A Geologist among Astronomers: The Rise and Fall of the Chamberlin-Moulton Cosmogony,Part 1

Chamberlin T. C. to Frost E. B. , 26 December 1905; copy in Box 1, folder 16, Chamberlin Thomas C. Papers, The Department of Special Collections, The University of Chicago Joseph Regenstein Library (hereafter cited as C-UC).

Chamberlin T. C. Salisbury R. D. , Geology , ii (New York, 1906), ch. 1.

For surveys of theories of planetary cosmogony see: ter Haar D. Cameron A. G. W. , “Historical Review of Theories of the Origin of the Solar System”, in Jastrow R. Cameron A. G. W. , eds, Origin of the solar system (New York, 1963), 1–37; Herczog T. , “Planetary Cosmogonies”, Vistas in astronomy , x (1968), 175–206; Williams I. P. , The origin of the planets (London, 1975); Jaki S. L. , The puzzling world of planets (forthcoming); Hartmann W. K. , Moons and planets (Belmont, Calif., 1972), ch. 4.

Burchfield J. D. , Lord Kelvin and the age of the Earth (New York, 1975). Brush S. G. , The temperature of history (New York, 1977), ch. 3.

[ Chambers R. ], Vestiges of the natural history of creation (London, 1844). Spencer Herbert , First principles (London, 1862); “Recent Astronomy and the Nebular Hypothesis”, Westminster review , n.s., xiv (1858), 185–225. Ogilvie M. B. , “Robert Chambers and the Nebular Hypothesis”, British journal for the history of science , viii (1975), 214–32.

Numbers R. L. , Creation by natural law: Laplace's nebular hypothesis in American thought (Seattle, 1977).

Stocking G. W. Jr , Race, culture, and evolution: Essays in the history of anthropology (New York, 1968), 69–132. Harris Marvin , The rise of anthropological theory (New York, 1968), 108–216.

Stocking , op. cit. (ref. 7), 133–269. Harris , op. cit. (ref. 7). Cravens H. , “The Abandonment of Evolutionary Social Theory in America: The Impact of Academic Professionalization upon American Sociological Theory, 1890–1920”, American studies , xii (1971), 5–20. Cravens Hamilton Burnham John C. , “Psychology and Evolutionary Naturalism in American Thought, 1890–1940”, American quarterly , xxiii (1971), 635–57. Rádl E. , The history of biological theories (London, 1930), ch. xxxiii.

Brush S. G. , “Scientific Revolutionaries of 1905: Einstein, Rutherford, Chamberlin, Wilson, Stevens, Binet, Freud” (to be published).

MacPherson H. C. , A century's progress in astronomy (Edinburgh, 1906), 233.

Newcomb S. , Astronomy for everybody (London, 1903), 106.

Ball R. , The Earth's beginning (London, 1901). Becker G. F. , “Kant as a Natural Philosopher”, American journal of science , (4) v (1898), 97–112. Berget A. , Physique du globe et météorologie (Paris, 1904), 45–51. Berry A. , A short history of astronomy (New York, 1961, rept. of 1898 ed.), 409. Cortie A. L. , “The Origin of the Solar System”, American Catholic quarterly review , xxiv (1899), 19–27. Darwin G. H. , The tides and kindred phenomena in the solar system (Boston, 1898), 338. de Launay L. , La science geologique (Paris, 1905), 705. Fison A. H. , Recent advances in astronomy (London, 1898), ch. 1. Geikie A. , Class-book of geology (London, 1894), 227–8; ibid. , 4th ed. (London, 1894), 252–3. Howe H. A. , A study of the sky (Meadville, Pa., 1896), 327–33. Klein H. J. , “Neue Untersuchungen über die frühesten Zustände der Erde und des Mondes”, Sirius , xxxvi (1903), 1–5. Mascart J. , “Contribution à l'Origine des Petites Planètes”, Bulletin, Société Astronomique de France , xvi (1902), 123–6. Mooser J. , Theorie der Entstehung des Sonnensystems, Eine mathematische Behandlung der Kant-Laplace'schen Nebularhypothese , neue Bearbeitung (St Gallen, 1904). Morehouse G. , The wilderness of worlds (New York, 1898), 39, 56. Moulton F. R. , “Some Points which Need to be Emphasized in Teaching General Astronomy”, Popular astronomy , iv (1896), 242–7. Ritter G. A. , Das Weltall und die Entwicklungsgeschichte der Erde (Berlin, 1906), 64–78; Die Wunder der Weltall (Berlin, 1909), 64–78. See T. J. J. , Researches on the evolution of the stellar systems , i (Lynn, Massachusetts, 1896), 1–3; Seemann Friedrich , “Zur Kant-Laplaceschen Theorie”, Prometheus , xi (1900), 753–6. Shaler N. S. , Outlines of the Earth's history (New York, 1898), 34–8. Sollas W. J. , Presidential Address to Geology Section, Nature , lxii (1900), 481–9. Todd David P. , Stars and telescopes (Boston, 1899), 45–248. Von Braümuller , “Geschichtliche Darstellung der hauptsächlichsten Theorien über die Entstehung des Sonnensystem”, Himmel und Erde , x (1898), 289–300, 357–74. Young Charles A. , A textbook of general astronomy, (rev. ed., Boston, 1900), 566–74.

There were some indications of the peculiar nature of the Uranus system even before Laplace published his theory, but there was disagreement about how many satellites there were, and the motions were not reliably established until William Lassell's observations in 1851. For details see Alexander A. F. O'D. , The planet Uranus (London, 1965).

“… if the different satellites of a planet move in the same plane, which is considerably inclined to the plane of the orbit of the planet; we may conclude, that they are retained in this plane by the action of its equator; consequently the planet must have a rotatory motion about an axis, which is nearly perpendicular to the plane of the orbits of the satellites. Therefore we may affirm, that the planet Uranus, whose satellites move in a plane nearly perpendicular to the ecliptic, revolves about an axis, which is very slightly inclined to the ecliptic” ( de La Place Marquis , Celestial mechanics , trans. Bowditch Nathaniel , ii (Bronx, New York, 1966; reprint of 1832 ed.), 989).

Faye H. , “Sur l'Origine du Système Solaire”, Comptes Rendus , Académie des Sciences, Paris, xc (1880), 637–43; “La Formation du Système Solaire”, Astronomie , iii (1884), 161–70; Sur l'origine du monde. Theories cosmogoniques des anciens et des modernes (1st ed., Paris, 1884; 2nd ed., 1885; 3rd ed., 1896; 4th ed., 1907).

Darwin G. H. , “The Cosmogonic Theory of M. Faye”, Nature , xxxi (1885), 506–8.

Kirkwood Daniel , “On Certain Harmonies of the Solar System”, American journal of science , (2) xxxviii (1864), 1–18.

Descartes René , Les principes de la philosophie , quatrième edition, reprinted in Oeuvres de Descartes , ed. Adam C. Tannery P. , ix (Paris, 1904), Troisième Partie, 148.

Babinet Jacques , “Note sur un Point de la Cosmogonie de Laplace”, Comptes rendus, Académie des Sciences, Paris , lii (1861), 481–4. Since ‘Babinet's criterion’ has become known as a principal cause of the downfall of the nebular hypothesis in the twentieth century, it should be noted that Babinet was a strong supporter of the hypothesis in the 1850s. See his Études et lectures sur les sciences d'observation et leurs applications pratiques , iv (Paris, 1857), 47–49 (lecture in May 1855), vii (Paris, 1863), 99–114 (lecture in December 1860). See also André C. , “L'hypothèse nébulaire de Laplace et la théorie de la capture de M. T. J. J. See”, Scientia , xi (1912), 153–69; Jeans J. H. , Problems of cosmogony and stellar dynamics (Cambridge, 1919), 272, 275.

Fouché Maurice , “Sur la condensation de la nébuleuse solaire, dans l'hypothèse de Laplace”, Comptes rendus, Académie des Sciences, Paris , xcix (1884), 903–6.

von Helmholtz Hermann , Ueber die Wechselwirkung der Naturkräfte und die darauf bezuglichen neuesten Ermittelungen der Physik (Königsberg, 1854). This was a popular lecture on various applications of the energy principle, widely reprinted and translated. For Helmholtz's views on the nebular hypothesis see also “Ueber die Entstehung des Planetensystems” (1871), in his Vorträge und Reden , ii (5th ed., Braunschweig, 1903), 53–91.

Thomson William , “On the Age of the Sun's Heat”, Macmillan's magazine , v (1862), 388–93. Burchfield , op. cit. (ref. 4), ch. 2.

See ref. 4.

Croll James , “On Geological Time, and the Probable Date of the Glacial and the Upper Miocene Period”, Philosophical magazine , (4) xxxv (1868), 363–84; “On the Probable Origin and Age of the Sun”, Journal of science , (2) vii (1877), 307–26; Stellar evolution and its relations to geological time (London, 1889).

Kelvin , “The Age of the Earth as an Abode Fitted for Life”, Journal of the Victoria Institute, London , 1897, xxxi (1899), 11–35; Philosophical magazine , (5) xlvii (1899), 66–90.

Kirkwood Daniel , “On the Nebular Hypothesis, and the Approximate Commensurability of the Planetary Periods”, Monthly notices of the Royal Astronomical Society , xxix (1869), 96–102; “The Cosmogony of Laplace”, Proceedings of the American Philosophical Society , xviii (1879), 324–6. Another objection along this line was published by Stockwell John N. , “Theory of the Mutual Perturbations of Planets Moving at the same mean Distance from the Sun, and its Bearing on the Constitution of Saturn's Ring and the Cosmogony of Laplace”, Astronomical journal , xxiv (1904), 35–39. Stockwell argued that the material in a ring would collect into two planets 60° apart rather than a single one. See comments by Lynn Crommelin and others in Journal of the British Astronomical Association , xiv (1904), 229–31, 239–41.

Roche Édouard , “Essai sur la Constitution et l'Origine du Système Solaire”, Mémoires de l'Académie des Sciences et Lettres, Section des Sciences , viii (1873), 235–324.

“The Nebular Hypothesis vanishes as a pleasant dream, profitable though we believe it has been; and with it various systems of cosmogony, the fear of timid Christians, and the hope of Atheistical philosophers” ( Taylor George , The indications of the Creator: Or, The natural evidence of final cause (New York, 1851), 54). The results of Rosse “were regarded by the majority of astronomers as fatal to the claims of the nebular hypothesis” according to Daniel Kirkwood, “On the Testimony of the Spectroscope to the Truth of the Nebular Hypothesis”, American journal of science , (3) ii (1871), 155–6.

According to a respected authority, Whewell in 1853 and Spencer in 1858 showed that “the conception of the nebulae as remote galaxies which Lord Rosse's resolution of many into stellar points had appeared to support” was untenable; nebulae and stars are found in the same regions, hence must be part of the same system ( Clerke Agnes M. , A popular history of astronomy during the nineteenth century (4th ed., London, 1902), 422).

Huggins himself did not at first admit the relevance of his discovery to the evolution of the solar system because, he later confessed, he was “under the undue influence of theological opinions”. See his “Celestial spectroscopy”, presented to the British Association, 1891, reprinted in Essays in astronomy by Ball, etc. (New York, 1900), and “The New Astronomy: A Personal Retrospect”, Nineteenth century , xli (1897), 907–29.

Roberts Isaac , “Photographs of the Nebula M31, h 44, and h 51 Andromeda, and M27 Vulpeculae”, Monthly notices of the Royal Astronomical Society , xlix (1888), 65.

Keeler James E. , “The Crossley Reflector of the Lick Observatory”, Astrophysical journal , xi (1900), 325–49. Wilson H. C. , commenting on the appearance of the Andromeda nebula, wrote that “A better confirmation of the Nebular Hypothesis of world formation can hardly be found” but he meant the formation of stars, not planets. See “The Great Nebula in Andromeda”, Popular astronomy , vii (1899), 507–10.

Saubert , “Moultons neue Idee über Planetenentstehung”, Die Natur , xlix (1900), 250; Hnatek Adolf , “Die Entstehung des Planetensystems”, Naturwissenschaftliche Wochenschrift , xv (1900), 553–7; Heysinger I. W. , Solar energy (2nd ed., Philadelphia, 1901), 285–95; Nölke Friedrich , Das Problem der Entwicklung unseres Planetensystems (Berlin, 1908), 138ff.

Brewster David , More worlds than one: The creed of the philosopher and the hope of the Christian (London, New York, 1854), 45–46; Memoirs of the life and discoveries of Sir Isaac Newton (London, Edinburgh, 1855; New York, 1965), ii, 131. Agassiz Louis , introduction to Miller Hugh , The foot-prints of the Creator (Boston, 1851), p. xxv. Peirce Benjamin , “On the Constitution of Saturn's Ring”, American journal of science , (2) xii (1851), 106–8 (see last paragraph).

Kirkwood Daniel , “On the Nebular Hypothesis”, American journal of science , (2) xxx (1860), 161–81; Whewell William , Astronomy and general physics considered with reference to natural theology , Book ii (London, 1833), ch. 7. One clergyman attacked the nebular hypothesis but also tried to show that even if it were accepted it would still illustrate the agency of divine power, through “mediate” rather than “immediate” creation. Buchanan James , Modern atheism (Boston, 1857), 56–60. See also Numbers, op. cit. (ref. 6).

Hutt Alexander Chambers G. F. , discussion remarks, Journal of the British Astronomical Association , xiv (1904), 150–5. For a theological defence of the nebular hypothesis see Leahy George V. , Astronomical essays (Boston, 1910), 234, 253, 259.

Wallace Russel Alfred , “Man's Place in the Universe: As Indicated by the New Astronomy”, Fortnightly review , (n.s.) lxxiii (1903), 395–411; Man's place in the universe (New York, 1903).

Brayley E. W. , “Physical Constitution and Functions of the Sun, and Sources of its Heat and Energies, as Recently Investigated”, Companion to the British almanac for 1866, 75–113 (see p. 95); Proctor Richard A. , Other worlds than ours (London, 1870), 201–9; Prestwich Joseph , “On the Past and Future Work of Geology”, Nature , xi (1875), 290–2 (report of Lockyer's theory). Wallace A. R. ( My life (London, 1905), i, 427) mentioned an anonymous article, “The Birth of the Solar System. A New Theory”, Atlantic monthly , xxiii (1869), 221–8.

Darwin G. H. , “On the Mechanical Condition of a Swarm of Meteorites, and on Theories of Cosmogony”, Proceedings of the Royal Society of London , xlv (1888), 3–16; Philosophical transactions , clxxx, 1–69.

Bickerton A. W. , “Partial Impact (Paper No. 2): A Possible Explanation of the Origin of the Solar System, Comets and Other Phenomena of the Universe”, Transactions of the New Zealand Institute , xi (1878), 125–32; “On the Genesis of Worlds and Systems”, ibid. , xii (1880), 187–97; “On the Causes Tending to Alter the Eccentricity of Planetary Orbits”, ibid. , xiii (1880), 149–54; “The Origin of the Solar System”, ibid. , xiii (1880), 154–9; “Synoptic Statement of the Principles and Phenomena of Cosmic Impact: Prepared for the Criticism of Scientific Men and Societies”, ibid. , xxvii (1895), 545–58; The romance of the heavens (London, 1901). Extracts from two of the 1880 papers are included in A source book in geology , ed. Mather Kirtley F. Shirley L. Mason (New York, 1964), 574–7.

In 1910 Bickerton succeeded in raising funds for a trip to England, where he obtained a respectful hearing for his views. See: “A New Astronomy”, Popular astronomy , xix (1911), 594; “Report of the Meeting of the Association, held on Wednesday, December 28, 1910, at Sion College, Victoria Embankment, E. C.”, Journal of the British Astronomical Association , xxi (1911), 139–47; “Physics. Fresh Support for Professor Bickerton's Theory”, Knowledge , n.s., viii (1911), 324; O'Halloran Sylvester N. E. , “The Second Law of Thermodynamics and Professor Bickerton's Theory”, Knowledge , n.s., ix (1912), 361; McCarthy J. , “The New Astronomy”, Knowledge , n.s., vii (1911), 426; Raffety Charles W. , “The Spectroscopic Aspect of the Impact Theory”, Knowledge , n.s., ix (1912), 106; Monck W. H. S. , “The Collisions of Stars”, Observatory , xxxiv (1911), 202–3.

H. N. Russell thought that some of Bickerton's ideas were sound but they suffered from overdiscussion; Bickerton tried to explain too much with his theory (Russell to L. Spitzer, Jr, 18 May 1939, copy in Box 35, Russell papers at Princeton).

For the bibliographic history of this article see Science , cxlvii (1965), 757. The most comprehensive source of information on Chamberlin is Schultz Susan F. , Thomas C. Chamberlin, An intellectual biography of a geologist and educator (Ph.D. Dissertation, University of Wisconsin–Madison, 1976). See also the article by his son, Chamberlin Rollin T. , “Thomas Chrowder Chamberlin”, Biographical memoirs of the National Academy of Science , xv (1934), 307–407; Winnik H. C. , “Science and Morality in Thomas C. Chamberlin”, Journal of the history of ideas , xxxi (1970), 441–56; Mather Kirtley F. , “Chamberlin, Thomas Chrowder”, Dictionary of scientific biography , iii (1971), 189–91; articles by Leith C. K. Alden William C. Penrose R. A. F. Jr Charles Schuchert William D. MacMillan Bailey Willis Moulton F. R. , in Journal of geology , iv (May 1929); Willis Bailey , “Memorial of Thomas Chrowder Chamberlin (1843–1928)”, Bulletin of the Geological Society of America , xl (1929), 23–44.

Chamberlin's papers, including draft manuscripts, letters to and from him, and autobiographical notes, are preserved and easily accessible at the University of Chicago (Department of Special Collections, Joseph Regenstein library). As stated above (ref. 1), this collection will be cited as C-UC. There are also some letters (primarily dealing with administrative matters) at the University Archives of the University of Wisconsin, Madison; correspondence concerning research grants may be found at the Carnegie Institution of Washington (cited as CIW). Undoubtedly there are originals of letters from Chamberlin in the papers of many geologists and astronomers throughout the world; copies of most of these letters can be found in the Letterbooks in the Chamberlin collection at Chicago.

See anonymous article (signed “Fidus Achates”) on “The Washington Moultons, Forest Ray, ′94, and Harold Glenn, 1907”, in the magazine of the Albion College Alumni Association, Io triumphe , (2) xii (March 1947), 19–22; Tropp Henry S. , “Moulton, Forest Ray”, Dictionary of scientific biography , ix (New York, 1971), 552–3. Both the Io triumphe article and Tropp date Moulton's collaboration with Chamberlin from 1898, but the documents cited below indicate that it had begun at least as early as summer 1897. Io triumphe also confuses T. C. Chamberlin with his son Rollin.

One of Moulton's first publications advocated the presentation of the nebular hypothesis in elementary astronomy courses (cited in ref. 12).

Chamberlin T. C. , “Present Standing of the Several Hypotheses of the Cause of the Glacial Period”, Scientific American supplement , xxxii (1891), 13075–6.

Brush S. G. , The Kind of Motion We Call Heat (Amsterdam, 1976), §5·4. O'Hara J. G. , “George Johnstone Stoney, f.r.s., and the Concept of the Electron”, Notes and records of the Royal Society , xxix (1975), 265–76.

I am unable to locate a publication with this exact title; it is cited by Chamberlin in his 1897 paper (ref. 48, below), p. 658, and by Moulton in his 1900 paper (ref. 97, below), p. 111. Chamberlin's letter to Stoney G. J. , 6 September 1897, requesting a copy of this paper, indicates some bibliographic confusion (Letterbook IX, p. 428, C-UC).

Stoney G. J. , “Of Atmospheres upon Planets and Satellites”, Transactions of the Scientific Society of Dublin , vi (1897), 305–28; Astrophysical journal , vii (1898), 25–55. Chamberlin wrote to Stoney on 10 December 1897, thanking him for a copy of the paper and stating that he had seen an advance copy sent by Hale G. E. (Letterbook IX, p. 624, C-UC). In a letter to Van Hise C. R. , 30 November 1897, he says he saw this paper “yesterday” (Letterbook IX, p. 592, C-UC).

Chamberlin T. C. , “A Group of Hypotheses Bearing on Climatic Change”, Journal of geology , v (1897), 653–83, p. 656.

Ibid. , 656–7.

Ibid. , 657.

Ibid. , 660. This assumes a period of rotation of 23 hours 56·067 minutes. Another table gave the escape velocities for a rotation period of 1 hour 24 minutes (see text below).

Ibid. , 661. Letters from Chamberlin to Moulton, 10 September 1897, and to Whitney , 9 October 1897, indicate that there was some disagreement between Whitney and Moulton on the calculation of centrifugal force effects (Letterbook IX, pp. 434 and 476, C-UC).

Chamberlin's source of information about kinetic theory was a recent book by Risteen Douglas Allan , Molecules and the molecular theory of matter (Boston, 1895).

Darwin G. H. , “On the Precession of a Viscous Spheroid, and on the Remote History of the Earth”, Philosophical transactions , clxx (1879), 447–538.

Chamberlin , “A Group of Hypotheses” ( op. cit. , ref. 48), 666.

For further remarks about the bearing of the kinetic theory of gases on the origin of the Earth, see: Letter from Chamberlin T. C. Cook S. R. , 14 January 1899, in Letterbook XI, p. 181, C-UC; Chamberlin T. C. , The origin of the Earth (Chicago, 1916), ch. 1.

Chamberlin T. C. Comstock G. C. , 11 December 1895 (Letterbook VII, pp. 165–167, C-UC). The “recent English work” may be Gore Ellard J. , The visible universe (London, 1893), which includes an extensive discussion of Faye's work.

Ibid. .

Comstock G. C. Chamberlin T. C. , 13 December 1895 (Box I, folder 15, C-UC). For an account of Faye's theory and an explanation of how direct rotation might be produced he referred Chamberlin to Young C. A. , A text-book of general astronomy for colleges and scientific schools (Boston, 1895), 518–19.

Chamberlin , “A Group of Hypotheses …”, 668–9.

Darwin G. H. , “A Theory of the Evolution of the Solar System”, Internationale Wochenschrift , (30) iii (24 July 1909), 921–32 (p. 930). This article was used as a chapter in the 3rd ed. of Darwin's book The tides (1911).

Guili R. T. , “On the Rotation of the Earth Produced by Gravitational Accretion of Particles”, Icarus , viii (1968), 301–23. Harris A. W. , “An Analytic Theory of Planetary Rotation Rates”, Icarus , xxxi (1977), 168–74. Dr Harris kindly sent me the following comments on the Chamberlin-Moulton theory (letter of 15 July 1977): “It seems to me that they correctly point out that the retrograde rotation paradox is resolved by the effect of eccentricity: The simple cases with both planet and planetesimals in circular orbits as shown in their Figures 27 and 28 do not apply because there is no means for planetesimals to reach the planet embryo from significantly far away from the planet orbit. In their solution, they propose eccentric orbits for the planet embryos, while retaining circular orbits for the planetesimals. More recent works (e.g. V. S. Safronov, Evolution of the Protoplanetary Cloud, trans. 1972) favor the reverse situation: The planetesimals travel in more eccentric orbits than the planets. However, exactly the same geometry applies, and their Figure 30 is an excellent illustration of the effect which I attempt to illustrate in my Figure 1 and develop into an analytical theory in my paper. My result is as they suggest, that ‘the resulting rotation is likely to be relatively low, though the total force of impact be great’. In fact, I find that this mechanism produces rotation rates that are about an order of magnitude less than observed rotation rates, if one assumes eccentricities of planetesimals sufficient to deliver them to the planet orbits from distances midway in between. Satisfactory results can be obtained from this mechanism by assuming smaller (but non-zero) eccentricities, as was done by Giuli in his numerical theory”.

See also: Artemev A. V. Radzievsky V. V. , “The Origin of the Axial Rotation of the Planets”, Soviet astronomy AJ , ix (1965), 96–99 (translated from Astronomicheskii Zhurnal , xlii (1965), 124–8); Artemev A. V. , “Planetary Rotation Induced by Elliptically Orbiting Particles”, Solar system research , iii (1969), 15–21 (translated from Astronomicheskii Vestnik , iii (1969), 18–25).

Maxwell , “On the Stability of the Motion of Saturn's Rings”, essay awarded the Adams Prize at Cambridge University, 1 June 1857; revised version published in 1858, reprinted in The scientific papers of James Clerk Maxwell (Cambridge, 1890), i, 288–376. See Brush S. G. Everitt C. W. F. Garber E. W. , Maxwell on kinetic theory and statistical mechanics (Boston, 1978), §1–10 and ch. x.

Keeler J. E. , “A Spectroscopic Proof of the Meteoric Constitution of Saturn's Rings”, Astrophysical journal , i (1895), 416–27. This result was later confirmed by Deslandres H. , “Recherches Spectrales sur les Anneaux de Saturne”, Comptes rendus, Académie des Sciences, Paris , cxx (1895), 1155–8.

Roche E. , “Mémoire sur la Figure d'une Masse Fluide, Soumise à l'Attraction d'un Point Éloigné”, Mémoires de la Section des Sciences, Académie des Sciences et Lettres de Montpellier , i (1849), 243–62; i (1850), 333–48; ii (1851), 21–32; the application to Saturn's rings is on p. 258. On 6 March 1903, Chamberlin wrote to Comstock asking for the loan of Roche's work, which was apparently not available at Chicago (Letterbook XVI, p. 680; original at University of Wisconsin Archives, Astronomy Department General Correspondence series no. 7/4/2, box no. 7). See also Chamberlin's letter to the Librarian of Congress in 1903, Letterbook XVI, p. 681, C-UC.

Thomson William , “Review of Evidence Regarding the Physical Condition of the Earth”, British Association for the Advancement of Science, Address to Section A; Nature , xiv (1876), 426–31, reprinted in Popular lectures and addresses , ii (London, 1894), 238–72. Thomson William Tait P. G. , Treatise on natural philosophy (1912 edition, reprinted as Principles of mechanics and dynamics (New York, 1962)), i, part 2, 427–40.

Chamberlin T. C. , “Lecture, January 27, 1896” (typescript in Box 3, folder 17, C-UC).

Ibid. , 9–13.

See refs 4 and 25.

Chamberlin , “A Group of Hypotheses”, 668–70. There is a letter to Comstock, dated 30 November 1897, thanking him for criticisms and suggestions on this point in the paper (University of Wisconsin Archives, Department of Astronomy, General Correspondence, Series No. 7/4/2, box no. 5). Earlier Chamberlin had asked Moulton to calculate the heat that would be generated in the Moon by its self-compression (letter dated 30 July 1897, in Letterbook IX, p. 380, C-UC). See also Chamberlin Moulton , 24 November 1897 (Letterbook IX, p. 589, C-UC).

Chamberlin , “A Group of Hypotheses”, 676.

Chamberlin to Moulton, 24 November 1897 (Letterbook IX, p. 587, C-UC).

Moulton to Chamberlin, 25 November 1897 (Box 5, folder “Correspondence with F. R. Moulton”, C-UC).

Chamberlin to Van Hise, 22 January 1898 (Letterbook IX, p. 698, C-UC).

Chamberlin to Henry Holt, 27 January 1898 (Letterbook IX, p. 711, C-UC). See also Chamberlin Holt , 13 August 1898 (Letterbook X, p. 470, C-UC).

Geology , i: Geologic process and their results (New York, 1904).

See ref. 30.

Chamberlin to Barnard, 1 April 1898 (Letterbook X, p. 172, C-UC).

Science , n.s., ix (1899), 704–11; see ref. 25.

Chamberlin T. C. , “On Lord Kelvin's Address on the Age of the Earth as an Abode Fitted for Life”, Science , n.s., ix (1899), 889–901; x, 11–18. The manuscript was reviewed by Moulton before publication; see his letter to Chamberlin , 21 June 1899, in Box 5, C-UC.

Carroll Fenton Mildred , Giants of geology (Garden City, N.Y., 1945), 312–13.

Chamberlin R. T. , op. cit. (ref. 42), 351.

Chamberlin T. C. , op. cit. (ref. 80), 892–3.

Winnik H. C. , op. cit. (ref. 42).

For references see Brush , The temperature of history (New York, 1977). Others at this time favoured a cyclic cosmogony in order to avoid the heat death, for example Svante Arrhenius.

Chamberlin T. C. , op. cit. (ref. 80), 897.

It is not really correct to say that nineteenth-century biology required a definite amount of time for evolution, in excess of that allowed by Kelvin. Kelvin gave this impression in his writings, and later commentators have adopted it uncritically; see e.g. Hattiangadi J. N. , “Alternatives and Incommensurables: The Case of Darwin and Kelvin”, Philosophy of science , xxxviii (1971), 502–7. Huxley T. H. insisted that evolutionary biology only takes its time scale from geology and physics, and is not refuted by changes in that time scale; see his 1876 address, discussed by Brush , The temperature of history , 41.

Geikie J. , “A White-Hot Liquid Earth and Geological Time”, Scottish geographical magazine , xvi (1900), 60–67. This issue (February 1900) was received by the U.S. Department of Agriculture Library on 23 February 1900.

Chamberlin to Geikie, 13 March 1900 (Letterbook XII, p. 235, C-UC).

Moulton to Hale, 12 June 1899 (Box 23 of letters to Hale, at Yerkes Observatory).

Hale to Moulton, 13 June 1899 (Letterbook 7, p. 153, at Yerkes Observatory).

“I am glad to hear that there is some prospect of your remaining at the University. If you decide to do so I shall be glad to recommend you for promotion next year” ( Hale Moulton , 22 June 1899 (Letterbook 7, p. 187, at Yerkes Observatory)).

Moulton Hale , 3 January 1900 (Box 23 of letters to Hale, at Yerkes Observatory).

Only the title was published: “Laplace's ring nebular hypothesis”, Publications of the Astronomical and Astrophysical Society of America , i (1910), 98.

Moulton Hale , 15 January 1900 (Box 23 of letters to Hale, Yerkes Observatory).

“Your paper on the Nebular Hypothesis seemed to me to be all right and I therefore did not call. I hope you will not make any more changes in the galley proof than are really necessary as it is very expensive …” ( Hale Moulton , 20 February 1900 (Letterbook 8, p. 71, at Yerkes Observatory)).

Moulton F. R. , “An Attempt to Test the Nebular Hypothesis by an Appeal to the Laws of Dynamics”, Astrophysical journal , xi (1900), 103–30 (quotation from p. 130). For Chamberlin's comments on the manuscript of this paper (chiefly pertaining to the discussion of G. H. Darwin's explanation of the motion of Mars and Phobos) see his letter to Moulton , 19 January 1900, in Letterbook XII, p. 161, C-UC.

Moulton R. R. , Consider the heavens (Garden City, N.Y., 1935), 143–4.

Chamberlin Keeler , 30 January 1900 (copy from the tissue letter book, in Box I, folder 16, C-UC).

Chamberlin Keeler , 28 February 1900 (copy from tissue letter book, in Box I, folder 16, C-UC).

Chamberlin T. C. , “An Attempt to Test the Nebular Hypothesis by the Relations of Masses and Momenta”, Journal of geology , viii (1900), 58–73 (p. 58).

Cook S. R. , “On the Escape of Gases from the Planets according to the Kinetic Theory”, Proceedings of the American Association for the Advancement of Science , 1899, 120–1; “On the Escape of Gases from Planetary Atmospheres according to the Kinetic Theory”, Astrophysical journal , xi (1900), 36–43. Stoney G. J. , “Escape of Gases from Planetary Atmospheres”, Nature , lxi (1900), 515. Bryan G. H. , “On the Permanence of Certain Gases in the Atmospheres of Planets”, Report of the 69th Meeting of the British Association for the Advancement of Science , 1899, 634–5; “The Kinetic Theory of Planetary Atmospheres”, Nature , lxii (1900), 126.

Chamberlin , op. cit. (ref. 101), 59.

See ref. 39. Moulton ( op. cit. , ref. 97) stated that he used Darwin's “Isothermal-Adiabatic” sphere given on p. 25. A year later Anne Sewall Young (niece of the astronomer Charles Augustus Young) attacked the problem from the other end, using the present distribution of angular momentum to find the law of density of the initial nebula and showing that this leads to impossible results. See her paper, “Density of the Solar Nebula”, Astrophysical journal , xiii (1901), 338–43. Her work was apparently started under the direction of Moulton, who submitted it to Hale on 26 March 1901 with a letter saying that “In the light of these results many of Darwin's cease to have importance, and in my opinion, this might have been pointed out, but Miss Young felt timid about doing so” (Box 27, Yerkes Observatory).

Another way to express the discrepancy was suggested by Chamberlin : “If the matter of the solar system were expanded to some point beyond the orbit of Neptune in conformity to the laws of hydrodynamic equilibrium, and given the moment of momentum of the present solar system and allowed to contract by secular cooling, the centrifugal force in its equatorial portion would not become equal to the centrifugal force [and hence allow separation of a ring] until after it had contracted far inside the orbit of Mercury” (Letter to Moulton, 9 February 1900, in Letterbook XII, p. 189, C-UC (emphasis in original)).

Chamberlin , op. cit. (ref. 101), 71–72.

Ibid. , 72–73.

Keeler James E. , “The Crossley Reflector of the Lick Observatory”, Astrophysical journal , xi (1900), 325–49 (p. 348).

Chamberlin T. C. Moulton R. R. , “Certain Recent Attempts to Test the Nebular Hypothesis”, Science , xii (1900), 201–8 (p. 208) (published 10 August).

Chamberlin T. C. Moulton F. R. , “The Development of the Planetesimal Hypothesis”, Science , xxx (1909), 642–5. See also “Preliminary Notes on the Consequences of Collisions between Larger and Smaller Nebulae as a Possible Mode of Origin of the Solar System” (Box 5, C-UC).

Tropp Henry S. , “Moulton, Forest Ray”, Dictionary of scientific biography , ix (1974), 552–3. He had earlier remarked on the high speed of gases ejected in solar prominences; see “An Attempt to Frame a Working Hypothesis of the Cause of Glacial Periods on an Atmospheric Basis”, Journal of geology , vii (1899), 561.

Chamberlin Moulton , op. cit. (ref. 110), 644.

Huggins William , “The New Star in Auriga” (1892) and Turner H. H. , “The New Star in Gemini” (1903), both reprinted in The Royal Institution library of science—astronomy , ed. Lovell Bernard (New York, 1970), i, 378–89 and ii, 36–46. Shaler N. S. , Outlines of the Earth's history (New York, 1898), 42. Bickerton A. W. , “Some Recent Evidence in Favour of Impact”, Transactions of the New Zealand Institute , xxvi (1894), 464–76 and plate LII, and “Explosion of Stars”, Popular astronomy , xii (1904), 666–8. Campbell W. W. , “An Address on Astrophysics”, Popular science monthly , lxvi (1905), 297–318 (p. 308). Agnes Clerke, A popular history of astronomy during the nineteenth century (4th ed., London, 1902), 397–8. MacPherson Hector C. , A century's progress in astronomy (Edinburgh, 1906), 195. Waterfield R. L. , A hundred years of astronomy (London, 1950), 186–7. Monck W. H. S. , “New Stars and Shooting-Stars”, Observatory , viii (1885), 335–6. Gregory J. W. , The making of the Earth (London, 1912), 29. Clifford A. C. , “New Stars”, New Zealand journal of science and technology , viii (1925), 1–7.

Fiske John , The unseen world and other essays (Boston, 1876), 11–14. Tornow Eugen , “Die Entstehung des Sonnensystems”, Weltall , iii (1902), 69. Gore Ellard J. , “The Nebular Hypothesis”, Gentlemen's magazine , ccxciii (1902), 178–85. Halm Jacob E. , “On Professor Seeliger's Theory of Temporary Stars”, Proceedings of the Royal Society of Edinburgh , xxv (1905), 513–53, and “Some Suggestions on the Nebular Hypothesis”, ibid. , 553–61. Meyer Wilhelm Max , The Making of the World (Chicago, 1906), 43–45. Campbell W. W. , “The Problems of Astrophysics”, Congress of Arts and Science, St. Louis, 1904 (Boston, 1906), iv, 446–69 (p. 459). Snyder Carl , The world machine (London, 1907), 421–3. Arrhenius Svante , Worlds in the making (New York, 1908), 152. Bickerton A. W. , [Report of his remarks at meeting on 28 December 1910], Journal of the British Astronomical Association , xxi (1911), 139–42, and “The New Astronomy”, Knowledge , n.s., viii (1911), 362–7. Poincaré Henri , Leçons sur les Hypot hèses Cosmogoniques (2nd ed., Paris, 1913), p. LXIII.

Chamberlin T. C. , “On the Possible Function of Disruptive Approach in the Formation of Meteorites, Comets, and Nebulae”, Astrophysical journal , xiv (1901), 17–40 (p. 21).

For Roche's theory see ref. 65. In a memorandum dated 17 October 1901, Chamberlin noted that he had found somewhat similar ideas expressed in T. J. J. See's book, Researches on the evolution of the stellar systems (Lynn, Mass., 1896), i, 258 (Box 5, C-UC).

Nevertheless it is often stated that the Chamberlin-Moulton theory was first published in this paper.

Hovey E. O. , “Geology and Geography at the Denver Meeting of the American Association for the Advancement of Science”, Scientific American supplement (21 September 1905), lii, 21504–5.

Letterbook XIV, 213, C-UC.

Chamberlin Campbell , 18 October 1901 (Letterbook XIV, 254). Further letters to Campbell and Curtis H. D. , requesting photographs of nebulae, are in Letterbook XVII, 577, 690.

Hale G. E. , “Stellar Evolution in the Light of Recent Research”, Popular science monthly , lx (1902), 291–313 (p. 292). This is also quoted at the end of a “Memorandum of Chamberlin's Studies on the Fundamental Doctrines of Geology” submitted to the Carnegie Institution of Washington to support Chamberlin's application for a research grant.

Another astronomer thought that recent nova observations provided evidence for Chamberlin's theory of tidal disruption: Very Frank W. , “An Inquiry into the Cause of the Nebulosity around Nova Persei,” American journal of science , (4) xvi (1903), 49–60 (p. 55).

Pickering W. H. , “Entdeckung eines neuen Saturnmondes”, Astronomischen Nachrichten , clix (1899), 31–32, and “The Ninth Satellite of Saturn”, Harvard College Observatory annals , liii (1905), 45–73.

Crommelin A. C. D. , “Phoebe, Saturn's Ninth Satellite”, Journal of the British Astronomical Association , xv (1904), 32–35. One of Crommelin's colleagues immediately fulfilled his prophecy by suggesting a capture explanation: Lynn W. T. , “The Ninth Satellite of Saturn”, ibid. , 35–36.

Meyer M. W. , Die Welt der Planeten (Stuttgart, 1910), 60. Moreux Th. , Astronomy to-day (London, 1926), 134–5.

Pickering W. H. , “The Rotation of Jupiter's Outer Satellites”, Astronomy and astrophysics , xii (1893), 481–94; “Polar Inversion of the Planets and Satellites”, ibid. 692–3; “Explanation of the Inclination of the Planetary Axes”, Astronomical journal , xxii (1901), 56–57; “Direct and Retrograde Rotation of the Planets”, Astronomische Nachrichten , clxiv (1904), 201–4, and “Planetary Inversion”, Publications of the Astronomy and Astrophysics Society of America , read 1905 (pub. 1910), i, 250–1. Stratton F. J. M. , “Planetary Inversion”, Monthly notices of the Royal Astronomical Society , lxvi (1906), 374–402. Redman L. A. , Professor Montgomery's discoveries in celestial mechanics (San Francisco, 1919). In reply to a criticism of Moulton, Pickering insisted that his theory is not the same as Kirkwood's (mentioned above, Section 2). See “Note on the Evolution of the Solar System”, Astrophysical journal , xxii (1905), 354–5, with Moulton's reply and Pickering's rejoinder on following pages.

In his long article, “An Attempt to Frame a Working Hypothesis of the Cause of Glacial Periods on an Atmospheric Basis”, Journal of geology , vii (1899), 545–84, 667–85, 751–87, Chamberlin T. C. made frequent use of the results presented by Arrhenius in “On the Influence of Carbonic Acid in the Air upon the Temperature of the Ground”, Philosophical magazine , (5) xli (1896), 237–76. But later he protested to C. G. Abbot that he had never favoured Arrhenius's theory of glaciation, and had been misled by Arrhenius's results (Chamberlin to Abbot, 3 May 1913, in Secretarial Records of C. D. Walcott, record number 45, box 31, Smithsonian Institution Archives).

Arrhenius Svante , “Zur Kosmogonie”, Archives Néerlandaises des sciences exactes et naturelles , (2) vi (1901), 862–73, and Lehrbuch der Kosmischen Physik (Leipzig, 1903), 221–30.

Arrhenius Svante , Worlds in the making: The evolution of the universe (New York, 1908), 148, 193–4, 206–10. His cosmogony is not even mentioned by many of his biographers, e.g. Walker James , “Arrhenius Memorial Lecture”, Journal of the Chemical Society (1928), 1380–401; Snelders H. A. M. , “Arrhenius, Svante August”, Dictionary of scientific biography , i (1970), 296–302. The account by his grandson makes it appear that his theory was monistic; see Arrhenius Gustav O. S. , “Svante Arrhenius' Contribution to Earth Science and Cosmology”, Levnadsteckningar över K. Svenska Vetenskapsakademiens ledamöter , clvii (1962), 345–59.

For supporters of the Arrhenius theory see: Henkel F. W. , “The Birth and Death of Worlds”, Knowledge , n.s., vi (1909), 6–8; Kaempffert W. , “The Life of a Star”, Outlook , xcii (1909), 707–16; Musson Balfour W. , “Development in the Stellar Universe”, Journal of the Canadian Royal Astronomical Society , iii (1909), 5–27; Becher E. , Weltgebäude, Weltgesetz, Weltentwicklung (Berlin, 1915), 284, 289; Snyder C. , op. cit. (ref. 3), 423; Amaftunsky A. , “Kosmogoniya”, Izvestiya Russkago Astronomischekaga Obshestva , xv (1909), 135–44 (cited in Astronomische Jahresbericht , (1909)); Busco Pierre , L'évolution de l'astronomie au XIX^e siècle (Paris, 1912), 69–70.

Lowell Percival , The solar system (Boston, 1903), 118–30. For earlier remarks favourable to the nebular hypothesis, see Mars (Boston, 1895), 4.

Lowell Lawrence A. , Biography of Percival Lowell (New York, 1935), 128; Marsden B. G. , “Lowell, Percival”, Dictionary of scientific biography , viii (1973), 520–3.

Lowell Percival , “Mars as the Abode of Life”, Science , xxx (1909), 338–40. The controversy between Lowell, See and Moulton is summarized by Hetherington Norriss S. , “The Simultaneous ‘Discovery’ of Internal Motions in Spiral Nebulae”, Journal for the history of astronomy , vi (1975), 115–25. See also Lowell's refutation of the planetesimal hypothesis applied to satellite motions, in “Planets and their Satellite Systems”, Astronomische Nachrichten , clxxxii (1909), 97–100. His own theory was presented in The evolution of worlds (New York, 1909), 24–30, 142–51, and in a popular article, “The Revelation of Evolution: A Thought and its Thinkers”, Atlantic Monthly , civ (August 1909), 174–83. For its detailed application to individual planets see “The Genesis of the Planets”, Journal of the Royal Astronomical Society of Canada (1916), 281–293.

Rolston William E. , “Planetology”, Nature , lxxxiv (1910), 99–100. Chas. Lane Poor, review in Science , xxxi (1910), 506–7. Anonymous review in Living age , cclxv (11 June 1910), 699–700.

See T. J. J. , “Recent Discoveries Respecting the Origin of the Universe”, Atlantic monthly , lxxx (1897), 484–92.

Clerke Agnes , Modern cosmogonies (London, 1905), 44. See T. J. J. , “Miss Clerke's Modern Cosmogonies”, Popular Astronomy , xiv (1906), 313–14.

See T. J. J. , “Significance of the Spiral Nebulae”, Popular astronomy , xiv (1906), 614–16.

See T. J. J. , “The Planar Arrangement of the Planetary System”, Nature , lxxxi (1909), 275; “On the Cause of the Remarkable Circularity of the Orbits of the Planets and Satellites and on the Origin of the Planetary System”, Astronomische Nachrichten , clxxx (1909), 184–94, and “The Laws of Cosmical Evolution and the Extension of the Solar System beyond Neptune”, Publications of the Astronomical Society of the Pacific xxi (1909), 60–71.

See T. J. J. , “Origin of the Lunar Terrestrial System by Capture with further Considerations on the Theory of Satellites and on the Physical Cause which has Determined the Directions of the Rotations of the Planets about their Axes”, Astronomische Nachrichten , clxxxi (1909), 365–86; “The Past History of the Earth as Inferred from the Mode of Formation of the Solar System”, Proceedings of the American Philosophical Society , xlviii (1909), 119–25. A comprehensive exposition of See's theory may be found in his book Researches on the evolution of the stellar systems , ii: The capture theory of cosmical evolution (Lynn, Mass., 1910). Qualitatively similar theories had been proposed earlier by Taylor R. B. (1898, 1903) and Gareis A. (1901).

The following supported See's theory: Numford N. W. , “A Question on the Capture Theory”, Popular astronomy , xx (1912), 228–32; Dean J. C. , “From Whence Came the Earth?”, Westminster review , clxxx (1913), 635–44; Wallace Russel Alfred , letter to Webb W. L. , 28 October 1913, in See Papers, Library of Congress; Henkel F. W. , “New Theories of the Evolution of Stellar System”, Scientific progress in the twentieth century , v (1910), 82–90 and “New Methods in Astronomy, Their Application to the Evolution of our System”, Knowledge , vii (1910), 350–4; Kerfoot J. B. , World to-day , xxi (1912), 1665–76.

Birkeland Kr. , “Sur l'Origine des Planètes et de leurs Satellites”, Comptes rendus, Académie des Sciences, Paris , clv (1912), 892–5, “The Origin of Worlds”, Scientific American supplement , lxxvi (1913), 1, 8–9, 12, 20–21, 32.

Chamberlin T. C. , “The Origin of Ocean Basins on the Planetesimal Hypothesis”, Bulletin of the Geological Society of America , xiv (1903), 548 (abstract); a similar account appeared on pp. 22665–6 of Hovey's E. O. report on “The Annual Meeting of the Geological Society of America, and Geology and Geography at the Convention of the American Association for the Advancement of Science”, Scientific American supplement , lv (1903), 22646–8, 22665–7. See also Science , xvii (1903), 300–1.

The discussion was reported following the account of Chamberlin's talk, under the title “The Origin of Ocean Basins on the Planetessimal [sic] Hypothesis”, Science , xvii (1903), 300–1. Chamberlin soon dropped the extra “s”; as he explained in a letter to Fairchild H. L. , 9 June 1903, “The analogy of ‘infinitesimal’ permits the omission of one ‘s’, and this is in the line of simplification and progress” (Letterbook XVII, 269, C-UC).

Quoted from Science , xvii (1903), 301. For Merrill's later views on this subject see “The Composition of Stony Meteorites Compared with that of Terrestrial Igneous Rocks and Considered with Reference to their Efficacy in Worldmaking”, American journal of science , (4) xxvii (1909), 469–74.

Science , xvii (1903), 301.

R. A. Millikan to T. C. Chamberlin, 23 December 1903 (Box 5, C-UC).

Copy in Box 4, folder 20, C-UC. A copy of Walcott's reply and other correspondence may be found in the file of Chamberlin correspondence at the Carnegie Institution of Washington (hereafter abbreviated CIW).

This is probably the undated “Memorandum of Chamberlin's Studies on the Fundamental Doctrines of Geology” at CIW (copy in Box 5, C-UC); however, that Memorandum contains a quotation from Hale's G. E. article in the February 1902 issue of Popular science monthly (see ref. 121), so one would have to assume that this article was available to Chamberlin before the nominal publication date in order to accept this identification.

“An inquiry into the fundamental problems of geology as set forth in detail in a communication to Trustee C. D. Walcott under date of Jan. 23^d 1902 & other letters”, Application for Grant in Aid of Research, 2 January 1902, in Chamberlin file at CIW (received 6 January 1903).

Chamberlin T. C. Walcott C. D. , 10 January 1903, in Chamberlin file at CIW. The letter begins, “Yours of the 6th announcing that my application for a grant has been approved, is at hand.”.

Ibid. , 1. Correspondence on Hoskins's work for the project may be found in Letterbooks XVI and XVII, and in Addenda Box II, folder 4, C-UC. See also “Scheme for Work under the Carnegie Institution”, 7 January 1903, in folder of miscellaneous notes and calculations, Box 5, Chamberlin papers at Chicago.

Hoskins Miller Leander (1860–1937) had taught civil engineering and mechanics at Wisconsin from 1885 to 1892, and was professor of applied mathematics at Stanford from 1892 to 1925.

Correspondence with Slichter on this problem may be found in Letterbooks XIV, XVI and XVII, and Addenda Box III, folder 5, C-UC.

Slichter Sumner Charles (1864–1946) was professor of applied mathematics at Wisconsin, with a special interest in the motion of underground water.

Lunn had been mentioned in Chamberlin's earlier letter to Walcott of 23 January 1902, as “a rising young mathematician of remarkable promise”.

Lunn Constant Arthur (1877–1949) taught applied mathematics at Chicago starting in 1903, promoted to professor in 1923.

Walcott Chamberlin , 28 January 1902; Chamberlin Walcott , 27 February 1903; Chamberlin Woodward R. S. , 13 October 1908, all at CIW. “Proposition relative to the Grant of the Carnegie Institution for Investigations in the Fundamental Doctrines of Geology”, apparently a memorandum to President Harper, copy in Box 4, folder 20, C-UC.

Woodward R. S. Chamberlin T. C. , 8 March 1910, at CIW.

Chamberlin Woodward , 14 January 1910; 11 February 1910. Woodward Chamberlin , 21 January 1910, and 8 March 1910. (All at CIW).

See below, ref. 170.

Walcott C. D. Chamberlin T. C. , 25 January 1902; Chamberlin Walcott , 28 January 1902; Walcott Chamberlin , 12 March 1902 (on committee appointments). Chamberlin Walcott , 14 June 1902 (on scientific journals). (All at CIW).

Woodward R. S. Chamberlin T. C. , 16 November 1906; Chamberlin Woodward , 24 November 1906. For detailed discussion of the Carnegie Institution's change in policy see Reingold N. , “National Science Policy in a Private Foundation: The Carnegie Institution of Washington, 1902–1920”. Reingold's interpretation is that Woodward wanted the Carnegie Institution to be not merely a “disbursing agency” but a real participant in research.

Chamberlin Woodward , 6 September 1909 and 19 October 1909; Woodward Chamberlin , 8 September 1909 and 21 October 1909 (on hiring Chamberlin's son Rollin); Moulton F. R. Woodward , 3 August 1905 (on hiring Moulton's brother). (All at CIW).

Woodward Chamberlin , 3 January 1910 and 21 January 1910; Chamberlin Woodward , 14 January 1910 (the denial has “wrecked my plans” to recruit a new collaborator). (All at CIW).

Chamberlin Moulton , 12 January 1903 (Letterbook XVI, 404–6, C-UC).

Chamberlin Moulton , 28 November 1903, in Letterbook XVII, 778; Moulton Chamberlin , 20 December 1903, and 8 February 1904, in Box 5, folder “Correspondence with F. R. Moulton”, C-UC.

Chamberlin Hayes C. W. , 24 February 1904 and 14 March 1904, in Box 5, C-UC.

“Memorandum on Original Announcement of the Planetesimal Hypothesis”, 4 October 1928, 1 (Box 5, C-UC).

Chamberlin Newcomb , 17 March 1904; Chamberlin Becker , 18 March 1904 (both in Box 5, C-UC); Chamberlin Gilbert , 18 March 1904 (Letterbook XVIII, 102); Chamberlin Newcomb , 18 March 1904 (Letterbook XVIII, 105). The original of the letter to Newcomb is in the Newcomb papers at the Library of Congress, container #19.

Chamberlin Moulton , 28 April 1904 (Box 5, C-UC).

Chamberlin Becker , 11 April 1904 (Box 5, C-UC).

Becker G. F. , “Kant as a Natural Philosopher”, American journal of science , (4) v (1898), 97–112.

Becker G. F. , “Present Problems of Geophysics”, Science , xx (1904), 545–56.

Chamberlin Moulton , 28 April 1904, p. 2. See also Chamberlin to Gilbert, 11 April 1904.

Chamberlin Moulton , 2 March 1904, in Box 5, C-UC; also Letterbook XVIII, 55.

Chamberlin T. C. , “Fundamental Problems of Geology”, Carnegie Institution yearbook for 1904, 195–258 (pub. 1905). Similar remarks are found in the Chamberlin-Salisbury text (ref. 2), ii, 51, 55.

Chamberlin Moulton , 16 May 1904 (Letterbook XVIII, 285).

Chamberlin , “Fundamental Problems”; Chamberlin Salisbury , op. cit. (ref. 2), ii, 58.

Moulton to Chamberlin, 19 May 1904, in Box 5, C-UC.

Moulton to Chamberlin, 24 May 1904, in Box 5, C-UC.

Chamberlin to D. C. Gilman, 30 September 1904 (Chamberlin file, CIW).

Woodward to Wolcott, in Chamberlin file at CIW.

Ibid. Hill William George (1838–1914) was the leading mathematical astronomer in the United States at the time, equalled only by Simon Newcomb; he was appointed to the Rutherford chair of astronomy at Columbia (where Woodward was Dean of the College of Pure Science) but resigned because there were so few qualified students to teach.

“Fundamental Problems of Geology”, Yearbook No. 3, 195–258. The fact that this is called the “Yearbook for 1904” has obscured the fact that Chamberlin's paper was not actually published until 1905.

Moulton F. R. , “On the Evolution of the Solar System”, Astrophysical journal , xxii (1905), 165–81.

Ibid. , 168. The details of these calculations were never published. He mentioned the difficulty of the work in a letter to Woodward, 3 August 1905 (Chamberlin file at CIW). The results were said to be qualitatively favourable to the hypothesis in Moulton's “Report”, Carnegie Institution yearbook No. 4 for 1905 (1906), 186–90; see also letter from Chamberlin to Woodward, 28 October 1905, in Chamberlin file at CIW. In his report for 1906, Moulton stated that he had computed the orbits of material ejected from the Sun in 48 cases, following them for about five years each time; in most cases the disturbing star's closest approach to the Sun was 5 A.U. See “On the Probability of a Near Approach to Two Suns and on the Orbits of Material Ejected from them under the Stimulus of their Mutual Tidal Disturbances”, Carnegie Institution yearbook No. 5 for 1906 (1907), 168–9. But three years later Moulton reported that his work on this problem was not yet complete (“Inquiry into the Fundamental Problems of Geology”, Carnegie Institution Yearbook No. 8 for 1909 (1910), 225–6). I have not made a systematic search for possible later publications since Moulton himself told Russell H. N. that “in nearly 30 years I have written only three times on the Planetesimal Hypothesis, and in two of those three times the material appeared in my ‘Introduction to Astronomy’” (Moulton to Russell, 6 June 1929, in Box 33, Russell H. N. papers, Princeton University Library).

Scheiner J. , “Ueber das Spectrum des Andromedanebula”, Astronomische Nachrichten , cxlviii (1899), 325–8; Astrophysical journal , ix (1899), 149–50.

Moulton , “Evolution of the Solar System”, 169.

P. 172.

Ibid. .

Moulton , “An Attempt to Test the Nebular Hypothesis …” (ref. 97), 108.

The rotation periods for the planets in order of mass are: Jupiter 9^h 50^m 30^s; Saturn 10^h 14^m; Neptune 16^h; Uranus 11^h [retrograde]; Earth 23^h 56^m 4^s; Venus 243^d [retrograde]; Pluto 6^d 9^h; Mars 24^h 37^m 23^s; Mercury 59^d.

P. 175. According to Newtonian gravitational theory the period of revolution of a satellite varies inversely as the square root of the mass of the primary.

See ref. 125.

Turner H. H. , as reported in “A Vital Change in our Theory of the Solar System”, Current literature , xlvii (1909), 445–7. Eddington A. S. regarded the discovery of a retrograde 8th satellite of Jupiter as confirmation of Pickering's theory; see “Some Recent Results of Astronomical Research” (1909), in The Royal Institution library of science—astronomy (ref. 113), ii, 97–112.

P. 181.