ll. t. Ch . 13 14 ( 2 2 tr n nd p t A r n lt n f t r , v d lf r, th tr d t n l pr n pl f l t n r l d f d n n f t n p r pl n r n d f x v l t t n , t n, r pr nt n " tt r." S " x t Al h ", r f r n pr nd f r t rr pt n ." , pp. 6 6 , 8 86. 25. Ibid., p. 68 : "... pr pr & x t l nd n p r 4 . W. n, " t n Clavis St r Key," Isis,1987, t ll t n ..." 78, 64 4. 26. W. n, The "Summa perfectionis" of pseudo-Geber, 46. h l l th , Introitus apertus, BCC, II, 66 , "... lph r xt r d n, , pp. 4 2. n ..." 2 . l , " t n Al h t," r f r n , pp. 2 24. 4 . f r n 4 , pp. 2 4. 28. [E r n h l l th ,] Sir George Ripley's Epistle to King 48. bb , Foundations , r f r n , p. 2 8. Edward Unfolded, MS. Gl Un v r t , r n 8 , pp. 80, 4 . l , " x t Al h ", r f r n , p. 64. p. . 0. bb , Foundations, r f r n , pp. 222 22 . 2 . MS. r n 8 , p. . Cf. l Philalethes,Introitusapertus, . W tf ll, Never at Rest, r f r n 8, p. 8. in Bibliotheca chemica curiosa, n M n t, r f r n 2, l. II, p. 2. r t ll b f l t v b th t n p r phr 664. (C br d Un v r t br r , K n MS. 0, f. 22r nd th 30. Ibid., MS. r n 8 , pp. 2. r n l ( h l l th , Introitus apertus, in Bibliotheca chemica curi- 31. Ibid. osa, l. II, p. 66 : 32. Ibid., pp. 6. Newton: h t t rr pr pt r l t n , t 33. Ibid. n r l tr x pr pt r n r l n p lt nt r, t 4. l , " t n Al h t," r f r n , p. 20. t n r v l t l , t l [ lph r ] n tr r v lv nt r . [E r n h l l th ,] Sir George Riplye' s Epistle to King nt n t n ntr , d ntr t t t & t rr n d Edward Unfolded, n Chymical, Medicinal, and Chyrurgical AD- p rf ll n t. Intr t. p rt p. 0. DRESSES: Made to Samuel Hartlib, Esquire ( nd n, 6 , p. 22. Philalethes: Ch t n tr t M n r l rr , 6. h rd "n l " th t n t r f r " rn l" r "n t." l t n r p t , & t n r v l t l , ntr d t h l l th t n h nf n h d n r pt f th Vade mecum C l h l ph r n C ntr , d C ntr t r v r Philosophicum ( r t h br r , MS. Sl n 6 , 0 v . A tr l , rr d n rr d p rf j b r . . h xpl n t n f rr d b l t pr d t f p r t n th b t l npl n th l h l tr d t n t l z d b h l l th . Cf. n, r f r n 26, p. 8, n t n th William R. Newman teaches in the History of Science Depart- Summa: r pt r n r [ . . pp r nd r n] lt t rr t t ment at Harvard University, Science Center 235, Cambridge, nt t t t lph r t t dj t v t f nt n r , d f l MA 02138. His publications include the monograph "The h d dd nt r n l . Et M d d , n x lt 'Summa perfectionis' of pseudo-Geber" and the forthcoming t rr t t r nt v v b t nt nt r xt t rb t r r nt v v nt n volume "Gehennical Fire: The Lives of George Starkey, an t , t d p r t n r t r, p r t lph r t tr n n Alchemist of Harvard in the Scientific Revolution." v l r p t t. Et n x ll d rn d n b r r t l v r p t t ll . r h t r d r l n t r tp rt r r r f r t n n r p r d nt n t t r r t t nv rt ." 8. I. t n, Opticks, v r, Y r , Y, 2, p. 400. ROBERT MAYER AND THE . A. h r , Atoms and Powers, rv rd Un v r t r , CONSERVATION OF MATTER C br d , MA, 0, pp. 2 nd 64. 40. r t n d t n t n b t n "v l r Ch tr " nd Kenneth L. Caneva, University of North Carolina at " r t " ph l ph , . M. tt n , " t n Al h l Greensboro St d ," n A. G. b , d., Science, Medicine, and Society in the Renaissance, l W t n bl t n , Y r , Y, 2, pp. Robert Mayer (1814-1878) is well known as one of the discov- 6 , nd 0. erers of the principle of the conservation of energy. A physi- 4 . f r n 8, p. 86. cian from the kingdom of Württemberg in southwestern Ger- 42. I. . C h n, Isaac Newton's Papers & Letters on Natural many, Mayer sailed to the Dutch East Indies in 1840, where he Philosophy, rv rd Un v r t r , C br d , MA, 8, p.2 2. was startled by the brighter-than-expected color of the blood he Al bb , Foundations, r f r n , p. 2 . let from European sailors recently arrived in the tropics. 4 . bb , Foundations, r f r n , p. 220. Reflecting on the implications of Lavoisier's combustion 44. l r , f rth r r , th t t n t d th l h theory of animal heat, and of his own failed childhood attempt t r r th th pr n f "p r " ( nd h n v d n to construct a perpetual motion machine, Mayer employed a tt r, h n th r l n v th t r r th pr n pl widely invoked analogy between organisms and machines to f v l t l t nd h n tt n t n. S l rl h th n th t t n conclude that there must be a constant numerical relationship 28 Bull. Hist. Chem. 4 (1992-93) between heat and "motion" (1). Two years later he published his first paper, "Remarks on the Forces of Inorganic Nature", in Liebig's Annalen der Chemie und Pharmacie. That paper contained his calculation of the mechanical equivalent of heat; as he put it, the fall of a given weight through a distance of 365 meters is equivalent to a rise in temperature of one degree Celsius of an equal weight of water. Although this essay cannot develop the full context of Mayer's reflections, it is important to recognize that the line of reasoning sketched above yielded Mayer a number, not a general concept of energy (he said "Kraft", or force), let alone of its conservation. Of central importance in the exposition of his theory of force was an analogy between force and matter - the fundamental concepts, he argued, of (respectively) physics and chemistry. Both force and matter are quantitatively invariable and qualitatively variable. Just as matter is, in the normal course of nature, neither creatable nor destructible, so, too, is force neither creatable nor destructible, at least as far as the processes of inorganic nature are concerned. It is thus tempting to suspect that Mayer transferred to the new concep- tual entity "force" the well-known chemical principle of the conservation of matter. The only thing wrong with this explanation is that there was no such principle in the chemistry and physics texts of the first half of the 19th century, at least not in Germany. The substance of the principle was, to be sure, tacitly assumed as a working principle by chemists, but it had no visibility as a fundamental principle, let alone the fundamental principle upon which the b rt M r science of chemistry is based. In a real sense Mayer had to "discover" for himself the principle we know of as the conser- over terms. I've looked at about 30 works by 17 authors from vation of matter. Nor was it a simple business for him to settle the 1820s till the early 1840s, including the well-known texts upon the analogy between force and matter. He first had to of Baumgartner, Berzelius, Biot, Leopold Gmelin, Kastner, define for himself the meaning of force and to decide what its Mitscherlich, Pouillet, and Wailer. Most list as the general fundamental characteristics were. It was only gradually and properties of matter things like extension, impenetrability, with great conceptual difficulty that Mayer concluded that divisibility, porosity, elasticity, compressibility, inertia, and force, too, cannot be created or destroyed under any circum- motility, rarely also weight or gravity ("Schwere"). Some stances. He never doubted the indestructibility and uncreata- don't even mention mass as an important concept, let alone its bility of matter, but whether those characteristics apply also to conservation. force was precisely the difficult question to answer. A con- One of the standard reference works of the day was Gehler' s fused application of the parallelogram of forces to central- Physical Dictionary, published in 11 multipart volumes be- force motion, coupled with residual uncertainty as to the status tween 1825 and 1845. Neither the short article on "Mass" nor of the vital force and attachment to a widely invoked image of the long one on "Matter" specifically mentioned its conserva- the solar system as an "organism," led him to conclude until tion or indestructibility (2). To be sure, passing mention of around 1844 that force is continuously produced in the sun via such a principle did occur here and there in the course of the neutralization of a portion of the planets' centrifugal force. particular discussions, quite as Lavoisier's oft-quoted enun- In other words "organisms," unlike machines, are truly capable ciation of it was tucked away in the section of his Traite dealing of creating force effectively out of nothing. with vinous fermentation. Thus Lam6 referred to "the inde- The nonexistence of an explicit principle of the conserva- structibility of matter and the constancy of the quantity of vis tion of matter is as unambiguous as it is startling. The viva" in his discussion of the constancy of the quantity of heat overwhelming majority of German chemistry and physics in certain reactions, but he otherwise passed in complete texts and handbooks of the period contain no explicit mention silence over the conservation of matter (3). Interestingly of anything like the conservation, indestructibility, or un- enough, the two other incidental references I've encountered to creatability of matter, mass, or substance. One needn't quibble something like the conservation of matter have to do with
Bull. Hist. Chem. 13 14 (1992-93) 29 reactions involving oxygen - perhaps a faint resonance of the voisier?) of the fact that the weight of the chemical reagents historical association of that principle with Lavoisier. before and after a reaction must be unchanged, but rather the Such silence is perhaps doubly surprising since not only had explicit enunciation of a particular principle and the kinds of Lavoisier enunciated the principle of the conservation of assumptions which finally made that enunciation reasonable in matter in 1789, but in Germany Immanuel Kant had laid down ways it hadn't been before. The parallel and explicit formula- a similar principle in his influential Metaphysical Foundations tion of both conservation principles as fundamental principles f Natural Science of 1786. For Kant, the first principle of of the sciences of chemistry and physics was in the first mechanics was that "in all changes in the corporeal world the instance the work of Robert Mayer. Lavoisier notwithstand- quantity of matter remains on the whole the same, unincreased ing, it appears to me that, for the larger scientific community, and undiminished." Yet Kant also assigned to matter primitive the general recognition of the principle of the conservation of attractive and repulsive forces, and the "dynamical" philoso- matter went hand in hand with, and was only made possible by phies of nature which were popular in early 19th-century the general acceptance of the principle of the conservation of Germany tended to eliminate matter entirely in favor of its energy during the second half of the 19th century. construction out of ontologically more primitive forces; hence there was no matter, let alone mass, to be conserved. f r n nd t The very notion of the conservation of matter was problem- atic because of the widespread lack of precision concerning the . t l b t M r r n b f nd n b , Robert conception of matter as a distinct entity, especially as it related Mayer and the Conservation of Energy, r n t n Un v r t r , to the nature of the so-called imponderables, i.e. heat, light, . h t r l nt n r f ll d nt d r v f th electricity, and magnetism, regarded as weightless fluids. h l l t r t r r f rr d t h r . (Recall here that even Lavoisier listed caloric and light among 2. . W. r nd nd G. W. M n , "M " nd "M t r ," n the elements.) One prominent writer, Jacob Friedrich Fries, . W. r nd t l., Johann Samuel Traugott Gehler' s Physikal- interpreted ponderable matter and the so-called imponderables isches WOrterbuch, 11 l . n 20 pt ., pz , 82 4 , l. 6, pt. as merely different states of aggregation of the same underly- 2, 8 6, pp. 2 nd 4 2, r p t v l . ing substance (4). This was a notion which held out the implicit 3. G. , Cours de physique de l'Ecole polytechnique, pt . possibility of the effective disappearance of ponderable matter n 2 l ., r , 8 6 , l. , 8 6, p. 428. and hence cut the ground from under the utility of a principle 4. . . r , Lehrbuch der Naturlehre, n , 826, p. . of the conservation of matter. Heidelberg professor of physics . G. W. M n , "I p nd r b l n [ ]," n r f r n 2, l. Georg Wilhelm Muncke insisted that the alleged weightless- , pt. 2, 8 0, pp. 6 6 . ness of the imponderables had not been proven empirically, 6. . . . A t nr th, Handbuch der empirischen menschlichen and thus he held open the possibility that they were only Physiologie, l ., b n n, 80 802, l. 2, 802, pp. 8 tenuous states of matter, again blurring the concept of ponder- 0. able matter and rendering its conservation less than obvious (5). As he observed, the imponderables would only have to be as light with respect to hydrogen as hydrogen is with respect to Kenneth Caneva is an Associate Professor in the Department platinum in order to escape detection by our most sensitive of History ,University ofNorth Carolina at Greensboro ,Greens- balances. One of Mayer's professors of medicine at Tubingen, boro,NC 27412. He specializes in early 19th-century German the then-prominent Johann Heinrich Ferdinand Autenrieth, science, and has recently published a book on Robert Mayer concluded his discussion of phenomena of electricity, galva- and the conservation of energy. nism, magnetism, chemical reactions, heat, and light with the judgment that "imponderable substances" differ only in degree from "ordinary heavy bodies: They do not constitute a class of PRIDE AND PREJUDICE IN CHEMISTRY entities wholly different from the other material substances, and between the magnetic fluid and rigid flint there is an almost Chauvinism and the Pursuit of Science continuous transition" (6). In other words, it would be hard to insist on the conservation of matter as a principle if one's Alan J. Rocke, Case Western Reserve University conception of ponderable matter was such that there was nothing in principle to conserve. It took the clarification of the Imbued as they are with the ideal of scientific objectivity, concept of energy and the abandonment of the time-honored scientists and their historians can forget or neglect an important but vague notion of the imponderables before the concept of truism: scientists are just as susceptible as their fellow human matter was distinct enough to make its n rv t n n beings to chauvinism, bigotry, greed, ambition, and all the n f l principle of science. other faults t h h h n t pr . news articles At issue is not chemists' routine acceptance (after La- published in Science in 1989 are relevant relevant to the first sin in my