Steam engine

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Model beam engine with James Watt's double action parallel linkage.

A steam engine is a heat engine that performs mechanical work using steam as its working fluid.

CONTENT : A - F , G - L , M - R , S - Z , See also , External links


Quotes are arranged alphabetically by author

A - F[edit]

  • Iron and heat are, as we know, the supporters, the bases, of the mechanic arts. It is doubtful if there be in England a single industrial establishment of which the existence does not depend on the use of these agents, and which does not freely employ them. To take away to-day from England her steam-engines would be to take away at the same time her coal and iron. It would be to dry up all her sources of wealth, to ruin all on which her prosperity depends, in short, to annihilate that colossal power. The destruction of her navy, which she considers her strongest defence, would perhaps be less fatal.
  • A blacksmith, Thomas Newcomen, in collaboration with a plumber, John Calley, produced the first commercially successful machine for "raising water by fire." Newcomen could not have based his design on prevailing scientific theory, White argued, because his engine relied on the dissolution of air in steam, and "scientists in his day were not aware that air dissolves in water." Evidently "the mastery of steam power" was a product of empirical science and was "not influenced by Galilean science."
    • Clifford D. Conner, A People's History of Science (2005) quoting from Lynn White, Jr., "Pumps and Pendula: Galileo and Technology," in Galileo Reappraised ed. Carlo Luigi Golino (1966)
  • The industrial revolution was well underway before the steam-engine came into use for driving machinery. Only two prime-movers—the water wheel and the windmill—were widely available, and with very few exceptions these yielded no more than 10 h.p. and often less.
    • T. K. Derry & Trevor I. Williams, A Short History of Technology: From the Earliest Times to A.D. 1900 (1960) Ch.11, The Steam Engine

G - L[edit]

Newcomen's atmospheric
steam engine.
  • Newcomen's invention was radically different from that of Savery or any other single person. Papin invented the cylinder and piston as a means for transforming energy into motion. At first he used the explosive force of gunpowder, and later the use of the expansive force of steam, to raise the piston, and then by removing the fire to cause it to fall again. He made no further use of this principle. Savery discovered that the sudden condensation of steam made a vacuum that he utilized to draw up water. His pumps were actually used to drain mines, but were never satisfactory. They had to be placed within the mine to be drained, not over forty feet from the bottom, and then could be used to force up water an additional height of perhaps 100 feet. Beyond this the process must be repeated. It will be noticed that the water to be forced came into direct contact with the steam, which was contained in a solid vessel.
    In addition tremendous pressures were necessary: as high as 1,200 pounds per square inch were secured, and with the materials for construction at hand frequent and disastrous explosions were the result.
    Newcomen used Papin's cylinder and piston, and Savery's principle of the condensation of steam to produce a vacuum. But unlike Papin he used the expansive force of steam to do his work, and unlike Savery he used a cylinder and piston actuated by alternate expansion and condensation of steam to transform heat into mechanical motion.
  • At first [Newcomen] made a double cylinder, using the space between for condensing water. This was not very satisfactory. The vacuum was secured very slowly and imperfectly. In 1711 they attempted to erect an engine for draining a mine, but failed. The next year they succeeded... but it was slow and ineffective. To operate it, required two men and a boy. The boy's work was to alternately open and close the valves to the condensing water and to the boiler. One day the engine made two or three motions quickly and powerfully. Newcomen immediately examined the cylinder and found a small hole, through which a small jet from the water that was on top of the piston to make it steam tight, was spurting into the cylinder. He appreciated the significance... [and] dispensed with the outer water jacket and injected the water for condensation, through a small pipe in the bottom of the cylinder. It... increased the speed of the engine from eight to fifteen strokes a minute, besides getting the advantage of a good vacuum.
    In 1713 a pump was erected in Leeds, and the boy who was hired to open and shut the valves, in an effort to make his work easier, rigged up a contrivance of strings and levers that operated the valves from the motion of the working beam over head. This made the engine automatic and marked another stage in its evolution. This boy, Humphrey Potter... This valve motion was afterward improved by Henry Beighton in 1718. This engine... continued to be until the days of Watt...
  • If the Steam Engine be the most powerful instrument in the hands of man, to alter the face of the physical world, it operates, at the same time, as a powerful moral lever in forwarding the great cause of civilization. ...the discovery of Mr. Watt... subdued and regulated the most terrific power in the universe,—that power which, by the joint operation of pressure and heat... This apparently ungovernable power Mr. Watt reduced to a state of such perfect organization and discipline... that it may now be safely manœuvred and brought into irresistible action... at the will of man, and under the guidance of his feeble hand. Thus one man directs it into the bowels of the earth, to tear asunder its very elements, and bring to light its hidden treasures; another places it upon the surface of the waters, to control the winds of heaven, to stem the tides, to check the currents, and defy the waves of the ocean; a third, perhaps and a fourth, are destined to apply this mighty power to other purposes, still unthought of and unsuspected, but leading to consequences, possibly not less important than those which it has already produced. ... those benefits, conferred by Mr. Watt on the whole civilized world, have been most experienced by his own country, which owes a tribute of national gratitude to a man, who has thus honoured her by his genius, and promoted her well being by his discoveries.

M - R[edit]

  • Dr. Denys Papin, a native of Blois, a man of great ingenuity, and of considerable acquirements as a philosopher, is considered by his countrymen to be the true inventor of the Steam Engine: a claim strongly contested by some English authors of eminence who have written on the subject,—but on grounds which appear to have been taken from very erroneous and prejudiced statements. It is due to Papin, to state, that no one, whose labours have produced so many important results, has in his writings shewn so little of the vanity and absurd enthusiasm proverbially characteristic of an inventor.
  • My first essay at making a steam engine was when I was fifteen. I then made a real working; steam-engine, 1 3/4 diameter cylinder, and 8 in. stroke, which not only could act, but really did some useful work; for I made it grind the oil colours which my father required for his painting. Steam engine models, now so common, were exceedingly scarce in those days, and very difficult to be had; and as the demand for them arose, I found it both delightful and profitable to make them; as well as sectional models of steam engines, which I introduced for the purpose of exhibiting the movements of all the parts, both exterior and interior...
  • I have endeavoured to attain this end (viz. the production of a vacuum in the cylinder) in another way. As water has the property of elasticity, when converted into steam by heat, and afterwards of being so completely recondensed by cold, that there does not remain the least appearance of this elasticity, I have thought that it would not be difficult to work machines in which, by means of a moderate heat and at a small cost, water might produce that perfect vacuum which has vainly been sought by means of gunpowder.
    • Denis Papin, Recueil de diverses Pièces touchant quelques nouvelles Machines (1695) p. 53 as quoted by Dionysius Lardner, The Steam Engine Explained and Illustrated (1840) pp. 45-46
  • Turning a small surface of water into vapour by fire, applied to the bottom of the cylinder that contains it; which vapour forces up the plug (or piston) in the cylinder to a considerable height, and which, as the vapour condenses, (as the water cools when taken from the fire,) descends again by air's pressure, and is applied to raise water out of the mine.
    • Denis Papin, Letter, as quoted by Robert Stuart Meikleham, A Descriptive History of the Steam Engine (1824)
  • What I say here is not to give room for believing, that Mr. Savery, who has since published this invention at London, is not actually the inventor. I do not doubt that the same thought may have occurred to him, as well as to others, without having learnt it elsewhere.
  • Present day knowledge of both the theory and the technique of steam engines has justified Watt in the principles which he laid down, which were that the greater the steam pressure and range of expansion, the greater will be the work obtained from a given weight of steam, and that the cylinder should be kept as hot as the steam which enters it. The main development of the steam engine since his time has consisted in an extension of the range of expansion and in an ever increasing degree of compounding. The separation of the condenser from the cylinder by Watt was followed by the division of the expansion into stages in separate cylinders, finally into four stages in the highest development of the reciprocating engine. The steam turbine carries this subdivision still further, the number of stages included in a reaction turbine of high efficiency being commonly sixty or more.
    • Sir Charles A. Parsons: "The steam turbine". Proceedings of the International Congress of Mathematicians in Toronto, August 11–16. 1924. II. pp. 465–472.  (p. 465)

S - Z[edit]

Thomas Savery's 'Miner's Friend' steeam-driven water pump (1699)
  • Should the engine, to the apprehension of some, seem intricate and difficult to be worked, after all the description I have given of it in this book, yet I can, and do assure them, that the attending and working the engine is so far from being so, that it is familiar and easy to be learned by those of the meanest capacity, in a very little time; insomuch that I have boys of thirteen or fourteen years of age, who now attend and work it to perfection, and were taught to do it in a few days; and I have known some learn to work the engine in half an hour. We have a proverb, that interest never lies; and I am assured that you gentlemen of the mines and collieries, when you have once made this engine familiar in your works, and to yourselves and servants; not only the profit, but abundance of other advantages and conveniences which you will find to attend your works in the use thereof, will create in you a favourable opinion of the labours of
    Your real Friend and humble Servant,
  • I only just hint this to show what use this engine may be put to in working of mills, especially where coals are cheap. I have only this to urge, that water in its fall from any determinate height, has simply a force answerable and equal to the force that raises it.
  • Amongst the several Engines which have been contriv'd for the raising of Water for the Supply of Houses and Gardens, none has been more justly surprising, than that for the raising of Water by Fire; the particular Contrivance and sole Invention of a Gentleman, with whom I had the Honour long since to be well acquainted; I mean, the ingenious Captain Savery, sometime since deceased, but then a most noted engineer, and one of the Commissioners of the Sick and Wounded. ...It was a considerable Time before this curious Person, who has been so great an Honour to his Country, could, (as he himself tells us) bring this his Design to Perfection, on account of the Aukwardness of the Workmen, who were necessarily to be imploy'd in the Affair; but at last he conquer'd all Difficulties, and procur'd a Recommendation of it from the Royal Society, in Transac. No. 252. and soon after, a Patent from the Crown, for the sole making this Engine; And I have heard him say my self, that the very first Time he play'd it, it was in a Potter's House at Lambeth, where, tho' it was a small Engine, yet it forc'd its Way thro' the Roof, and struck up the Tiles in a Manner that Surpris'd all the Spectators.
  • The first machine of Papin was very similar to the gunpowder-engine... of Huyghens. In place of gunpowder, a small quantity of water is placed at the bottom of the cylinder, A; a fire is built beneath it, "the bottom being made of very thin metal," and the steam formed soon raises the piston, B, to the top where a latch, E, engaging a notch in latch engaging the piston rod, H, holds it up until it is desired that it shall drop. The fire being removed, the steam condenses, and a vacuum is formed below the piston, and the latch, E, being disengaged, the piston is driven down by the superincumbent atmosphere and raises the weight which has been, meantime, attached to a rope... passing from the piston rod over pulleys... The machine had a cylinder two and a half inches in diameter, and raised 60 pounds once a minute; and Papin calculated that a machine of a little more than two feet diameter of cylinder and of four feet stroke would raise 8,000 pounds four feet per minute—i.e., that it would yield about one horse-power.
Thomas Savery's 'Miner's Friend' steam-driven water pump
Fig.2 from Thomas Tredgold,
The Steam Engine..
  • In June, 1699, Captain Savery exhibited a model of his engine before the Royal Society, and the experiments he made with it succeeded to their satisfaction. It consisted of a furnace and boiler B: from the latter, two pipes, provided with cocks C, proceeded to two steam vessels S, which had branch pipes from a descending main D, and also to a rising main pipe A: each pair of branch pipes had [check] valves a, b to prevent the descent of the water raised by the condensation or by the force of steam. Only one vessel, S, is shown, the other being immediately behind it. One of the steam vessels being filled with steam, condensation was produced by projecting cold water, from a small cistern E, against the vessel; and into the partial vacuum made by that means, the water, by the pressure of the atmosphere, was forced up the descending main D, from a depth of about twenty feet; and on the steam being let into the vessels again, the valve b closed, and prevented the descent of the water, while the steam having acquired force in the boiler, its pressure caused the water to raise the valve a, and ascend to a height proportional to the excess of the elastic force of the steam above the pressure of the air.
  • About the year 1761, or 1762, I tried some experiments on the force of steam in a Papin's digester, and formed a species of steam-engine by fixing upon it a syringe, one-third of an inch diameter, with a solid piston, and furnished also with a cock to admit the steam from the digester, or shut it off at pleasure, as well as to open a communication from the inside of the syringe to the open air, by which the steam contained in the syringe might escape. When the communication between the digester and syringe was opened, the steam entered the syringe, and by its action upon the piston raised a considerable weight (15 lbs.) with which it was loaded. When this was raised as high as was thought proper, the communication with the digester was shut, and that with the atmosphere opened; the steam then made its escape, and the weight descended. The operations were repeated, and, though in this experiment the cock was turned by hand, it was easy to see how it could be done by the machine itself, and to make it work with perfect regularity. But I soon relinquished the idea of constructing an engine upon its principle, from being sensible it would be liable to some of the objections against Savery's engine, viz., the danger of bursting the boiler, and the difficulty of making the joints tight, and also that a great part of the power of the steam would be lost, because no vacuum was formed to assist the descent of the piston. I, however, described this engine in the fourth article of the specification of my patent of 1769; and again in the specification of another patent in the year 1784, together with a mode of applying it to the moving of wheel-carriages.
    • James Watt, "Notes on Professor Robison's Dissertation on Steam-engines" (1769) from Robison's Essays on Various Subjects of Mechanical Philosophy (1822) ed. David Brewster Vol. 2, p. 347
  • When once the idea of the separate condensation was started, all these improvements followed as corollaries in quick succession, so that in the course of one or two days the invention was thus far complete in my mind, and I immediately set about an experiment to verify it practically.
    • James Watt, "Notes on Professor Robison's Dissertation on Steam-engines" (1769) from Robison's Essays on Various Subjects of Mechanical Philosophy (1822) ed. David Brewster Vol. 2, p. 347

See also[edit]

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