Müller I. A history of thermodynamics. The doctrine of energy and entropy (1185104), страница 6
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Anyway that paper established Mayer’s priority whenJustus von Liebig (1803–1873) published it in his “Annalen der Chemieund Pharmacie”. To be sure, Mayer did not give Liebig much of a choice;his accompanying letter would have flattered any hard-nosed editor intoacceptance, cf. Fig. 2.3. Those readers who have a command of Germanmay learn from the letter how editors should be approached.There is a peculiar type of reasoning in the paper. Mayer, rather than justpostulate the conversion of motion to heat and make it plausible, attempts toprove his discovery from some perceived theorem of logical cause or froman assumed axiom causa aequat effectum. On another occasion, theconservation of energy – force for Mayer – is summarized in the sloganEx nihilo nil fit.
Nil fit ad nihilum.Robert Julius Mayer (1814–1878)17Fig. 2.2. Robert Julius Mayer. Cut from the title page of his first published paperFig. 2.3. Cut from Mayer’s letter accompanying the paper submitted to LiebigWe have to make allowance, however, for Mayer’s almost completeisolation.
Occasionally he sought scientific advice from physics professors,but then he was fobbed off with the demand to support his theory byexperiments and, in one case, he was sent home with the information thatthe area of science was already so big that an extension was undesirable.21So he was thrown back to his family and a few friends for scientificmonologues. They understood nothing and naturally they thought that theirhusband and friend was more than a little crazy. The pressure on Mayermounted when his priority claim was ignored by Joule, and Helmholtz, andby a lesser man – a Dr. Otto Seyffer – who ridiculed Mayer’s ideas in anarticle in the daily press.22 Two of his children died and Mayer came close21Reported by Mayer in a letter to his friend W.
Griesinger on June 14th 1844. Mayer’scorrespondence with some of his friends is included in the collection of his works.Reprinta historica didactica. loc cit. Bd. 1, p. 121.22 “Augsburger Allgemeine Zeitung” from May 21st, 1849.182 Energyto being executed as a spy by some republican radicals who – in the courseof the revolution of 1848/49 – briefly won the upper hand in parts ofWürttemberg. In 1850 all this led to an attempted suicide when Mayerjumped from the third floor of his house into the yard 9 meters below.
Hesurvived but was permanently slightly crippled.Mayer’s relatives sought the professional help of an alienist who was afriend of the family. However, the man was also young, and new in hispractice, and he needed the money. Therefore he had no intention to letMayer go anytime soon.
He put him behind bars and for good measure kepthim in a straightjacket. Eventually, after 13 months of this, Mayersucceeded to escape and he reached home by foot in his nightgown. Afterthat he was indeed a trifle neurotic, patients stayed away from him and thestreet urchins would taunt him: There he goes, the dotty Mayer.However, my former critical remarks on Mayer’s papers must not givethe impression that Mayer was anything less than a very original scientist.And despite the evidence of the papers mentioned above, he could writewell, if he did not force himself to be excessively brief, – and if he did notattempt to use mathematics.
The style of his brochure “Die organischeBewegung in ihrem Zusammenhang mit dem Stoffwechsel”23, published in1845 by a small Heilbronn printing shop, is still idiosyncratic, but it is clear.Among the subjects which Mayer takes up in that extensive memoir, Imention a few in order to show the scope of his purpose:x Mayer overcomes Carnot and Clapeyron and paves the way forClausius when he speaks of the heat engine and says … the heatabsorbed by the vapour is always bigger than the heat released duringcondensation. Their difference is the useful work.x He explains in detail how he calculated the mechanical equivalent ofheat, cf. Insert 2.1. That argument was too brief in his 1842 paper to beunderstood and appreciated.
The calculation is a solid piece ofthermodynamics – now very elementary – and it had nothing to do withhorses stirring paper pulp in cauldrons, as folklore has it. To be sure,those horses are mentioned in the article, and some roughmeasurements of the temperature of the pulp, but these were far fromgood enough to calculate the mechanical equivalent of heat.Incidentally, in this context Mayer mentions Rumford; therefore heknew about Rumford’s experience with boring cannon.x He also reports that a cannon barrel which shoots a ball becomes lesshot than if the powder alone is ignited in the barrel.
Mayer says that thefact is common knowledge. Well, maybe it was at the time. Anyway, theobservation makes sense: Part of the chemical energy of the powder is23[Organic motion and metabolism] Verlag der C. Drechslerschen Buchhandlung, Heilbronn(1845).Robert Julius Mayer (1814–1878)19converted into the kinetic energy of the ball, if there is a ball. Otherwiseall goes into heat.x Mayer extrapolates that observation to the metabolism in animals, andmen.
The heat liberated by the chemical process of digestion, or ofinternal combustion of food, can partly be converted into work, he says,whereupon the body becomes colder. In order to support this idea hecites an observation that was published in the “Journal de Chimiemédicale, VIII Année, Février”, where the author – a man by the nameof Douville – measured the temperature ofa negro lazy and inactive in the cabin 37°dittodittoin the sun 40.20°dittoactivein the sun 39.75°.x Pursuing the idea further, Mayer says that a man sawing wood freezesin the arm which moves the saw.
Also a blacksmith who heats a pieceof iron to red-heat with three strokes will be cold in the arm that wieldsthe hammer. He says that he has observed that the busy parts of thebody sweat less during continual hard work than the inactive ones. Forthis latter observation he cites biblical proof. Namely when God says toAdam: In the sweat of your brow you shall eat bread. Mayer seems tothinks that Adam will henceforth work with his hands and feet, whichwill therefore sweat less than the head which is involved but little, ornot at all.x In the same memoir Mayer comes out strongly against the vis viva,the hypothetical force postulated by physiologists of the time – evenLiebig – to explain organic processes, or rather to set them aside asunexplainable.x The heat of the earth – put in evidence by warm springs andvolcanoes – is explained by Mayer as the equivalent of the kineticenergy with which the constituent masses crashed together at the timewhen the earth was formed.
In a rough-and-ready calculation heestimates the original temperature to have been 27600°C, enough forthe earth to have been liquid, or actually gaseous.We could continue the list of Mayer’s thoughts on mechanics,astronomy, biology, and physiology by dozens of more item. Maybe theyare not all correct, but they are all original. Like the theory of the heat of theearth, or when he thinks that the solar energy stems from the meteorswhich fall into the sun. Sometimes he capitulates, like when he wonderswhy planets have orbits with rather small ex-centricities. He suspects thatthis might be explainable by his ideas on the conversion of motion into heatbut cannot do it.
Calculations of tidal forces were far beyond hismathematical ability.Most of the brochure of 1845 is written in a matter-of-fact style, but atthe very end Mayer’s propensity for hyperbole breaks through again. Thus202 Energythe work ends with the sentence: …may the phenomena of life be comparedto a wonderful music full of melodious sounds and touching dissonances;only in the concert of all instruments lies harmony and only in harmony lieslife.For all that, however, Mayer never knew what the nature of heat was.
Inhis brochure “Bemerkungen über das mechanische Äquivalent derWärme”24 in 1851 he says that ... the connection between heat and motion isone of quantity rather than quality and he tends to assume that … motionmust stop in order to become heat. Here he was wrong and he could haveknown it. Indeed, the fledgling mechanical theory of heat existed alreadyand in a short time – in the hands of Maxwell – it should rise to its firstpeak.
By that theory, the kinetic energy of motion of a body was just redistributed among its atoms when it seemed to disappear; and heat was howthat re-distributed motion was felt. Helmholtz, about whom Mayercomplains for not having given his work proper credit, explains the relationbetween heat and atomic motion very well.Mayer in some way was burned out by that time, he missed the furtherdevelopment of what he had helped to start, although he lived until 1878,one year before Maxwell died. Ironically he did receive some recognitionafter he had stopped working seriously.
John Tyndall (1820–1893), a wellregarded physicist and prolific science author,25 supported Mayer in hispriority quarrel with Joule, and Mayer received the Copley medal from theRoyal Society of London. In 1858 Liebig called Mayer the father of thegreatest discovery of the century and in 1859 Mayer received an honorarydoctorate from his old alma mater in Tübingen.The chamber of commerce of Heilbronn elected Mayer to honorarymembership, and the king of Württemberg …whose pleasure it is to rewardgreat achievements26 made Mayer a knight of the order of the Württembergcrown. Mayer could now call himself “von Mayer”.Yet, Mayer is largely forgotten, but not in his hometown Heilbronn.
Thepeople in the town archive look after his memory with loving care.27 Hisbronze statue is displayed in a prominent spot of the town, and themonument carries the somewhat pompous quatrain24[Remarks on the mechanical equivalent of heat] Verlag von Johann Ulrich Landherr,Heilbronn (1851) Bd. 1, p. 169.25 Tyndall is best known for his work on light scattering. It was he who explained the bluecolour of the sky, but he also wrote a book on thermodynamics entitled “Heat as a mode ofmotion” which appeared in 1863.26 So Mayer in an autobiographical note.
Reprinta historica didactica. loc.cit. Bd. 1, p. 8.27 When I visited the archive, I had to park my car precariously. A policeman promptlyshowed up, but, as soon as he heard that I was interested in Mayer he promised to watchover my car: “Take as long as you like, sir.”James Prescott Joule (1818–1889)21Wo Bewegung entsteht, Wärme vergehtWo Bewegung verschwindet, Wärme sich findetEs bleiben erhalten des Weltalls GewaltenDie Form nur verweht, das Wesen besteht.James Prescott Joule (1818–1889)Joule was the son of a rich brewer who was tolerant enough of the scientificinterests of his son to furnish him with a home-laboratory.
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