physical states or conditions of matter, which are the solid, liquid and gaseous, which in this connection apply to Ice, Water and Steam. A solid offers resistance both to change of shape and to change of bulk.
A Fluid offers no resistance to change of shape. Again fluids can be divided into liquids and vapors or gases. Water is the most familiar example of a liquid. A liquid can be poured out in drops while a gas or vapor flows in a stream or streams. ”

“ We have now dignified the blood with the title of the innate heat; with like propriety, we believe, that the fluid which we have called the crystalline colliquament, from which the fœtus and its parts primarily and immediately arise, may be designated the radical and primigenial moisture. There is certainly nothing in the generation of animals to which this title can with better right be given. ”

“ The fluidity of air invests it, as it invests all other liquids, with the power of transmitting pressure; fluidity is a necessary consequence of the independent gravitation of the particles of a fluid. ”

“ Mechanical effects of fluids on animals immersed in them.—When a body is immersed in any fluid whatever, it will lose as much of its weight relatively as is equal to the weight of the fluid it displaces. ”

“ Whether those which have been termed Imponderable Fluids,—the supposed fluids which produce the phenomena of Light, Heat, Electricity, Galvanism, Magnetism,—really exist or no, is a question, not merely of the Laws, but of the Causes of Phenomena. ”

“ The gaseous fluid with which we have chiefly to do is our atmosphere. Though practically invisible, it appeals in its properties to other of our senses, so that the evidences of its presence are manifold. ”

“ The small waves of a liquid, and the undulations of the air, like waves in the corn, are evidently not real masses moving in the direction in which they are advancing, but merely outlines, motions, or forms passing along, and comprehending all the particles of an undulating fluid which are at once in a 131vibratory state. ”

“ Being also fluid, and in perpetual agitation, its parts are constantly mixed together; so that, instead of its heat being all accumulated in its surface, as in the case of a solid opaque body, it is diffused through its whole mass. ”

“ Solid substances are those whose parts firmly cohere and resist impression, as wood or stone. Liquids have free motion among their parts, and easily yield to impression, as water and wine. Aeriform substances are elastic fluids, called vapors and gases, as air and oxygen gas. ”

“ When heat passes in any thermodynamic experiment between the fluid principally considered and some other body, it is actually absorbed and given out by the walls of the vessel, which will retain a varying quantity. ”