A History of the Growth of the Steam-Engine.

by Robert H. Thurston.

PREFACE.

This little work embodies the more generally interesting portions of lectures first written for delivery at the STEVENS INSt.i.tUTE OF TECHNOLOGY, in the winter of 1871-"72, to a mixed audience, composed, however, princ.i.p.ally of engineers by profession, and of mechanics; it comprises, also, some material prepared for other occasions.

These lectures have been rewritten and considerably extended, and have been given a form which is more appropriate to this method of presentation of the subject. The account of the gradual development of the philosophy of the steam-engine has been extended and considerably changed, both in arrangement and in method. That part in which the direction of improvement during the past history of the steam-engine, the course which it is to-day taking, and the direction and limitation of that improvement in the future, are traced, has been somewhat modified to accord with the character of the revised work.

The author has consulted a large number of authors in the course of his work, and is very greatly indebted to several earlier writers. Of these, Stuart[1] is ent.i.tled to particular mention. His "History" is the earliest deserving the name; and his "Anecdotes" are of exceedingly great interest and of equally great historical value. The artistic and curious little sketches at the end of each chapter are from John Stuart, as are, usually, the drawings of the older forms of engines.

[1] "History of the Steam-Engine," London, 1824. "Anecdotes of the Steam-Engine," London, 1829.

Greenwood"s excellent translation of Hero, as edited by Bennett Woodcroft (London, 1851), can be consulted by those who are curious to learn more of that interesting old Greek treatise.

Some valuable matter is from Farey,[2] who gives the most extended account extant of Newcomen"s and Watt"s engines. The reader who desires to know more of the life of Worcester, and more of the details of his work, will find in the very complete biography of Dircks[3] all that he can wish to learn of that great but unfortunate inventor.

Smiles"s admirably written biography of Watt[4] gives an equally interesting and complete account of the great mechanic and of his partners; and Muirhead[5] furnishes us with a still more detailed account of his inventions.

[2] "Treatise on the Steam-Engine," London, 1827.

[3] "Life, Times, and Scientific Labors of the Second Marquis of Worcester," London, 1865.

[4] "Lives of Boulton and Watt," London, 1865.

[5] "Life of James Watt," D. Appleton & Co., New York, 1859.

"Mechanical Inventions of James Watt," London, 1854.

For an account of the life and work of John Elder, the great pioneer in the introduction of the now standard double-cylinder, or "compound," engine, the student can consult a little biographical sketch by Prof. Rankine, published soon after the death of Elder.

The only published sketch of the history of the science of thermo-dynamics, which plays so large a part of the philosophy of the steam-engine, is that of Prof. Tait--a most valuable monograph.

The section of this work which treats of the causes and the extent of losses of heat in the steam-engine, and of the methods available, or possibly available, to reduce the amount of this now immense waste of heat, is, in some respects, quite new, and is equally novel in the method of its presentation. The portraits with which the book is well furnished are believed to be authentic, and, it is hoped, will lend interest, if not adding to the real value of the work.

Among other works which have been of great a.s.sistance to the author, and will be found, perhaps, equally valuable to some of the readers of this little treatise, are several to which reference has not been made in the text. Among them the following are deserving of special mention: Zeuner"s "Warmetheorie," the treatises of Stewart and of Maxwell, and McCulloch"s "Mechanical Theory of Heat," a short but thoroughly logical and exact mathematical treatise; Cotterill"s "Steam-Engine considered as a Heat-Engine," a more extended work on the same subject, which will be found an excellent companion to, and commentary upon, Rankine"s "Steam-Engine and Prime Movers," which is the standard treatise on the theory of the steam-engine. The works of Bourne, of Holley, of Clarke, and of Forney, are standards on the practical every-day matters of steam-engine construction and management.

The author is almost daily in receipt of inquiries which indicate that the above remarks will be of service to very many young engineers, as well as to many to whom the steam-engine is of interest from a more purely scientific point of view.

["A Machine, receiving at distant times and from many hands new combinations and improvements, and becoming at last of signal benefit to mankind, may be compared to a rivulet swelled in its course by tributary streams, until it rolls along a majestic river, enriching, in its progress, provinces and kingdoms.

"In retracing the current, too, from where it mingles with the ocean, the pretensions of even ample subsidiary streams are merged in our admiration of the master-flood, glorying, as it were, in its expansion. But as we continue to ascend, those waters which, nearer the sea, would have been disregarded as unimportant, begin to rival in magnitude and share our attention with the parent stream; until, at length, on our approaching the fountains of the river, it appears trickling from the rock, or oozing from among the flowers of the valley.

"So, also, in developing the rise of a machine, a coa.r.s.e instrument or a toy may be recognized as the germ of that production of mechanical genius, whose power and usefulness have stimulated our curiosity to mark its changes and to trace its origin. The same feelings of reverential grat.i.tude which attached holiness to the spot whence mighty rivers sprang, also clothed with divinity, and raised altars in honor of, inventors of the saw, the plough, the potter"s wheel, and the loom."--STUART.]

THE GROWTH OF THE STEAM-ENGINE.

CHAPTER I.

_THE STEAM-ENGINE AS A SIMPLE MACHINE._

SECTION I.--THE PERIOD OF SPECULATION--FROM HERO TO WORCESTER, B. C.

200 TO A. D. 1650.

One of the greatest of modern philosophers--the founder of that system of scientific philosophy which traces the processes of evolution in every department, whether physical or intellectual--has devoted a chapter of his "First Principles" of the new system to the consideration of the multiplication of the effects of the various forces, social and other, which are continually modifying this wonderful and mysterious universe of which we form a part. Herbert Spencer, himself an engineer, there traces the wide-spreading, never-ceasing influences of new inventions, of the introduction of new forms of mechanism, and of the growth of industrial organization, with a clearness and a conciseness which are so eminently characteristic of his style. His ill.u.s.tration of this idea by reference to the manifold effects of the introduction of steam-power and its latest embodiment, the locomotive-engine, is one of the strongest pa.s.sages in his work.

The power of the steam-engine, and its inconceivable importance as an agent of civilization, has always been a favorite theme with philosophers and historians as well as poets. As Religion has always been, and still is, the great _moral_ agent in civilizing the world, and as Science is the great _intellectual_ promoter of civilization, so the Steam-Engine is, in modern times, the most important _physical_ agent in that great work.

It would be superfluous to attempt to enumerate the benefits which it has conferred upon the human race, for such an enumeration would include an addition to every comfort and the creation of almost every luxury that we now enjoy. The wonderful progress of the present century is, in a very great degree, due to the invention and improvement of the steam-engine, and to the ingenious application of its power to kinds of work that formerly taxed the physical energies of the human race. We cannot examine the methods and processes of any branch of industry without discovering, somewhere, the a.s.sistance and support of this wonderful machine. Relieving mankind from manual toil, it has left to the intellect the privilege of directing the power, formerly absorbed in physical labor, into other and more profitable channels. The intelligence which has thus conquered the powers of Nature, now finds itself free to do head-work; the force formerly utilized in the carrying of water and the hewing of wood, is now expended in the G.o.d-like work of THOUGHT. What, then, can be more interesting than to trace the history of the growth of this wonderful machine?--the greatest among the many great creations of one of G.o.d"s most beneficent gifts to man--the power of invention.

While following the records and traditions which relate to the steam-engine, I propose to call attention to the fact that its history ill.u.s.trates the very important truth: _Great inventions are never, and great discoveries are seldom, the work of any one mind_. Every great invention is really either an aggregation of minor inventions, or the final step of a progression. It is not a creation, but _a growth_--as truly so as is that of the trees in the forest. Hence, the same invention is frequently brought out in several countries, and by several individuals, simultaneously. Frequently an important invention is made before the world is ready to receive it, and the unhappy inventor is taught, by his failure, that it is as unfortunate to be in advance of his age as to be behind it. Inventions only become successful when they are not only needed, but when mankind is so far advanced in intelligence as to appreciate and to express the necessity for them, and to at once make use of them.

More than half a century ago, an able New England writer, in a communication to an English engineering periodical, described the new machinery which was built at Newport, R. I., by John Babc.o.c.k and Robert L. Thurston, for one of the first steamboats that ever ran between that city and New York. He prefaced his description with a frequently-quoted remark to the effect that, as Minerva sprang, mature in mind, in full stature of body, and completely armed, from the head of Jupiter, so the steam-engine came forth, perfect at its birth, from the brain of James Watt. But we shall see, as we examine the records of its history, that, although James Watt was _an_ inventor, and probably the greatest of the inventors of the steam-engine, he was still but one of the many men who have aided in perfecting it, and who have now made us so familiar with it, and its tremendous power and its facile adaptations, that we have almost ceased to admire it, or to wonder at the workings of the still more admirable intelligence that has so far perfected it.

Twenty-one centuries ago, the political power of Greece was broken, although Grecian civilization had risen to its zenith. Rome, ruder than her polished neighbor, was growing continually stronger, and was rapidly gaining territory by absorbing weaker states. Egypt, older in civilization than either Greece or Rome, fell but two centuries later before the a.s.sault of the younger states, and became a Roman province.

Her princ.i.p.al city was at this time Alexandria, founded by the great soldier whose name it bears, when in the full tide of his prosperity.

It had now become a great and prosperous city, the centre of the commerce of the world, the home of students and of learned men, and its population was the wealthiest and most civilized of the then known world.

It is among the relics of that ancient Egyptian civilization that we find the first records in the early history of the steam-engine. In Alexandria, the home of Euclid, the great geometrician, and possibly contemporary with that talented engineer and mathematician, Archimedes, a learned writer, called Hero, produced a ma.n.u.script which he ent.i.tled "Spiritalia seu Pneumatica."

It is quite uncertain whether Hero was the inventor of any number of the contrivances described in his work. It is most probable that the apparatus described are princ.i.p.ally devices which had either been long known, or which were invented by Ctesibius, an inventor who was famous for the number and ingenuity of the hydraulic and pneumatic machines that he devised. Hero states, in his Introduction, his intention to describe existing machines and earlier inventions, and to add his own.

Nothing in the text, however, indicates to whom the several machines are to be ascribed.[6]

[6] The British Museum contains four ma.n.u.script copies of Hero"s "Pneumatics," which were written in the fifteenth and sixteenth centuries. These ma.n.u.scripts have been examined with great care, and a translation from them prepared by Prof. J. G. Greenwood, and published at the desire of Mr. Bennett Woodcroft, the author of a valuable little treatise on "Steam Navigation." This is, so far as the author is aware, the only existing English translation of any portion of Hero"s works.

The first part of Hero"s work is devoted to applications of the syphon. The 11th proposition is the first application of heat to produce motion of fluids.

An altar and its pedestal are hollow and air-tight. A liquid is poured into the pedestal, and a pipe inserted, of which the lower end pa.s.ses beneath the surface of the liquid, and the upper extremity leads through a figure standing at the altar, and terminates in a vessel inverted above this altar. When a fire is made on the altar, the heat produced expands the confined air, and the liquid is driven up the tube, issuing from the vessel in the hand of the figure standing by the altar, which thus seems to be offering a libation. This toy embodies the essential principle of all modern heat-engines--the change of energy from the form known as heat-energy into mechanical energy, or work. It is not at all improbable that this prototype of the modern wonder-working machine may have been known centuries before the time of Hero.

Many forms of hydraulic apparatus, including the hand fire-engine, which is familiar to us, and is still used in many of our smaller cities, are described, the greater number of which are probably attributable to Ctesibius. They demand no description here.

A hot-air engine, however, which is the subject of his 37th proposition, is of real interest.

Hero sketches and describes a method of opening temple-doors by the action of fire on an altar, which is an ingenious device, and contains all the elements of the machine of the Marquis of Worcester, which is generally considered the first real steam-engine, with the single and vital defect that the expanding fluid is air instead of steam. The sketch, from Greenwood"s translation, exhibits the device very plainly. Beneath the temple-doors, in the s.p.a.ce _A B C D_, is placed a spherical vessel, _H_, containing water. A pipe, _F G_, connects the upper part of this sphere with the hollow and air-tight sh.e.l.l of the altar above, _D E_. Another pipe, _K L M_, leads from the bottom of the vessel, _H_, over, in syphon-shape, to the bottom of a suspended bucket, _N X_. The suspending cord is carried over a pulley and led around two vertical barrels, _O P_, turning on pivots at their feet, and carrying the doors above. Ropes led over a pulley, _R_, sustain a counterbalance, _W_.

[Ill.u.s.tration: FIG. 1.--Opening Temple-Doors by Steam, B. C. 200.]

On building a fire on the altar, the heated air within expands, pa.s.ses through the pipe, _F G_, and drives the water contained in the vessel, _H_, through the syphon, _K L M_, into the bucket, _N X_. The weight of the bucket, which then descends, turns the barrels, _O P_, raises the counterbalance, and opens the doors of the temple. On extinguishing the fire, the air is condensed, the water returns through the syphon from the bucket to the sphere, the counterbalance falls, and the doors are closed.