Ericsson's Caloric Engine

Source: Lecture on the late improvements in Steam Navigation and the Art of Naval Welfare, with a brief notice of Ericsson's Caloric Engine, p. 52.
Date: New-York, May 10th, 1844
Author: John O. Sargent

The following Lecture was prepared for the BOSTON LYCEUM, and was delivered before that Association in December last. Its topics have proved of sufficient interest to induce frequent applications for its repetition, which, in consequence of professional engagements, the writer has been compelled in every instance to decline.

He now acquiesces in its publication with reluctance, because it was not originally intended for the press, and must appear with the numerous defects, which in an oral discourse may be readily pardoned, but in the printed page cannot escape censure. The novelty of its materials, however, must compensate, so far as it may, for the rudeness of its execution.

The heat theory adopted by Ericsson and here exposed, contravenes the modern thermodynamic theory, that was, at Ericsson's time, still in its infancy.

Origin of Ericsson's heat theory

ERICSSON's Caloric Engine, which excited so much interest a few years ago in England; and which, if it should be brought into practical operation, will prove the most important mechanical invention ever conceived by the human mind, and one that will confer greater benefits on civilized life than any that has ever preceded it. For the object of it is the production of mechanical power by the agency of heat, at an expenditure of fuel so exceedingly small, that man will have an almost unlimited mechanical force at his command, in regions where fuel may now be said hardly to exist.

The announcement of such an idea may startle all those acquainted with the nature of heat, and the well known limits of the amount of mechanical power which any given quantity of caloric is capable of producing ; more particularly, as it is a well established fact, that a given quantity of heat will exert an equal amount of mechanical power, to whatsoever medium it may be imparted.

Ericsson's theory of heat is altogether in opposition to the received notion, that the mechanical force produced will bear a direct known proportion to the quantity of caloric generated ; and that the power exerted in our best constructed steam-engines is nearly the measure of that effect.

The late professor HARVEFELDT, of Sweden, one of the first mathematicians of the day, stated in a public lecture, not many years ago, that there is nothing in the theory of heat which proves that a common spirit lamp may not be sufficient to drive an engine of an hundred horse power. It will readily be believed that the professor had but few hearers who did not smile at the suggestion ; but among those few we may number ERICSSON, who, from the earliest period of his mechanical labors, had been in the habit of regarding heat as an agent, WHICH, WHILST IT EXERTS MECHANICAL FORCE, UNDERGOES NO CHANGE.

This extraordinary fact, ERICSSON exemplifies, by a simple but conclusive illustration ; for the readier reception of which, by the audience, it will be well to introduce particular dimensions.

Suppose the piston of an ordinary steam-engine cylinder to be at the bottom, and suppose the force of the steam intended to be admitted into this cylinder under the piston to act with the force of 100,000 pounds, which is the force on a piston of 50 inches diameter, acted upon by steam of 50 pounds pressure to the square inch. Suppose the cylinder to be ten feet long, and the piston to be loaded with a weight equal to these 100,000 pounds.
If, now, a sufficient quantity of steam of the stated pressure be admitted from below the piston, this load will be elevated through the whole length of the cylinder ; and hence we shall have raised a weight of 100,000 pounds through a space of ten feet.

But who will contend that this immense amount of mechanical force has required any EXPENDITURE OF HEAT? Does not the steam, after having lifted this weight, contain just as much heat as it did before leaving the steam-boiler less only the losses by radiation ? And does not that heat retain all the properties AFTER the operation which it possessed BEFORE ? Am I, then, incorrect in stating that we have obtained this power without changing the nature, or diminishing the energy of the heat employed ?
But although nature has furnished us with an agent of such extraordinary properties for the production of mechanical force, how imperfectly do we employ it !

In the low-pressure engine we turn the steam, after having performed its good office, into a condensing apparatus where the heat is in a manner annihilated ; and in the high-pressure engine, we throw it away into the atmosphere. Yet men, even of mechanical distinction, ridicule the idea of superseding the steam-engine ; and Science seems to pause contentedly in the contemplation of its admitted perfection. For a mere theorist to attempt an exposition of its defects, or to suggest a substitute would, under such circumstances, excite little attention ; but the opinions and views, in this connection, of a man of great practical knowledge, who has planned and constructed hundreds of steam-engines, are entitled, certainly, to peculiar consideration.

The birth of the Regenerator and the Caloric Engine

From what I have already said, it will be readily inferred that the principle forming the basis of the CALORIC ENGINE is that of returning the heat, at each stroke of the piston, and using it over and over again. This is obviously impracticable, if steam is employed as the acting medium.

ERICSSON, therefore, uses the permanent gases, and, in preference to all others, atmospheric air. The object which he seeks to accomplish is simply this that the heat, contained in the air which escapes from the working cylinder, should be effectually taken up by the air which enters it, at each stroke of the engine.

This result Captain ERICSSON has accomplished by means of an apparatus which he styles a regenerator ; and so perfectly does it operate, that the heat employed in first setting the engine in motion continues to sustain it in full working force, with no other renewal or addition than may be requisite to supply the inconsiderable loss by radiation.

This remarkable invention was first brought before the scientific world in London in the year 1833, though it had been a favorite subject of speculation and reflection with Captain ERICSSON for many years. With the prominent exception of the celebrated Dr. ANDREW URE, and Professor FARAYDAY, now the most distinguished chemists in ENGLAND, nearly all the leading scientific men of the day united in condemning the principle on which it was based as unsound and untenable.

After such preliminary experiments as he deemed requisite to enable him to ascertain the best form of the REGENERATOR, the inventor at once constructed in LONDON a working engine of five horse power, the performance of which was witnessed by a great number of gentlemen of scientific pretensions in that metropolis. Among others, the popular author, Sir RICHARD PHILLIPS, examined it; and, in his Dictionary of the Arts of Life and of Civilization, he thus notices the result of this experiment. He says:

The author has, with inexpressible delight, seen the first model machine of five horse power at work. With a handful of fuel, applied to the very sensible medium of atmospheric air, and a most ingenious disposition of its differential
powers, he beheld a resulting action in narrow compass, capable of extension to as great forces as ever can be wielded or used by man.

Caloric Engine or Perpetual Motion?

The interest which this subject excited did not escape the British Government. But a short time was permitted to elapse before the Secretary of the Home Department, Lord ALTHORP, now Earl SPENCER, made his appearance in the engine room where the new motive power was in operation. His Lordship was accompanied by Mr. BRUNEL, the constructor of the Thames Tunnel, and a gentleman at one period distinguished for his skill and enterprize as an engineer. At this time he was somewhat advanced in years, and therefore, perhaps, not most judiciously selected by his Lordship to judge of this invention.

At the very outset he conceived an altogether erroneous notion of the nature of the new power, which he would not suffer to be corrected by explanations. An earnest discussion arose between Mr. BRUNEL and the inventor on the spot, which was followed by a protracted correspondence. The result was that an unfavorable impression of the new power was communicated to the British Government.

The invention fared but little better at the hands of Professor FARAYDAY, from whose efficient advocacy and influence the most favorable results might have been anticipated. This gentleman had announced that he would deliver a Lecture on the subject in LONDON, in the spacious theatre of the Royal Institution.

The novelty and interest of the invention, combined with the distinguished reputation of the lecturer, had attracted a very large audience, including many individuals of eminent scientific attainments. Just half an hour, however, before he was expected to enlighten this distinguished assembly, the celebrated lecturer discovered that he had mistaken the expansive principle which is the very life of the machine. Although he had spent many hours in studying the CALORIC ENGINE in actual operation, and in testing its absolute force by repeated experiments, Professor FARAYDAY was compelled to inform his hearers, at the very outset, that he did not know why the engine worked at all.

He was obliged to confine himself, therefore, to the explanation of the Regenerator, and the process by which the heat is continually returned to the cylinder, and reemployed in the production of force. To this part of the invention he rendered ample justice, and explained it in that felicitous style to which he is indebted for the reputation he deservedly enjoys, as the most agreeable and successful lecturer in ENGLAND.

Other causes than the misconception of a BRUNEL and a FARAYDAY operated to retard the practical success of this beautiful invention. The high temperature, which it was necessary to keep up in the circulating medium of the engine, and the consequent oxidation, soon destroyed the pistons, valves, and other working parts. These difficulties the inventor endeavored to remedy, in an engine which he subsequently constructed of much larger powers, but without success. His failure in this respect, however, has not deterred him from prosecuting his invention.

During his residence in this country, Captain ERICSSON has constructed two engines, though purely experimental, with the view of working at a reduced temperature ; and he is gradually, but surely, approaching the realization of his great scheme.

The prescribed limits of a Lecture like the present will not permit me to follow the deeply interesting analogies, traced by ERICSSON, between the principle of the CALORIC ENGINE, and that of animate and terrestrial force. Some of his views and calculations on the subject, however, I cannot omit to present to this audience chiefly to meet the objections of those who imagine that they can detect in the CALORIC ENGINE principles that involve the chimera of the Perpetual Motion.

Nature inspired the Caloric Engine

The sophist accounts for the continued reproduction of the forces expended in nature, by what he calls a nice balance. If this expression fail to convey a distinct idea to those who hear it, it is probably because no very distinct idea on the subject exists in the mind of him who employs it.

He imagines that all force exerted in nature is productive of an equivalent counter-force ; but how nature makes this counter-force subservient he cannot explain. Were his doctrine true, the principle of the CALORIC ENGINE would very much resemble that of the Perpetual Motion ; for its object is the production of a continued force, almost without reference to the amount of the original exciting cause.

Surprising as this may appear, the truth of it is manifested by the principal operating forces in nature, nearly the whole of which, as ERICSSON contends, in a strictly mechanical view, are wasted ; or, in other words, are exerted without producing any useful or available counter-effect. And yet Nature has ever at her command an unlimited amount of force !

To illustrate the amount of this force, I will present one or two calculations by ERICSSON that may excite the astonishment of all who have not had their attention particularly directed to this subject. The quantity of water discharged at the Falls of Niagara is estimated at 28,000 tons a second ; which is equal to 3,360,000,000 of pounds falling through a space of 150 feet in a minute, or of 504,000,000,000 through the space of one foot. If we divide this amount by 33,000, which is the number of pounds that a single horse is capable of moving through the space of one foot in a minute, the result shows the power of the Falls of Niagara to be equal to 15,000,000 of horse power constantly exerted.

Now, an ordinary steam-engine of one horse power, kept constantly at work for one year, consumes twenty tons of coal. To produce by means of steam power, therefore, a constant force, equal to that of the Falls of Niagara, would require the annual consumption of three hundred millions of tons of coal. But the Niagara forms only a small portion of the descent of the St. Lawrence ; and the whole earth is watered by rivers and falls, the united force of which amounts to many hundred times that shown by our calculation. What a stupendous force is here exhibited ! And yet no one can deny that it is in a mechanical sense entirely lost, and that nature reproduces it constantly by FRESH MEANS.

It requires but a word of comment on this illustration, to exhibit the imperfection of the means employed by man for the production of mechanical power. By keeping up a force equivalent to a few millions of horse power in our steam-engines, we are fast exhausting our mineral store-houses ; while Nature, in constantly exerting a force a million of times greater, causes no change any where that is perceptible to the most rigid scrutiny.
Here, then, we have a CALORIC ENGINE on a vast scale, and a REGENERATOR that is susceptible of no improvement.

The forces to which I have hitherto alluded, many will ascribe to solar influence ; a term by which they merely assign a remote location to the acting cause, but fail to explain it. To meet this class of reasoners, ERICSSON has prepared another calculation, based upon those forces in animate nature, for the production of which solar influence is not absolutely necessary. This calculation estimates the amount of force constantly exerted by animate nature, as equivalent to that of an engine of 100,000,000 of horse power.

It is well ascertained that man is capable of exerting a force equal to raising 50 pounds through a space of one hundred feet, for every minute during eight hours out of the twenty-four. This force may not be always exerted, but it is within the ability of every man. Hence we shall underrate the average individual power, if we state it to be adequate to raising ten pounds constantly through a space of one hundred feet per minute ; and, assuming the number of human beings to be 1,000,000,000, their united force will be equal to an engine of 30,000,000 of horse power.

We shall not much err in estimating the force which the quadrupeds are capable of exerting at the same amount ; and the inhabitants of the sea are constantly exerting a far greater force. We know that the power of the whale, for instance, frequently exceeds twenty horse, so that the amount assumed would be made up by a million and a half of these creatures alone. It is obvious, then, that the united force of animate beings on our globe is much more than equivalent to an engine of 100,000,000 horse power.

It has already been stated that an engine of one horse power consumes 20 tons of coal a year. Hence it follows that with OUR present imperfect means of producing mechanical power, we should require TWO THOUSAND MILLIONS of tons annually to exert a force equal to that of animate nature. To maintain that force, therefore, even on our underrated estimate, for a single century, a mere speck in time, would require two hundred thousand millions of tons ; demanding the complete exhaustion of a coal field of 3,000 square miles in extent, with a solid stratum of mineral one hundred feet in thickness. And yet animate nature perpetually maintains this force without any perceptible permanent change.

True it is, we do not know on what mechanical principles it is maintained, nor can we explain the precise cause of animate force ; but it would be irrational to attribute it to the arbitrary will of Omnipotence. We cannot but assume that it depends solely on the mechanical laws of nature ; and in this view of it we are led, irresistibly, to the conclusion that there exists in Nature a principle of absolute reproduction of mechanical force. We need not assert that this principle depends on the extraordinary properties of heat which we have been considering.

It is enough for our purposes to have demonstrated that Nature exerts an infinite amount of mechanical power without causing any perceptible change.

However imperfect may be the principle of ERICSSON'S CALORIC ENGINE, yet it resembles the sublime reproducing principle of Nature, and if not defeated by practical obstacles, this invention will prove a greater boon than the ingenuity of individual man has ever before enabled him to bestow upon his race.