In search of James Croll: archives, genealogy, publications and other resources

: Source materials for investigating the life of James Croll are examined and collated. This is organised around the topics of: Croll ’ s Autobiographical sketch and the Memoir of his life and work , both contained within the volume produced by James Campbell Irons; publications by Croll; aspects of his genealogy; manuscript sources in publicly accessible archives and in private ownership; and other published sources.

• The Autobiographical sketch and Memoir • Publications by James Croll • Genealogyvital, monumental and related records (wills, probate, etc.) • Manuscript sourcesarchival, including related digital resources • Manuscript sources for sale and in private ownership • Published sourcesincluding catalogues, thesis and digital resources This arrangement might be considered unconventional in that it does not proceed from primary manuscript sources to secondary published ones. This is a consequence of the variety of elements under consideration and, hence, this is not a straightforwardly bibliometric study. All references are contained within section 9, which is sub-divided in terms of manuscript sources (sections 9.1 and 9.2), followed by a list of Croll's publications (section 9.3). The latter precede the list of relevant published materials that are not authored by Croll (section 9.4).

The Autobiographical sketch and Memoir
An essential starting point for those interested in a considered study of Croll is the Autobiographical sketch of James Croll LL.D., F.R.S., etc. with memoir of his life and work (Irons 1896). The substantial (553-page) compilation of commentary and correspondence, together with Croll's own Autobiographical sketch, was a labour of adulation by his solicitor friend, James Campbell Irons (1840Irons ( -1910, the son of David Irons, the Perth grocer who had inducted Croll into the ways of selling tea (one of Croll's early careers).
Of great importance is the brief 33-page Autobiographical sketch and the 'Prefatory note', which Croll had dictated to his wife prior to his death (Croll 1887;Edwards 2021). The Sketch contains information on his family history, upbringing, schooling, his many jobs and homes (Edwards & Robinson 2021), the joys and frustrations of his scientific life and the central importance to him of religion.
The Memoir has extensive portions of biographical material either copied or paraphrased from the Autobiographical sketch by Irons. In addition, there is verbatim reproduction of a large number of letters which passed between Croll and his correspondents, both scientific (e.g., Charles Darwin, Joseph Hooker, John Tyndall) and personal (and often religiouse.g., James Morison, Osmond Fisher)for which some of the originals are to be found in the British Library (sections 4 and 9.1.3). Irons also included letters of reminiscence and obituaries by William Thomson (later Lord Kelvin) and John Horne, Croll's friend and colleague at the Geological Survey in Edinburgh (Thomson 1891;Horne 1892).
The choice of publisher for the volume -Edward Stanford of Charing Cross, Londonwas probably linked to the fact that Croll had published two books with them, including one completed only weeks before his death (Croll 1885b(Croll , 1890b).

Publications by James Croll
Between 1854 and 1890, Croll published around 100 items. His publishing career was bookended by two religiously orientated philosophical volumes (Anon. [=Croll] 1857, 1890) and included a further three books (Croll 1875a(Croll , 1885b(Croll , 1889c, of which the first is the monumental Climate and time in their geological relations: a theory of secular changes of the Earth's climate. The American edition of Climate and time (with the same pagination of the main text as the British edition) was reprinted without change in 1885 by Adam and Charles Black of Edinburgh. This last company, in 1885, also produced Discussion of climate and cosmology (Croll 1885b), although the identical version published by Edwards Stanford of London is seen more commonly.
An incomplete list of Croll's publications first appeared in the obituary produced by John Horne (1892) and it was reproduced by Irons in his Memoir without specific acknowledgement. In neither case were volume or page numbers included, nor, often, were full titles and other publication details. Where possible, this information has been included in section 9.3. At the end of Horne's inventory, he said that 'The list of Dr Croll's scientific publications from 1861 to 1883 was prepared at the latter date for a special purpose. I am indebted to the kindly aid of Mr Bennie of the Geological Survey of Scotland for completing the list.' That 'special purpose' was presumably the memorial submitted to the 'Lords of the Committee of the Council on Education, Science and Art Department' in an effort to secure an enhanced pension (Edwards & Robinson 2021). James Bennie  had previously worked in a paper factory and had received kindly encouragement from Croll for his fossil collecting and other geological investigations (Anon. 1901).
Croll published most frequently in the Philosophical Magazine (42 times), followed by Nature (21) and the Geological Magazine (14). The full title of the first of these was The London, Edinburgh, and Dublin, Philosophical Magazine and Journal of Science, of which Series 4 appeared in 1851-1875 and Series 5 from 1876 to 1900. Each series consisted of 50 volumes. It has always been published by Taylor & Francis or predecessor companies. Its appeal 'was predicated on its independence: free of the bureaucracy that attended the learned society, as well as the strictures on having to present papers before publication, Philosophical Magazine was able to present itself as a nimble operator and rapid route to publication' (Clarke & Mussell 2015, p. 323). The current iteration of the journal, Series 8, is titled The London, Edinburgh, and Dublin, Philosophical Magazine and Journal of Science: A Journal of Theoretical Experimental and Applied Physics.
As was common during the 19th Century, a number of Croll's papers were published simultaneously in other journals. For instance, Croll (1880c), in Nature, also appeared in the Geological Magazine and the American Journal of Science and Arts. Instances of simultaneous publication are not listed as separate items in section 9.3. In some cases, the papers were split between different issues of the same journal (e.g., Croll (1865c) on glacial submergence appeared in the 2nd and 9th December issues of The Reader).

Genealogy
Croll's keen sense of family and place have been explored elsewhere (Edwards & Robinson 2021).
The importance of his family connections was demonstrated on the first page of the Autobiographical sketch (Croll 1887), where he spoke of siblings, parents and predecessors and his consultation of the baptismal register for Cargill parish, which had enabled him to trace his (paternal) ancestors to the middle of the 17th century. Using a combination of dispersed statements within Irons's text and genealogical data on births, marriages and deaths (e.g., accessible via FamilySearch (2021) and Ancestry (2021), including census data for the periods 1841-1901), it has been possible to construct a family tree, which extends back to approximately the first third of the 18th Century ( Fig. 1). It is a little unusual for the records of this era to record so few children or to show marriages from beyond relatively local areas. Records of children who died as babies or even in infancy were not always recorded; while Croll's brief residence in Elgin as a tea merchant, and where he met his wife, was perhaps influenced by the fact that his mother's family came from that town.
The cross-matching of historical sources can, of course, be informative. An example is provided by Croll's Civil Service files associated with recruitment to the Geological Survey of Scotland. There he named John Findlay of Elgin and William Logan of Glasgow as referees (CSC 11_73-004), though without further comment other than their addresses. John Findlay was, in fact, his wife's brother-in-law (Fig. 1), and William Logan, 'much esteemed in Glasgow for the interest he took in the temperance and other social reforms' (Croll 1887, p. 27), was a director of the Safety Life Assurance Company and had offered Croll a job in 1853 as agent's assistant after the failure of his temperance hotel in Blairgowrie.
The sources for changes in names of the Croll family (Croyl → Croil → Croll), aspects of family life evident in censuses, wills and probate ('confimation') records are explored in Edwards & Robinson (2021) and listed in section 9.1. Additional information comes from Croll's headstone in Cargill churchyard (Fig. 2). Here, Croll's father is named 'David Croll (Croyl)', whereas his surname had been 'Croil' according to his declaration of 1854 (CSC 11/73, pp. 021-23) used by James in connection with his recruitment to the Geological Survey of Scotland. Irons (1896, p. 488) talked of Croll's 'tombstone which he had been at some pains to get erected himself', yet the probable monumental mason wrote to Croll from Cargill on 25 April 1876 (Irons 1896, p. 308): SIR,-I got the inscription that you sent me to put on the tombstone, and I send it to you as you wished to know it for the putting on of your brother's name…. If you would send me the inscription you want put on the stone as soon as convenient, I will try and get it done as soon as I possibly can, and in so doing you will oblige,-Yours truly, JOHN FENWICK.
The contents of this letter would seem to be more correctthat is, an inscription for James's brother David who died 28 February 1876. The nature of the lettering on the stone (larger size for the upper half and smaller and less spaced text in the basal portion as more names were added) would suggest that the stone was augmented rather than newly erected at James's instigation. Furthermore, the back of the stone (Fig. 2) bears the date 1787 and the initials of three individuals -Alexander Croyl, his wife Isabel Bisset, along with their son, David Croll (Croyl). The stone can surely be taken as inscribed, being by Alexander Croyl and Isabel Bisset in memory of their children who died in infancy.
Alexander and Isabel would have had the stone erected as a family grave in 1787. The omission of the initials of the siblings of their son David (i.e., Mary, Christian and James) was likely because of their deaths prior to 1787, though all are mentioned on the face of the stone. Figure 1 Extended family chart for James Croll and his wife Isabella Macdonald. James Croll's position within the chart is accentuated by shading. Note that Isabella Macdonald appears twice (middle row, left)as James's wife and as a member of the Macdonald familyas does Janet Ellis, his mother (second row down, to left and in the centre). Abbreviations: b = baptismal or birth date; m = marriage date; d = death or burial date. As is always the case with such records, it is important to note that it has not been possible to verify all links.
Museum, Edinburgh University, the University of Cambridge and The National Archives. Lesser quantities of material are in institutional and private hands. Publicly accessible material is listed in section 9.1.
The most diverse range of documents is that in the British Library collections. A number of these are clearly associated with Irons's Memoir and described as 'Letters, chiefly from men of science to James Croll…with letters to his biographer'. These represent communications from an astonishing list of notables, including Charles Darwin, Joseph Hooker, John Tyndall, Charles Lyell, Alfred Russell Wallace, Francis Galton, Charles Wyville Thomson and Alexander Agassiz. The 'bundle' of documents was consigned under the name of Michelmore and sold as Lot 189 by Sotheby's in 1924(Francesca Charlton-Jones, pers. comm. May 2016. The preceding lot is a collection of eight autograph letters to Charles Darwin from Croll, dated 1868-1875, 'on geological topics' (Sotheby, Wilkinson & Hodge 1924). In addition, the British Library houses the papers associated with the Royal Literary Fund for writers in financial difficulties (Edwards & Robinson 2021;RLF 2021).
The British Geological Survey archive consists of a mixture of copies of correspondence on matters such as Croll's appointment, medical situation and retirement, as well as a series of letters from Croll to his work colleague Benjamin Neeve Peach . The 28 letters to Peach span the period 1871-1884 and vary from routine work affairs to personal observations, which shed some light on Croll's persona (Edwards & Robinson 2021).
The material on Croll within the Sir Archibald Geikie Archive of Haslemere Educational Museum covers correspondence Geikie (1835Geikie ( -1924 when both Director of the Geological Survey in Scotland (1867-1882) and of Great Britain (1882-1901. Copies of more than 60 letters concerning Croll (most written to him) survive for the period between 1869 and 1885. They mainly consist of outgoing official correspondence, but also demonstrate that Geikie confided in Croll when it came to some colleagues, and that he also worked assiduously in attempting to alleviate Croll's pension and financial problems.
The Edinburgh University Library, Special Collections, has records spread across two collections. The largest group, 22 letters, sent from 1865 to 1866 to Sir Charles Lyell (1797Lyell ( -1875 by James Croll, are contained within . These are mainly of a scientific nature and cover such topics as the temperature of space, the velocity of light, the sun's heat on earth at different times of the year, orbital variations, oceanography and ice accumulation. There are also letters from Croll to Archibald Geikie (Coll-74) concerning the former's financial situation and a letter from Charles Darwin to Geikie saying that he had signed the nomination certificate of Croll for Fellowship of the Royal Society 'with real pleasure' (Coll-74;Edwards 2021).
It is possible to access 16 letters between Charles Darwin and James Croll via the Darwin Correspondence Project (University of Cambridge 2021) housed at the University of Cambridge. Some of these (as copies or originals) are to be found in archives listed in section 9.1 or reproduced in Irons (1896). In addition, the Darwin Correspondence Project also enables online searches that mention Croll in letters and publications. The transcript letters between Darwin and Croll, and dated 1868-1881, are concerned with topics such as time, denudation, alternating glaciations in the Northern and Southern Hemispheres and glacier motion. There are also 13 letters sent by Croll to Charles Darwin's astronomer son, George Howard Darwin (1845-1912, within the Darwin Archive of the University. The National Archives holds documents submitted to the Civil Service Commission in association with Croll's recruitment to the Geological Survey of Scotland in 1867, with later inserts. This provides useful information on his previous employments, family issues (especially the surname change) and his examination failure. There are 28 pages of data, including some duplicate information. Most, if not all, of the material (especially the forms and a letter) is not in the hand of Croll. The aspiring geological administrator sometimes used others with neater handwriting to write on his behalf.

Manuscript sources for sale or in private ownership
A number of documents relating directly to Croll have been sold via auction houses and booksellers. These institutions are reluctant to pass on information concerning purchasers and it is difficult to determine where such material now resides. Nevertheless, it is of interest to know what is available at the time of writing, or was previously available, and some of these sales are listed in section 9.2. This writer has also been able to obtain a small number of documents and the opportunity is taken to summarise these. These include two presentation copies of Climate and time (Croll 1875a). The first is the actual copy sent to Charles Wyville Thomson of the Challenger expedition. It is inscribed 'To Professor Wyville Thomson LL.D., FRSfrom the Author' (Fig. 3) and was acknowledged by Thomson from Ascension Island on 2 April 1876 (British Library, Add MS 41077, ff. 86, 87;transcribed in Irons 1896, pp. 308-09). The book subsequently passed into the library of Thomson's expedition colleague and editorial successor, Sir John Murray, and bears Murray's Challenger bookplate. The second volume contains a simple inscription -'With the author's kind regards'and its owner was a resident of Alford, Aberdeenshire, with family farming connections in Angus.
The writer also has a collection of five offprints sent to Joseph Henry (1797-1878), Director of the Smithsonian Institute. These date from 1870 to 1879, and one of them (Croll 1875c) is inscribed 'To Professor Henry with the author's compliments'. The offprints were accompanied by an advertising leaflet for Climate and time with the words 'D. Appleton of New York', in Croll's hand, written beneath the printed details of the British publishers (Daldy, Isbister & Co., 56, Ludgate Hill, London).
Collections of papers from bound volumes, reported as being owned by Croll, were available for sale in 2004 from Maggs Brothers, London, and 2017-2021 from Jeff Weber Rare Books of California, USA, and Montreux, Switzerland. Advertised as being 'From the collections of James Croll', they seem to have originated from John Turton Antiquarian Books of Crook, Co. Durham, who bought them around the year 1990 from the Hodgson's Rooms division of Sotheby's (Ben Bainbridge, pers. comm. April 2020). One of the volumes (in the writer's ownership) comprises 25 offprints with 'Pamphlets -Foreign -Vol. III' in gold lettering on the spine. The offprints are dated 1879-1880 and cover German, Scandinavian and Swiss geology and geomorphology, and they are listed (in a hand that is not that of Croll) by author and either journal or summary article title, at the start of the volume. Many of the papers are inscribed with a dedication to Croll, including those by Gottlieb Michael Berendt (1836-1920), Albrecht Penck (1858-1945 and Alfred Gabriel Nathorst . Not all papers have been cut, especially those by the Swiss geologist Eugène Renevier , which may indicate that Croll was disinterested or unwilling to read geological papers in French. This volume would appear to be a companion to another consisting of 41 offprints published in 1855-1874 on subjects such as climate, light, radiation, astronomy, climatology, glaciers and oceanography, available from Jeff Weber Rare Books. These include papers by William Thomson (Lord Kelvin;1824-1907  Irons volume contains an inscription to a Mr James G. Lunn of Paisley, with two items pasted into the front pages. The first is a handwritten excerpt from the Proceedings of the Perthshire Society of Natural Science for 1891, recording the death of 'Dr Croll, whose fame as a man of science is known to all, did honour to the Society by allowing himself to be enrolled as an honorary member.' The second is a letter from a Douglas Butter of St Martins, Burghmuir, Perth, to the eponymous Mr Lunn and dated 1 December 1946. Butter said: I expect you will have been at Cargill Churchyard to see the stone. If you know Thomas Macqueen of Souter & Macqueen joiners Perth, who is an elder in St Leonard's in the Fields, you could have a talk with him. He had heard Mr. Baxter talk of the famous man who belonged to Wolfhill. The Rev. George Chalmers Baxter (1843-1908 was the Free Church minister of Cargill. The letter indicates that Croll's gravestone was clearly known locally in 1946, even if its location was subsequently 'lost' until it perhaps gained an internet presence in 2015 (Find a Grave 2021).

Published sources
There were many contemporary references to Croll's research within influential books. Thus, there is the first volume of the tenth edition of Principles of geology (Lyell 1867); the fifth edition of Origin of species ; and the first edition of The Great Ice Age by James Geikie (1874). A later book was more equivocal as to Croll's contributions (Ball 1891), and various debates that related to Croll's work are to be found in the letters pages of Nature and elsewhere (e.g., Carpenter  Soon after his death, other than obituaries (e.g., A. G. 1890; Anon. 1890; J. G. 1890; Thomson 1891; Horne 1892), there were accounts which followed the Autobiographical sketch and Memoir (e.g., Alexander 1900;Dryerre 1903), or many decades later and up to the present, hybrid biographical and research accounts of Croll in which the information on his life is clearly based upon Irons's volume (Deacon 1971;Imbrie & Imbrie 1979;Farrow 2001;Gribbin & Gribbin 2001;Bryson 2004).

Concluding point
Popular awareness of Croll is practically non-existent, while his scientific contributions are scarcely recognised by modern-day specialists other than historically aware climatologists and Quaternary scientists. It should be readily apparent from the sources presented here that the range and quantity of material which can inform the life, and particularly the work, of James Croll is considerable. The exploration of this corpus, along with the perspectives offered in this volume, have the potential to provide the bases for a sound, even innovative appraisal of a remarkable man.

Manuscript sources publicly available
These represent all sources known to the writer. More are likely to come to light. The descriptions associated with these items are derived mainly from archival or online sources. The absence of dates, place of writing or further description may be an indication of restricted access. The reference notation for individual items is that used by the holding institutionfor example, 'f.' and 'ff.' or 'folio(s)'; the terms have not been standardised.

The Alfred Russel Wallace page.
This website (Smith 2021) enables a search of connections such as letters, reviews and comments between Wallace and James Croll. It includes copies of the letters that are transcribed in Irons (1896 LD-8-899-P188, P189.JPG. 7 May 1885, 28 Jermyn Street, London SW. Croll's anxiety over money, Geikie will help with Royal Society and the RLF, Geikie's childrens' ailments. Ventnor. (Following letter, same image, to Sir Joseph Hooker sent same day and refers to Croll trying to 'get as much money together as will enable him purchase an annuity of £40 or £50 and that he has been to some extent successful.') LD-8-899-P224, P225, P226.JPG. 28 May 1885, 28 Jermyn Street, London SW. As a steward of the RLF, Geikie was able to plead successfully for Croll. The Royal Society has cancelled your annual subscription and application made to its Scientific Relief Fund. Sir Joseph Hooker has acted 'very chivalrously on your behalf'. Huxley.
LD A formal letter in two hands stating that James Croll is qualified for the post of Geologist with the Geological Survey of Scotland and that the examination should be dispensed with. CSC 11/73,pp. 010,011,012,013. 22 March 1897, 1 Park Row, Albert Gate. Letter to 'Lockhart' with envelope addressed to the Secretary of the Civil Service Commission, Cannon Row, Westminster, and with a copy letter reply (sent 24 March 1897) to 'Mr Porte[r]' at the end. The letter from Porter asked if it is true that the Civil Service 'plucked' [=failed/rejected] Croll 'of "glacial era" fame', as asserted in an issue of The Academy on the authority of his biographer. If this were to be false, as Porter supposed, then he wondered if it should be contradicted. Lockhart responded that he had indeed failed, but that four years later, Clause 7 having been invented, a certificate was issued for him, noting his 'European reputation'. Therefore, 'nothing can be said to The Academy'.
CSC 11/73, p. 014. 28 July 1867. File folder with 'Not to be destroyed' label and stamp. 'Certificate refused' written at top with subjects failed stateduse of instruments, arithmetic, spelling, handwritingalong with a querying '? Over age'. Croll's alternative surnames of Croyle and Croil are also recorded.
CSC 11  MMSID: 9922988743804341. An annotated copy of Croll's paper 'On the probable origin and age of the sun' (Croll 1877) from the collection of James Francis Campbell. The head of the front wrapper is inscribed 'From the Author'; part of an envelope addressed to Campbell is affixed to the back wrapper. Marginalia in Campbell's hand. Tipped in at the start is a letter to Campbell from Croll (dated 9 November 1877) apologising for having missed Campbell when he called into the Edinburgh office.
MMSID: 9922989113804341. An annotated copy of Croll's paper 'Cataclysmic theories of geological climate' (Croll 1878f) from the collection of James Francis Campbell. Marginalia written by Campbell throughout. 9.1.10. National Records of Scotland, 1890-1913 Irons (1896, pp. 120-122) and concerns, inter alia, the paper by Croll (1864e)  NLB/14/161. 14 January 1897. Copy letter from Robert William Frederick Harrison to George Carey Foster enclosing a cheque for £100 voted by the Scientific Relief Committee in aid of James Croll (this is in addition to the sum recorded for 15 January 1891, and further to the funds indicated in Table 2 of Edwards & Robinson (2021) which was published in August 1863, pointing out the correspondence between geological climate and change in the earth's orbit.
Coll-203/1 folio(s) 585. 18 May 1865. Refers to works by Duperry, Nichol and A. Keitz Johnston and discusses superior and subordinate maxima. Asks Lyell to pass on any information he receives from the Astronomer Royal.
Coll-203/1 folio(s) 586-587. 6 November 1865. The temperature of Iceland in the glacial epoch and at the time this letter was written, and how it is affected by season, position of the island and the presence of the Gulf Stream.
Coll-203/1 folio(s) 588-589. 25 December 1865. The eccentricity of the earth's orbit, which Croll has calculated for a million years past, and to come, at 5000 year intervals. He states that his results are favourable to the cosmical theory and will be published in the Philosophical Magazine (Croll 1866a).
Coll-203/1 folio(s) 590-592. 4 January 1866. The build-up of ice during the glacial epoch, the level of the ocean, and his belief that the level of the ocean would not be lowered by the accumulation of ice, as the level of the water would adjust itself to the altered centre of gravity of the earth.
Coll-203/1 folio(s) 593-594. 6 January 1866. Modifications Croll has made to his submergence theory, which held that the level of the ocean would not be lowered by the accumulation of ice, arising from Lyell passing on some calculations as to the amount of water needed from the oceans to form an ice sheet of sufficient mass to alter the earth's centre of gravity. He encloses a letter to The Reader (Croll 1866b), putting the matter straight and asks for Lyell's approval.
Coll-203/1 folio(s) 595. 8 January 1866. Another alteration to his submergence theory, involving the structure of ice caps that have a solid crust covering and a liquid nucleus, which he asks Lyell to send to The Reader (Croll 1866c) with his earlier letter.
Coll-203/1 folio(s) 596-598. 12 January 1866. The rigidity of the earth's crust and the submergence theory, enclosing a copy of his article on the excentricity of the earth's orbit (Croll 1866a Coll-203/1 folio(s) 611-612. 17 April 1866. The quantity of heat received from the sun between two equinoxes, the effect of Perihelion and Aphelion on the length and strength of summers and winters and the effect of the formation of ice and snow on the levels of heat given off from the earth.
Coll-203/1 folio(s) 613-614. 24 April 1866. The temperature of space in relation to the position of the earth and the sun, and different methods of calculating the rate at which the temperature decreases and increases depending on the amount of heat received from the sun.
Coll-203/1 folio(s) 615-618. 23 April 1866. The temperature of the earth in both winter and summer and how this is affected by the position of the earth in relation to the sun, snow and ice.
Coll-203/1 folio(s) 619. 29 June 1866. Telling Lyell that he does not have anything ready to print in the July issue of the Philosophical Magazine.
Coll-203/1 folio(s) 620-621. 6 July 1866. Calculations of the thickness of the ice sheets and the extent of the submergence, the effect on the climate of the ice sheet, and his belief that the grinding down of rock cannot be attributed to floating ice but to the extent of time that the rock was covered in ice. He feels confident that the submergence and emergence both of the glacial and coal periods can be accounted for on cosmical principles.

Rare Book and Manuscript Library
Three period copies of letters dated 28 March, 1 April, 6 April 1884, sent by Joseph Dalton Hooker to James Croll and copied onto blind-stamped paper bearing the address of Montreal Cottage, Perth. This was the address of Croll's friend Dr John Bower, a retired fleet-surgeon and the copyist. The letters are transcribed in Irons (1896, pp. 423-28) from originals sent from Kew by Hooker. They discuss issues of Arctic interest including the 'hopelessly unintelligible' question of whether specimens of wood found in the Arctic are evidence of interglacial warming periods, expressing scepticism as to Sir Edward Belcher's claims to have found a tree stump embedded in frozen clay. MS.7777/8. A letter from John Tyndall to James Croll held at the Wellcome Library. Tyndall mentions negative fluorescence (calorescence), mechanics, molecules and motion. He asks if Croll wishes his note to be sent to the Philosophical Magazine. This is a reply to a letter from Croll to Tyndall held at the Royal Institution (RI MS JT/TYP/1/65-66).

Manuscript sources for sale or in private hands
The items below should be read in combination with the details discussed in section 5.

Christie's, London.
Letters from Sir Joseph Dalton Hooker to James Croll, 1883Croll, -1884 Christies's auction house had two related sales of Croll-related material on 17 September 1999 (Lot 163; estimate £150-£250, price realised £55) and 9 October 2012 (Lot 83; estimate £1000-£1500, price realised £125). The first consisted of five autograph letters from Hooker, Kew Gardens, to James Croll on Arctic and Antarctic topics, with comments on Sir Edward Belcher: 'Belcher you know was a notoriously untruthful man…the best (and most deservedly) hated man of his day in the Navy'. They consisted of 23 pages and were dated 25 November 1883-6 April 1884. A letter of 6 April 1884 lacked the second bifolium and another dated 23 December 1883 is also recorded, while the sale was accompanied by a photograph from a letter dated 28 March 1884. They were sold together with contemporary copies (including a complete text of the letter of 6 April 1884). Quotations from the letters, along with the photograph, indicate these to include those transcribed in Irons (1896), viz. 25 November 1883 (Irons 1896, pp. 407-10), 23 December 1883 (Irons 1896, pp. 418-19) and 28 March 1884 (Irons 1896, pp. 423-24). The contemporary letters almost certainly refer to those of 28 March, 1 April, 6 April 1884, sent by Hooker to Croll and copied onto blind-stamped paper bearing the address of Montreal Cottage, Perth (see under University of Illinois, section 9.1.20).
The 9 October 2012 (Lot 83) sale would seem to be the same material as for the 17 September 1999 sale, with the addition of a signed portrait of Hooker. It seems that the three copy letters on Montreal Cottage notepaper were acquired by the Wayfarer's Bookshop, British Columbia, Canada, whence they made their way to the University of Illinois in 2015.
Presentation copy of Alfred Russell Wallace volume to James Croll with notes, 1880 A first edition presentation copy to James Croll of Island life (Wallace 1880) sold as Lot 408 on 11 September 1992 by Christie's in London (price realised £55). The book contained a tipped-in slip inscribed 'From the Author', and extensive notes in the margins of chapters VII-X. The manuscript notes were possibly used by Croll in the revision of his own work (presumably Croll 1885b).

Croll's paper on ocean currents, 1874.
An offprint of Croll's (1874a) paper and signed 'With the author's compliments' was available on the eBay platform in July 2021 and offered for sale by Robin Rare Books Division of the Midtown Scholar Bookstore, Harrisburg, Pennsylvania. The word 'Edinburgh' is also added beneath the printed address of the article's title page.

Bound papers, 1855-1874.
A collection of 41 offprints sent to Croll and on sale at the time of writing by Jeff Weber Rare Books, Montreux. The listed contents at the start of the bound volume are not in the hand of Croll (Jeff Weber, pers. comm. April 2021).

Disbound papers, 1865-1885.
A website detailing 19 items 'from the library of James Croll' is currently available from John Turton Antiquarian Books of Crook, Co. Durham (Turton 2021). This part of a collection of offprints bought by Turton's around the year 1990 from the Hodgson's Rooms division of Sotheby's (Ben Bainbridge, pers. comm. April 2020; cf. sections 5, 9.2.3. and 9.2.5.). 9.2.5. Material currently in the possession of Kevin J. Edwards.

Offprints, 1870-1879
A collection of five offprints (Croll 1870b(Croll , 1875c(Croll , d, e, 1879c, sent to Joseph Henry (1797-1878), Director of the Smithsonian Institute and obtained from Ed Rogers Rare and Out of Print Geology Book, Poncha Springs, Colorado. One of them (Croll 1875c) is inscribed 'To Professor Henry with the author's compliments' and is in the hand of Croll. Another with the words 'With the Author's compliments' (Croll 1879c) is not. The sale came with an advertising leaflet for Climate and time with the words 'D. Appleton of New York', in Croll's hand, written beneath the printed details of the British publishers (section 5). In addition, there is an offprint (Woodward 1873) sent to Croll and bearing the inscription 'J. Croll Esq re '. Henry Bolingbroke Woodward (1832Woodward ( -1921 was keeper of geology at the British Museum and a signatory to Croll's nomination for the Royal Society of London (Edwards 2021). This is probably not in the hand of Croll. The offprint came from Croll's collection and was obtained from John Turton Antiquarian Books of Crook, Co. Durham.

Copies of Climate and time, 1875
The copy of Climate and time (Croll 1875a) sent to Charles Wyville Thomson of the Challenger expedition, inscribed 'To Professor Wyville Thomson LL.D., FRSfrom the Author' (see section 5; Fig. 3) and acknowledged by Thomson from Ascension Island on 2 April 1876 (section 9.1.3, ff. 86, 87;Irons 1896, pp. 308-09). The book subsequently passed into the library of Thomson colleague, John Murray, and bears his bookplate. A second copy contains the inscription 'With the author's kind regards', and its owner came from Alford, Aberdeenshire, Scotland.

Bound papers, 1879-1880
A collection of papers sent to Croll and comprising 25 offprints with 'Pamphlets -Foreign -Vol. III' in gold lettering on the spine (section 5). The papers are listed by author, and either journal or summary article title, at the start of the volume in a hand which is not that of Croll. The volume would appear to be a companion to that described in section 9.2.3.

Copies of Autobiographical sketch of James Croll, 1896
One copy of James Campbell Irons (1896) contains an inscription to a Mr James G. Lunn of Paisley, with two items pasted into the front pages concerning Croll as a scientist and the location of his grave. A second copy is inscribed by Irons to the Dominican preacher, Father Arthur Henry Bertrand Wilberforce, grandson of politician and slavery abolitionist William Wilberforce (Fig. 4). More information on both volumes may be found in section 5.