Hooker, Sir Joseph Dalton
- Jim Endersby
Sir Joseph Dalton Hooker (1817–1911)
Hooker, Sir Joseph Dalton (1817–1911), botanist, was born at Halesworth, Suffolk, on 30 June 1817, the younger son of Sir William Jackson Hooker (1785–1865), regius professor of botany at Glasgow University, and his wife, Maria Sarah (1797–1872), daughter of Dawson Turner. Hooker attended his father's university botany lectures from the age of seven and formed an interest in plant distribution. Another early enthusiasm was travellers' tales—he recalled sitting on his grandfather's knee looking at the pictures in Captain Cook's Voyages. He was particularly struck by one showing Cook's sailors killing penguins on Kerguelen's Land, and he remembered thinking that, 'I should be the happiest boy alive if ever I would see that wonderful arched rock, and knock penguins on the head' (Huxley, 6). He was educated at Glasgow grammar school and at Glasgow University, where he graduated MD in 1839.
The Erebus voyage, 1839–1843
Hooker's passions for botany and travel were combined when he was appointed assistant surgeon aboard HMS Erebus, which—commanded by James Clark Ross and accompanied by its sister ship, the Terror—was to spend four years exploring the southern oceans. The ships wintered in New Zealand and Van Diemen's Land (Tasmania), and also visited the numerous tiny islands around Antarctica. These included Kerguelen's Land, where Hooker was finally able to gratify his desire to knock penguins on the head. More important, the sojourns ashore allowed him to collect plants in relatively unexplored regions. Before Hooker set sail Charles Lyell of Kinnordy (father of the geologist) had given him the proofs of Charles Darwin's Voyage of the Beagle, which he read eagerly, excited but a little overwhelmed at the 'variety of acquirements, mental and physical, required in a naturalist who should follow in Darwin's footsteps' (F. Darwin, 19–20). Hooker was not alone in seeing Darwin as a role model: Ross wanted 'such a person as Mr. Darwin' as the expedition's naturalist, but felt that Hooker had not yet proved himself of Darwin's calibre. After Ross appointed him to the inferior position of expedition's botanist Hooker complained to his father 'what was Mr. D. before he went out? he, I daresay, knew his subject better than I now do, but did the world know him? the voyage with FitzRoy was the making of him (as I hoped this exped. would me)' (Huxley, 41).
Travel was a major way in which aspiring men of science like Hooker and Darwin could gain themselves a reputation. Although Ross was a friend of William Hooker and encouraged Joseph's botanical work during the voyage, William's income would not allow Joseph to travel as a self-financed, gentlemanly companion to the captain—as Darwin had done. Instead Joseph sailed as a lowly assistant surgeon, subject to naval discipline and with many shipboard duties to perform.
When the Erebus returned to England in 1843 Hooker needed to find paid botanical employment. Two years earlier his father had been appointed first director of the Royal Botanic Gardens at Kew, which had just been brought under government control. The appointment brought William Hooker to the centres of scientific life in London but reduced his income and he was still unable to give his son much financial support. Fortunately his influence was sufficient to secure an Admiralty grant of £1000 to cover the cost of the Botany of the Antarctic Voyage's plates, and Joseph received his assistant surgeon's pay while he worked on it. The book eventually formed six large volumes: two each for the Flora Antarctica, 1844–7; the Flora Novae-Zelandiae, 1851–3; and the Flora Tasmaniae, 1853–9. None the less Hooker's Antarctic publications never made any money, and much of his time in the 1840s was taken up with searching for paid employment. In 1845 he was an unsuccessful candidate for the chair of botany at the University of Edinburgh. His father's contacts helped him secure work at the geological survey from 1846 to 1847, but he still had no permanent position.
Friendship with Darwin
Shortly after his return from the Antarctic, Hooker received a letter from Darwin congratulating him on his achievements, offering specimens from Tierra del Fuego, and asking whether Hooker would be interested in classifying the plants Darwin had gathered in the Galápagos. At this time the two men hardly knew each other, having met only once, shortly before Hooker set sail. Nevertheless Hooker was flattered by his scientific hero's attention and began the Galápagos work. These first letters marked the beginning of a lifelong correspondence, through which the two became friends and collaborators, and debated their many scientific interests—notably over questions of plant distribution. The rapid deepening of their friendship is evident from a letter Darwin wrote on 14 January 1844: 'I am almost convinced', he told his new acquaintance '(quite contrary to opinion I started with) that species are not (it is like confessing a murder) immutable', adding 'I think I have found out (here's presumption!) the simple way by which species become exquisitely adapted to various ends' (Correspondence, 3.2). The 'simple way' was, of course, natural selection, and Hooker was the first in the world to hear of Darwin's secret. In the early nineteenth century, the origins and nature of species, including humans, were two of the most contentious topics naturalists faced. So, despite his tongue-in-cheek description of himself as confessing a murder, Darwin genuinely feared that Hooker might be appalled by his ideas; he must have been relieved when Hooker replied that there might well have been 'a gradual change of species,' adding, 'I shall be delighted to hear how you think that this change may have taken place, as no presently conceived opinions satisfy me on the subject' (Correspondence, 3.6–7).
Hooker's calm reply was probably shaped by some degree of deference, but also suggests a pre-existing interest in the species question. Although Hooker said little about his own opinions until the late 1850s his willingness to listen to Darwin's ideas opened the way to a long and fruitful correspondence. As Darwin worked out the details of his theory over the next fourteen years the two men regularly discussed natural selection and Darwin would later acknowledge Hooker as 'the one living soul from whom I have constantly received sympathy' (Correspondence, 7.174). Yet Hooker never hesitated to criticize Darwin when he disagreed with him. Writing to Lyell in 1866 Darwin noted that Hooker's 'mind is so acute and critical that I always expect to hear a torrent of objections to anything proposed; but he is so candid that he often comes round in a year or two' (More Letters, 138).
The geographical distribution of plants was a central concern for Hooker. He was puzzled, for example, by the species he had seen growing on widely scattered islands; like other naturalists he wondered how they had got there. One option was simply to assume that God had created them several times in their existing locations, but Hooker rejected this theory of multiple centres of creation, and sought a more law-like explanation. He assumed that each species had been created (by an unknown means) at a single time and place from where it had spread. However, this did not explain how species travelled over huge expanses of ocean. Hooker's solution drew on the work of his friend and colleague, Edward Forbes, Britain's most vociferous proponent of single centres of creation. Forbes argued that the plants had migrated at a time when the isolated islands had been connected, but that sea levels had since risen—as proposed by Lyell's geological theories—leaving disconnected lands with common floras. Hooker explained the distributional puzzles of the Southern Ocean by hypothesizing that a much larger Antarctic continent had once linked many of the now isolated lands. Darwin proposed instead that anomalous distributions were better explained by seeds having been carried by birds and animals, or wind and ocean currents. He and Hooker argued over their competing theories for many years.
Studying plant distribution promised to shed light on the origins of species, but also had more practical implications. The wealth of Britain's empire was largely based on plants: from cotton and timber, spices, indigo and other dyes, to the gutta-percha (natural latex) so essential to Britain's dominance of cable telegraphy. Voyages like Hooker's were partly concerned with mapping these vital natural resources and discovering new ones. But it was also hoped that such mapping would eventually reveal the laws that explained why particular plants grew where they did. Such laws would aid the search for new plants, and make transplanting crops between colonies much easier. However, plant distribution studies required a global survey of vegetation and even after his voyage Hooker needed many more specimens before he could write his floras. Unfortunately the government's funding of Kew during the middle decades of the century did not include provision for professional collectors, and neither William nor Joseph Hooker could afford to pay them out of their own pockets. Instead they had to rely on a diverse group of unpaid enthusiasts who eventually supplied the tens of thousands of specimens that allowed Joseph to complete his books while building his herbarium and reputation.
The imperial context and importance of Hooker's work is also evident in his trip to the central and eastern Himalaya (1847–9). Hooker obtained a government grant for the trip and the Admiralty gave him free passage on the ships taking Lord Dalhousie, the newly appointed governor-general, to India. After visiting Calcutta, Hooker went to Darjeeling, where he met Brian Houghton Hodgson who was an expert on Nepalese culture and Buddhism, a collector of Sanskrit manuscripts, and also a passionate naturalist. The two became close friends and Hodgson helped Hooker prepare for his trip into the Himalaya. However, by the time Hooker was ready to set off for Sikkim in 1848 Hodgson was too ill to accompany him and Dr Archibald Campbell, the British government agent, went instead.
Sikkim—a small and impoverished state—was bordered by Tibet, Nepal, and Bhutan, as well as British India. Its raja was understandably anxious not to annoy any of his powerful neighbours, so he and his chief minister, the diwan, were particularly suspicious of travellers like Hooker who surveyed and made maps during their travels. (Their suspicions proved well founded, as Hooker's maps later proved to have both economic and military importance to the British.) When Hooker first sought permission to enter Sikkim the diwan made considerable efforts to prevent him, and even after pressure from the British administration forced the diwan to submit he obstructed their progress in various ways. He particularly urged them not to cross the northern border with Tibet during their explorations, but Hooker and Campbell knowingly ignored his order and the border violation was used by the diwan as a pretext to arrest and imprison them in November 1849. The British government secured their release within weeks by threatening to invade Sikkim. The elderly raja was punished with the annexation of some of his land and the withdrawal of his British pension, a response that even some of the British thought excessive.
Following his release Hooker spent 1850 travelling with his old university friend Thomas Thomson in eastern Bengal and the two returned to England in 1851. Together they wrote the first volume of a projected Flora Indica (1855), which was never completed because of a lack of support from the East India Company. However, the introductory essay on the geographical relations of India's flora was to be one of Hooker's most important statements on biogeographical issues.
Altogether Hooker collected about 7000 species in India and Nepal and on his return to England managed to secure another government grant while he classified and named them. The first publication was the Rhododendrons of the Sikkim-Himalaya (1849–51), edited by his father and illustrated by Walter Hood Fitch, whose fine drawings enriched many of both the Hookers' publications. Hooker's and Campbell's travels added twenty-five new rhododendrons to the fifty already known and the spectacular new species they introduced into Britain helped create a rhododendron craze among British gardeners. Hooker's journey also produced his Himalayan Journals (1854), which were dedicated to Darwin.
The consolidation of a career
On 15 July 1851 Hooker married Frances Harriet (1825–1874), eldest daughter of John Stevens Henslow, the Cambridge professor of botany who had taught Darwin. Joseph and Frances had four sons and two surviving daughters, but Hooker's favourite daughter, Minnie (Maria Elizabeth), died in September 1863 when she was just six years old. He wrote to Darwin (who had suffered a similar blow a dozen years earlier when his daughter Annie had died) that 'It will be long before I cease to hear her voice in my ears, or feel her little hand stealing into mine; by the fireside and in the garden, wherever I go she is there' (Turrill, 191). Hooker was close to his children and enjoyed playing with them. He also followed Darwin's suggestion and not only attended their births but gave his wife the anaesthetic chloroform during labour, as Darwin had done for Emma—a procedure the two men agreed was as soothing for themselves as for the mother. Frances died in 1874 and on 22 August 1876 Joseph married Hyacinth Jardine (1842–1921), only daughter of William Samuel Symonds, with whom he had two more sons.
The 1850s also saw the appearance of several of Hooker's most important publications. These were largely taxonomic, concerned with classifying and naming new species and with reclassifying previously known ones. Hooker was a taxonomic ‘lumper’, a proponent of large, broadly defined species that encompassed many varieties that others classified as separate species. Hooker's lumping was undoubtedly a product of his global plant surveys—compiling these imperial inventories was made nightmarishly complex by those he called hair-splitters, who gave a new name to every minor variation they spotted, thus multiplying species and names. In an effort to overrule the splitters Hooker claimed that the size of Kew's herbarium (which contained about 150,000 species by the early 1850s) allowed global comparisons that made his judgements superior to those of botanists who only knew the plants of their locality.
The herbarium and gardens at Kew had grown substantially since William Hooker had been put in charge. When the government finally agreed that the director could not cope alone their decision gave Joseph the secure, paid employment he sought: he was appointed assistant director on 5 June 1855.
While Hooker was travelling, publishing, and making his name, Darwin was still working in secret on his 'big species book'; only his close friends knew that he was planning a comprehensive account of his long-held theory. On 15 June 1858 Darwin received a letter from Alfred Russel Wallace, then in the Celebes Islands (Sulawesi), in which Wallace asked for Darwin's help in publishing his own theory of the transmutation of species—a theory that largely anticipated Darwin's own. Darwin was anxious not to lose priority for his idea, but was equally concerned not to treat Wallace unjustly. As he and several of his children were ill he left Hooker and Lyell to decide what to do. They arranged for Wallace's paper to be read at a meeting of the Linnean Society on 1 July, but to be accompanied by an abstract of Darwin's theory (which Hooker had read in 1844) and by a letter to Asa Gray, the American botanist, which substantiated Darwin's claim to priority. After the meeting Hooker wrote to Gray that he was 'Most thankful … that I can now use Darwin's doctrines—hitherto they have been kept secrets I was bound in honor to know, to keep, to discuss with him in private—but never to allude to in public' (Porter, 32–3).
Although the Linnean Society paper did not create much public interest Wallace's letter persuaded Darwin to publish a shortened, more accessible version of his theory immediately, and the Origin of Species appeared in November 1859. A month later Hooker published his 'Introductory essay on the flora of Tasmania' (the final part of the Flora Tasmaniae), in which he announced his public support for 'the ingenious and original reasonings and theories by Mr. Darwin and Mr. Wallace' (Hooker, 3.ii). As evidence for natural selection Hooker offered a detailed analysis of the distribution of the Australian flora, arguing that a combination of his earlier Forbesian geological theories and Darwin's could best explain the observed distribution of plants.
Kew under Hooker
In 1865 Hooker's father died and Joseph succeeded him as director of Kew. Hooker was by this time a highly regarded botanist with a worldwide reputation, though he might not have secured the position without his father's constant assistance: William Hooker had offered to leave his vast private herbarium to the nation as long as Joseph was appointed to succeed him. Hooker remained director of Kew until his retirement in 1885. These twenty years were marked by the continuation and expansion of Kew's imperial role. In 1859–60 William Hooker and Kew had provided essential assistance in the transfer of Cinchona (the tree from whose bark quinine was made) from South America to India. This enabled this crucial crop to be grown in a British colony with plentiful supplies of cheap labour, resulting in cheaper, more reliable supplies of a drug essential to combat the malaria endemic to many tropical colonies. The cinchona transplantation was emulated under Joseph Hooker's direction in the 1870s when rubber trees (Hevea brasilensis) were removed (entirely without the knowledge or permission of the Portuguese government of Brazil) to be grown in British colonies, especially in Ceylon (Sri Lanka), Singapore, and Malaya.
The public function of Kew became a source of controversy in various ways during Hooker's tenure as director. He asserted that the garden's 'primary objects are scientific and utilitarian, not recreational' and complained about the need to create elaborate floral displays for those he regarded as 'mere pleasure or recreation seekers … whose motives are rude romping and games' (Desmond, Kew, 230, 234). Given these views it is hardly surprising that he continued the tradition of allowing only serious botanical students and artists to enter the gardens during the morning, and resisted all attempts to extend the garden's opening hours for the general public.
Behind this opposition to admitting the public and providing better facilities for them lay an anxiety about the scientific standing of Kew and of botany more generally. Botany continued to enjoy enormous popularity with non-professionals and was associated in the public mind with respectable middle-class activities, such as gardening and flower painting. It was also particularly popular with women—at a time when the world of Victorian science was almost entirely dominated by men. Hooker's long struggle to find a paid botanical appointment may have made him peculiarly sensitive to issues about the status of his studies. His concern to transform botany into a properly ‘philosophical’ study, one concerned with the laws of distribution and the origin of species, helps explain his opposition to the pleasure seekers and 'rude rompers'.
In the 1870s anxieties over the status of Kew—and over his personal standing in the scientific world—drew Hooker into conflict with Acton Smee Ayrton, the first commissioner of the Office of Works (which had taken over control of Kew from the Office of Woods and Forests in 1850). Hooker's notorious irritability—even Darwin described him as 'impulsive and somewhat peppery in temper' (Autobiography, 105)—probably contributed to the conflict, but the immediate focus of what became known as the Ayrton controversy was Richard Owen's natural history museum at South Kensington. The new building was to house the natural history collections of the British Museum, including the vast herbarium of Sir Joseph Banks. In 1868 Hooker had proposed that the Banksian herbarium be transferred to Kew, citing mismanagement at the British Museum as his justification. Owen, then keeper of the British Museum's natural history collections, opposed Hooker's plan, which would have jeopardized his new museum. Sharp ideological differences lay behind the dispute: Hooker was one of Darwin's best-known public defenders, while Owen was a vociferous opponent.
By 1872 Ayrton had already made several attempts to cut public spending on scientific institutions and had clashed with Hooker several times as he tried to assert his authority over Kew. He now privately consulted Owen on the future of the rival herbaria and Owen, not surprisingly, proposed that Kew's collections be transferred to the natural history museum—a proposal that would have reduced Kew to a mere public park. Hooker resisted this strongly, calling in every prominent British man of science he knew, including Darwin and Lyell, to protest publicly against the proposed change. After debates in both houses of parliament Hooker and the Darwinians succeeded in getting Ayrton transferred to the office of judge advocate-general. Both Kew and the British Museum (Natural History) retained their respective collections, and at the general election of 1874 Ayrton lost his seat.
Yet despite Hooker's autocratic opposition to anything he regarded as diluting Kew's scientific role he did not oppose widening public participation in science. In 1866 he addressed the British Association for the Advancement of Science (BAAS), whose meetings the general public were encouraged to attend, and delivered a lecture, 'Insular floras', in which he finally gave up what he now called 'sinking imaginary continents' and instead adopted Darwin's theory of plant distribution by migration. Hooker's involvement with the BAAS also included presiding over the department of zoology and botany in 1874 and over the geographical section in 1881. In 1873 Hooker was elected president of the Royal Society, where he instituted various reforms designed to broaden public participation in the society, including the ladies' soirées. When he retired from the presidency in 1878 Hooker was particularly proud of the £10,000 he had helped raise which allowed the restrictively high membership dues to be reduced.
In public Hooker was extremely reticent about his political and religious views. However, in a letter to Gray he described himself as a whig and elsewhere referred to himself as 'a philosophic conservative, a strong Unionist, but not a Tory' (Turrill, 197). However, he never expressed much interest in party politics and was similarly discreet about his religious views. He refused to give public support to Sir John Lubbock's petition in support of the authors of the Essays and Reviews (a collection of essays by liberal clergymen that questioned traditional readings of scripture) because he claimed to be unsure about the benefits of Lubbock's campaign. He was similarly cautious in the controversy over the work of John William Colenso, the bishop of Natal, whose doubts about the historical accuracy of parts of the Old Testament led to his excommunication in 1863. Hooker gave money to Colenso's defence fund provided that his name was not published; he told Darwin he was anxious to avoid upsetting his devout, traditionalist mother. In private Hooker's religious views were close to the agnosticism of his friend Thomas Henry Huxley; in a letter to his friend, the clergyman and amateur naturalist James Digues de la Touche, Hooker expressed praise for Huxley's concept of 'a religion of pure reason' (Turrill, 198). Huxley and Hooker were among the founders of the X Club, a private dining society that supported Darwinism and opposed those they saw as obstructing scientific progress, especially traditional churchmen. In letters to Huxley, Hooker was forthright about his dislike of theological dogmatism, sacerdotalism, and ceremony, but nevertheless remained a churchgoing Anglican and agreed to act as godfather for Huxley's son.
Hooker's place in history
According to his son-in-law William Thiselton-Dyer, Hooker was 'five feet eleven inches in height and spare and wiry in figure' (there are portraits of him at the Royal and Linnean societies and numerous photographs and drawings at Kew) and 'in temperament he was nervous and high-strung'. Thiselton-Dyer also attested to Hooker's capacity for hard work, a claim borne out by the full list of his publications, which fills twenty pages (Huxley, 486–506). Some of the more important later ones include: 'Outlines of the distribution of Arctic plants' (1862); the Student's Flora of the British Isles (1870); Genera plantarum (with George Bentham, 1860–83); the Flora of British India (1855–97); editing the Journal of Joseph Banks (1896); completing Trimen's Handbook of the Flora of Ceylon (1898–1900); and, finally, writing a sketch of the life and labours of his father (1902). As well as writing he continued to travel and visited Syria (1860), Morocco (1871), and the Rocky Mountains of Colorado and Utah (1877).
Hooker was highly regarded in his lifetime and received numerous honorary degrees including ones from Oxford and Cambridge. He was created CB in 1869; KCSI in 1877; GCSI in 1897; and received the OM in 1907. The Royal Society gave him their royal medal in 1854, the Copley in 1887, and the Darwin in 1892. He received numerous prizes and awards from both British and foreign scientific societies; the full list of his honours runs to ten pages (Huxley, 507–17).
Although botanists have long recognized Hooker's taxonomic skills and his pioneering work on distribution, his wider reputation has been somewhat obscured by his close relationship with Darwin. When Hooker appears in histories of nineteenth century science, it is almost invariably as a minor character in Darwin's story and his own work, attitudes, and opinions have been neglected as a result. However, recent scholarship has begun to recognize that Hooker's preoccupations—especially taxonomy, botanical distribution, and the disciplinary status of botany—are central to understanding the material practices of nineteenth-century natural history, particularly in its imperial context. Hooker's correspondence with his colonial collectors illustrates how the practices of nineteenth century natural history need to be seen as a complex series of negotiations, rather than in terms of straightforward metropolitan dominance; much existing historiography has assumed that those in the colonies were passive servants of imperial science, and as a result their interests and careers have been neglected. Hooker's career also casts doubt over standard accounts of the professionalization of British science, particularly over the assumption that he and the other young professionalizers (especially those in the X Club) were determined to replace institutions based on patronage with those based on merit: Hooker inherited Kew from his father and bequeathed it to his son-in-law—and the role of patronage in these transitions is unmistakable. Likewise, Hooker's equivocation over Darwinism undermines the assumption that it functioned as a unifying ideology for the professionalizers. While he welcomed and embraced natural selection as allowing naturalists to form 'more philosophical conceptions', he also stressed that both Darwinists and non-Darwinians 'must employ the same methods of investigation and follow the same principles' (Hooker, Flora Tasmaniae, iv). This apparent ambivalence probably resulted from his need to maintain good relations with his diverse collecting networks, whose members were often deeply divided over the species question. As is illustrated by the Ayrton controversy, conflicts over Darwinism were potentially dangerous to a man in Hooker's position.
Hooker died in his sleep at midnight at his home, The Camp, Sunningdale, on 10 December 1911 after a short and apparently minor illness. His widow, Hyacinth, was offered the option of having him buried alongside Darwin in Westminster Abbey but perhaps she understood that—despite the importance of his relationship with Darwin—it was botany, Kew Gardens, and his father which should determine his final resting place; Hooker was buried, as he wished to be, alongside his father in the churchyard of St Anne's on Kew Green on 17 December.
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- RBG Kew, corresp. with Thomas Anderson
- RBG Kew, letters to W. E. Darwin
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- RGS, letters to John Hogg
- RGS, letters to Royal Geographical Society
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- T. H. Maguire, lithograph, 1851, BM, NPG; repro. in T. H. Maguire, Portraits of the honorary members of the Ipswich Museum (1852)
- W. E. Kilburn, daguerreotype, 1852, NPG
- W. Walker, mezzotint, pubd 1854 (after F. Stone), BL OIOC
- Maull & Polyblank, albumen print, 1855, NPG
- G. Richmond, oils, 1855, priv. coll.
- J. M. Cameron, photograph, 1868, National Museum of Photography, Film and Television, Bradford, Royal Photographic Society collection [see illus.]
- J. Collier, oils, 1880, RS
- H. von Herkomer, oils, 1889, Linn. Soc.
- F. Bowcher, silvered copper medal, 1897, NPG
- F. Bowcher, Wedgwood medallion, 1897, NPG
- W. Rothenstein, lithograph, 1903, NPG
- W. Rothenstein, pencil drawing, 1903, NPG
- F. G. M. Gleichen, drawing, 1908, Royal Collection
- E. Cook, oils, 1909, RBG Kew
- E. Edwards, photograph, NPG; repro. in L. Reeve, ed., Portraits of men of eminence, 2 (1864)
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- C. H. Jeens, stipple, BM, NPG
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- H. J. Whitlock, carte-de-visite, NPG
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- photogravure (aged eighty), BM
Wealth at Death
£36,861 5s. 1d.: probate, 1912, CGPLA Eng. & Wales