Pressure Quotes (17 quotes)
'Tis evident, that as common Air when reduc'd to half Its wonted extent, obtained near about twice as forcible a Spring as it had before; so this thus- comprest Air being further thrust into half this narrow room, obtained thereby a Spring about as strong again as that It last had, and consequently four times as strong as that of the common Air. And there is no cause to doubt, that If we had been here furnisht with a greater quantity of Quicksilver and a very long Tube, we might by a further compression of the included Air have made It counter-balance 'the pressure' of a far taller and heavier Cylinder of Mercury. For no man perhaps yet knows how near to an infinite compression the Air may be capable of, If the compressing force be competently increast.
A Defense of the Doctrine Touching the Spring and Weight of the Air (1662), 62.
Question: State the relations existing between the pressure, temperature, and density of a given gas. How is it proved that when a gas expands its temperature is diminished?
Answer: Now the answer to the first part of this question is, that the square root of the pressure increases, the square root of the density decreases, and the absolute temperature remains about the same; but as to the last part of the question about a gas expanding when its temperature is diminished, I expect I am intended to say I don't believe a word of it, for a bladder in front of a fire expands, but its temperature is not at all diminished.
Answer: Now the answer to the first part of this question is, that the square root of the pressure increases, the square root of the density decreases, and the absolute temperature remains about the same; but as to the last part of the question about a gas expanding when its temperature is diminished, I expect I am intended to say I don't believe a word of it, for a bladder in front of a fire expands, but its temperature is not at all diminished.
Genuine student answer* to an Acoustics, Light and Heat paper (1880), Science and Art Department, South Kensington, London, collected by Prof. Oliver Lodge. Quoted in Henry B. Wheatley, Literary Blunders (1893), 175, Question 1. (*From a collection in which Answers are not given verbatim et literatim, and some instances may combine several students' blunders.)
Formula for breakthroughs in research: Take young researchers, put them together in virtual seclusion, give them an unprecedented degree of freedom and turn up the pressure by fostering competitiveness.
In James Beasley Simpson, Simpson's Contemporary Quotations (1988), 145.
Harvard Law: Under the most rigorously controlled conditions of pressure, temperature, humidity, and other variables, the organism will do as it damn well pleases.
The Coevolution Quarterly, Nos. 8-12 (1975), 138.
How then did we come to the “standard model”? And how has it supplanted other theories, like the steady state model? It is a tribute to the essential objectivity of modern astrophysics that this consensus has been brought about, not by shifts in philosophical preference or by the influence of astrophysical mandarins, but by the pressure of empirical data.
In The First Three Minutes: A Modern View of the Origin of the Universe (1977), 9.
I have been branded with folly and madness for attempting what the world calls impossibilities, and even from the great engineer, the late James Watt, who said ... that I deserved hanging for bringing into use the high-pressure engine. This has so far been my reward from the public; but should this be all, I shall be satisfied by the great secret pleasure and laudable pride that I feel in my own breast from having been the instrument of bringing forward new principles and new arrangements of boundless value to my country, and however much I may be straitened in pecuniary circumstances, the great honour of being a useful subject can never be taken from me, which far exceeds riches.
From letter to Davies Gilbert, written a few months before Trevithick's last illness. Quoted in Francis Trevithick, Life of Richard Trevithick: With an Account of his Inventions (1872), Vol. 2, 395-6.
It would be possible to describe absolutely everything scientifically, but it would make no sense. It would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure.
Attributed to Einstein by Frau Born. Paraphrased words as given in Ronald William Clark, Einstein (1984), 243.
It's only through honesty and courage that science can work at all. The Ptolemaic understanding of the solar system was undermined and corrected by the constant pressure of more and more honest reporting.
In essay, 'The Origin of the Universe,' 6. Written after hearing Stephen Hawking's lecture (2006) at Oxford, about the origin of the universe.
One summer day, while I was walking along the country road on the farm where I was born, a section of the stone wall opposite me, and not more than three or four yards distant, suddenly fell down. Amid the general stillness and immobility about me the effect was quite startling. ... It was the sudden summing up of half a century or more of atomic changes in the material of the wall. A grain or two of sand yielded to the pressure of long years, and gravity did the rest.
Under the Apple-Trees (1916), 105.
Our atom of carbon enters the leaf, colliding with other innumerable (but here useless) molecules of nitrogen and oxygen. It adheres to a large and complicated molecule that activates it, and simultaneously receives the decisive message from the sky, in the flashing form of a packet of solar light; in an instant, like an insect caught by a spider, it is separated from its oxygen, combined with hydrogen and (one thinks) phosphous, and finally inserted in a chain, whether long or short does not matter, but it is the chain of life. All this happens swiftly, in silence, at the temperature and pressure of the atmosphere, and gratis: dear colleagues, when we learn to do likewise we will be sicut Deus [like God], and we will have also solved the problem of hunger in the world.
Levi Primo and Raymond Rosenthal (trans.), The Periodic Table (1975, 1984), 227-228. In this final section of his book, Levi imagines the life of a carbon atom. He calls this his first “literary dream”. It came to him at Auschwitz.
Pressure, no doubt, has always been a most important factor in the metamorphism of rocks; but there is, I think, at present some danger in over-estimating this, and representing a partial statement of truth as the whole truth. Geology, like many human beings, suffered from convulsions in its infancy; now, in its later years, I apprehend an attack of pressure on the brain.
'The Foundation-Stones of the Earth's Crust', Nature, 1888, 39, 93.
So many of the properties of matter, especially when in the gaseous form, can be deduced from the hypothesis that their minute parts are in rapid motion, the velocity increasing with the temperature, that the precise nature of this motion becomes a subject of rational curiosity. Daniel Bernoulli, Herapath, Joule, Kronig, Clausius, &c., have shewn that the relations between pressure, temperature and density in a perfect gas can be explained by supposing the particles move with uniform velocity in straight lines, striking against the sides of the containing vessel and thus producing pressure. (1860)
In W.D. Niven (ed.) 'Illustrations of the Dynamical Theory of Gases,' The Scientific Papers of James Clerk Maxwell, Vol 1, 377. Quoted in John David Anderson, Jr., Hypersonic and High Temperature Gas Dynamics (2000), 468.
That there is a Spring, or Elastical power in the Air we live in. By which ελατνρ [elater] or Spring of the Air, that which I mean is this: That our Air either consists of, or at least abounds with, parts of such a nature, that in case they be bent or compress'd by the weight of the incumbent part of the Atmosphere, or by any other Body, they do endeavour, as much as in them lies, to free themselves from that pressure, by bearing against the contiguous Bodies that keep them bent.
New Experiments Physico-Mechanical Touching the Spring of the Air (1660), 22.
The results have exhibited one striking feature which has been frequently emphasized, namely that at high pressures all twelve liquids become more nearly like each other. This suggests that it might be useful in developing a theory of liquids to arbitrarily construct a 'perfect liquid' and to discuss its properties. Certainly the conception of a 'perfect gas' has been of great service in the kinetic theory of gases; and the reason is that all actual gases approximate closely to the 'perfect gas.' In the same way, at high pressures all liquids approximate to one and the same thing, which may be called by analogy the 'perfect liquid.' It seems to offer at least a promising line of attack to discuss the properties of this 'perfect liquid,' and then to invent the simplest possible mechanism to explain them.
'Thermodynamic Properties of Twelve Liquids Between 200 and 800 and up to 1200 KGM. Per Sq. Cm.', Memoirs of the American Academy of Arts and Sciences, 1913, 49, 113.
The theory here developed is that mega-evolution normally occurs among small populations that become preadaptive and evolve continuously (without saltation, but at exceptionally rapid rates) to radically different ecological positions. The typical pattern involved is probably this: A large population is fragmented into numerous small isolated lines of descent. Within these, inadaptive differentiation and random fixation of mutations occur. Among many such inadaptive lines one or a few are preadaptive, i.e., some of their characters tend to fit them for available ecological stations quite different from those occupied by their immediate ancestors. Such groups are subjected to strong selection pressure and evolve rapidly in the further direction of adaptation to the new status. The very few lines that successfully achieve this perfected adaptation then become abundant and expand widely, at the same time becoming differentiated and specialized on lower levels within the broad new ecological zone.
Tempo and Mode in Evolution (1944), 123.
The wintry clouds drop spangles on the mountains. If the thing occurred once in a century historians would chronicle and poets would sing of the event; but Nature, prodigal of beauty, rains down her hexagonal ice-stars year by year, forming layers yards in thickness. The summer sun thaws and partially consolidates the mass. Each winter's fall is covered by that of the ensuing one, and thus the snow layer of each year has to sustain an annually augmented weight. It is more and more compacted by the pressure, and ends by being converted into the ice of a true glacier, which stretches its frozen tongue far down beyond the limits of perpetual snow. The glaciers move, and through valleys they move like rivers.
The Glaciers of the Alps & Mountaineering in 1861 (1911), 247.
There exists for every liquid a temperature at which no amount of pressure is sufficient to retain it in the liquid form.
[These words are NOT by Thomas Andrews. See below.]
[These words are NOT by Thomas Andrews. See below.]
This is NOT a quote by Andrews. It is only included here to provide this caution, because at least one book attributes it incorrectly to Andrews, as in John Daintith, Biographical Encyclopedia of Scientists (3rd. ed., 2008), 19. Webmaster has determined that these words are those of William Allen Miller, in Elements of Chemistry (1855), Vol. 1, 257. In the article on Thomas Andrews in Charles Coulston Gillespie (ed.), Dictionary of Scientific Biography (1970), Vol. 1, 161, the later, third edition (1863) of Miller's textbook is named as the first printed account of Andrews' work. (Andrews had furnished his experimental results to Miller by letter.) After stating Miller's description of Andrews' results, the article in DSB refers ambiguously to “his” summary and gives the quote above. No quotation marks are present in Miller's book. Specifically, in fact, the words in the summary are by Miller. This is seen in the original textbook, because Miller prefaced the quote with “From these experiments it is obvious that...” and is summarizing the related work of several scientists, not just Andrews. Miller described the earlier experiments of those other researchers in the immediately preceding pages. It is clear that the quote does not come from Andrews when comparing Miller's first edition (1855), which had not yet included the work by Andrews. Thus, the same summary words (as quoted above) in the earliest edition refer to the experiments of only the other researchers, not including Andrews. Furthermore, the quote is not present in the Bakerian Lecture by Andrews on his work, later published in Philosophical Transactions of the Royal Society (1869). Webmaster speculates Daintith's book was written relying on a misreading of the ambiguous sentence in DSB.
At the heart of science is an essential balance between two seemingly contradictory attitudes--an openness to new ideas, no matter how bizarre or counterintuitive they may be, and the most ruthless skeptical scrutiny of all ideas, old and new. This is how deep truths are winnowed from deep nonsense. -- Carl Sagan
