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Meldola, Raphael


(b. London, England, 19 July 1849; d. London, 16 November 1915)

chemistry, biology, science administration.

Raphael Meldola was the son of Samuel Meldola and grandson of Raphael Meldola, the chief rabbi of London during the first half of the nineteenth century. Of sephardic lineage, the family traced its ancestry back through sixteen generations to Toledo in the late thirteenth century. According to family tradition, the Meldola surname was derived from a town near Ravenna, Italy.

Meldola’s early education took place at Gloucester House School in Kew, which in the early 1860’s was still a rural village on the outskirts of London, and at a boarding school kept by a relative, Rev. A. P. Mendes, at Northwick College. Maida Vale. In 1866 Meldola entered the Royal College of Chemistry, where for a while he ws an assistant in the laboratory of John Stenhouse. Despite his deep interest in natural history. Meldola earned his living as a chemist. In 1868 he became chemical adviser to W. & W. H. Stead, Seed Crushers and Oil Refiners, of Liverpool, For more than two years, beginning in 1870. Meldola tried his hand full-time in industrial chemistry at Williams. Thomas and Dower, color manufacturers, at the Star Chemical Works in Brentford. The position offered him limited scope for his own research interests, so in 1873 Meldola returned to the Royal College of Chemistry at its new home in South Kensington to work as a private assistant in Edward Frankland’s laboratory. In 1874 Meldola joined Joseph Norman Lockyer’s laboratory for a three-year period, during which he studies problems relating to spectral analysis and the chemistry of photography. As Lockyer’s assistant he took charge of the Royal Society eclipse expedition to Camorta in the Nicobar Islands when his chief was unable to go. The eclipse occurred on 6 April 1875, and although clouds prevented the party from observing the brief moment of data for publication.

During this academic interlude Meldola also taught organic chemistry as a lecturer at St. Mark’s College in Chelsea and general science at the Ratcliff School of the Cooper’s Company. In 1877 he again turned to the industrial side of chemistry when he took the position of “scientific chemist” in the laboratory of Brooke, Simpson, and Spiller at the Atlas Colour Works of Hackney Wick. During the ensuing eight years he was given free reign to explore and to publish his research. It was here that Meldola began working on the chemistry of coal tar and initiated the lines of investigation that he developed throughout his career. He returned to an academic setting in 1885 when he joined Finsbury Technical College, an institution sponsored by the City and Guilds of London Institute, to occupy its chair of chemistry. That same year Silvanus P. Thompson, who had been a fellow student at the Royal College of Science during the mid 1870’s became principal of the college and professor of physics. The association rekindled a lifelong friendship. In 1886 Meldola married Ella Frederica Davis. Children are mentioned in various biographical accounts, but not by name.

Meldola was particularly active as a member of the Chemical Society of London. From 1883 to 1886 and again in 1890, he served as a member of its council; in 1901 and 1902 he performed the function of foreign secretary: between 1902 and 1905 he served as vice president; and from 1905 to 1907 he held the office of president. During much of that period Meldola also served the Institute of Chemistry of Great Britain and Ireland. Founded in 1877, this organization was intended to oversee the areas where professional chemists and analysts performed public services. Meldola was vice president of the institute between 1909 and 1912 and its president from 1912 until his death. While president, Meldola particularly advanced the interests of the teachers of chemistry and successfully brought about the move of the institute to new quarters. In 1908 and 1909 he also was president of the Society of Chemical Industry, an institution founded to strengthen the bonds between academic and industrial chemists. In all, he was clearly an effective and respected leader in the management of science. The Chemical Society’s historians best capture these talents by describing Meldola as “a good man of affairs—clear, judicious, tactful, and good-humoured.”1

Throughout his life as a chemist, Meldola remained an ardent enthusiast of natural history. As a young man he was personally encouraged in this avocation by John Keast Lord, author of At Home in the Wilderness (1867). He maintained an eleven-year friendship with Charles Darwin. He corresponded extensively with the great German naturalist Fritz Müller, and he was a good friend of Alfred Russel Wallace. He joined the Entomological Society of London in 1872, served as its secretary between 1876 and 1880, and was president in 1895 and 1896. On the basis of his work in entomology. Meldola was proposed by Darwin for membership in the Royal Society. He was elected a fellow in 1886 and served on its council from 1896 to 1898 and again in 1914 and 1915. In 1914 he was appointed a vice president of the society. In 1880 he became a founding member of the Essex Field Club, an organization devoted to natural history, archaeology, and the preservation of wild areas.

Meldola received many honors for his work in chemistry and natural history. In 1910 Oxford University awarded him an honorary D.Sc.; on that occasion Meldola delivered the Herbert Spencer Lecture. In 1911 he received an LL.D, from St. Andrew’s; in 1913 the Royal Society awarded him the Davy Medal; and both in 1901 and 1913 he received the Albert Medal of the Society of Arts for papers on industrial chemistry. In 1911 the French Chemical Society presented him with its Jubilee Award, and the Italian city of Turin honored him with a gold medal. In 1900 and in 1907 the French government invited Meldola to receive the Legion of Honor, but on both occasions the British Foreign Office forbade him to accept the award.

Meldola died while actively engaged in Britain’s wartime efforts. He had been a founding member and, from 1911 on, president of the Maccabaeans, a London-based society that promoted the affairs of British Jews in the professional world. Meldola was buried on 18 November 1915 in the Spanish-Portuguese (Sephardic) Cemetery at Golder’s Green. He bequeathed his entomological collection and cabinets to the Hope Museum at Oxford. Among his other bequests was the sum of £200 to Sutherland Technical College for awards for swimming and lifesaving, which became known as Meldola badges.

Chemistry. As a result of the enormous success of the coal-gas industry, organic chemistry in the second half of the nineteenth century went through a dramatic revolution. One of the major by-products of the destructive distillation of gas from coal was coal tar, which by the 1850’s chemists, such a August Wilhelm von Hofmann and William Henry Perkin, began to analyze systematically. Meldola concentrated his own research entirely on the chemistry of coal tar and on a limited number of problems closely associated with the production of synthetic dyes. He had no graduate students at Finsbury whom he could set on a range of related projects; he had to rely instead upon a single paid assistant and the cooperation of a line of willing collaborators. The chemist Arthur G. Green wrote in retrospect that “Meldola’s technical researches were in great measure of a pioneer character; they opened up new ground, but were not always capable of bearing immediate fruit.”2 His former collaborator John V. Eyre and Ernest Harry Rodd gave further perspective on Meldola’s chemical career by noting that the Finsbury phase was “. . . not characterized by the earlier originality, but rather by dogged perseverance in selected lines of investigation.”3Nevertheless, his peers and students recognized Meldola as a craftsman who paid meticulous attention to details, who had a vast knowledge of the chemical literature, and who was a dextrous performer at the laboratory bench.

One major line of Meldola’s work, begun in 1878 and the subject of eleven memoirs over a twenty-year period, entailed the discovery and analysis of many derivatives of naphthalene, a product of a fraction of coal tar known as “carbolic oil.” This work helped unravel the complexities of isomerism of naphthalene compounds an established the paterns of substitutions of radicals. A second line of his research resulted in the development of the first oxazine dye, which became known as Meldola’s blue (1879). Otto Witt had demonstrated that a dye could be produced by the heating of nitrosodimethylaniline hydrochloride with m-tolylenediamine; Meldola substituted a phenol for the m-diamine and discovered a dye that colored silk a dull violet and wool a deep indigo. He published a description of the process in 1879 without his or the firm of Brooke. Simpson, and Spiller’s having taken out a patent on the process. German chemists later discovered the chemical’s value as a dye for mordanted cotton and produced the chemical commercially under the names of Neublau, Naphthalenblau, Echtblau, and Baumwollblau. Meldola’s firm, however, did take out a patent on his discovery of the first alkali green, which they exhibited at the Paris Exhibition in 1878 under the name of viridine. This became the forerunner of many sulfonated dyes of the malachite green variety.

Over an extended period commencing in 1882, Meldola also pursued research into the many complexities of azo compounds and developed a particularly novel method for reducing the nitro radicals of nitroazo compounds without reducing the azo radicals in the process. His procedures resulted in the discovery of a range of new dyes. Between 1886 and 1895 Meldola and his colleague Frederick William Streatfeild at Finsbury College wrestled, only partly successfully, with the little-understood problems of isomrism of diazoamine compounds. Toward the end of his career, he turned to the chemistry of nitro compounds and to aromatic substances, “which contributed considerably to our knowledge of the conditions governing the displacement of groups in aromatic compounds.”4

Natural History. Meldola’s first publications were in the area of natural history. As an avid collector of Lepidoptera and other insects, Meldola shared the joys of outings with his wife. Even at the outset, however, his interests were much broader than taxonomic. He saw the value of experimentation and of observations of insect behavior. In later life he deplored the lack of a field station in Great Britain where experimental and ethological studies could be carried out. More important. Meldola took a deep interest in the contemporary controversies over the mechanism of evolution. Although he did not subscribe to the neo-Darwinian extreme promoted by August Weismann and Alfred Russel Wallace. He was an ardent supporter of the mechanism of natural selection.

It was natural, given his interest in entomology and evolution theory, that Meldola should become an active participant in the discussions over protective coloration, warning colors, and mimicry. Although one cannot credit Meldola with any major contribution in these areas, his formal publications and frequent letters to the editor of Nature were distinguished by their analytic acumen. In 1873 he wrote a valuable analysis of protective coloration, in which he distinguished five classes of this phenomenon. Between 1871 and 1882 he exchanged over thirty letters with Charles Darwin on these and related issues. It was Darwin who encouraged Meldola to translate from the original German Weismann’s Studies in the Theory of Descent, to which Darwin added a brief preface and which Meldola embellished with numerous scholarly comments. Darwin also made him aware of Fritz Müller’s paper “Ituna and Thyridia,” which Meldola also translated and thereby introduced English naturalists to the Müllerian form of mimicry. The paper issued in an extended controversy between Darwin’s supporters and those, such as William Lucas Distant, who sought other mechanisms of evolution. Meldola sided with Wallace in finding Müllerian mimicry a powerful argument in favor of the action of natural selection. He added further support to Müller’s theory by calculating how two distasteful species might converge in pattern and by pointing out that the practice of mimicry tended to concentrate in groups of such “protected” butterflies as the danaids and heliconids. Edward B. Poulton, who also worked extensively on these problems and who became a close friend of and coworker with Meldola, later remarked that Meldola’s elaboration of Müller’s theory of mimicry “opened up a new and fruitful field in which much research is still being carried on.”5

Between 1886 and 1891 Meldola crossed swords with George J. Romanes on the issue of coadaption and particularly on Romanes’ “physiological” theory of selection. On that occasion Meldola again strongly supported the pure Darwinian explanation. In 1896, in the form of letters to the editor of Nature, Meldola reflected favorably on the Darwinian implications of Walter F. R. Weldon’s biometrical experiments on the dimensions of crab carapaces. Finally, in 1895 and 1896 he took the opportunity of his two presidential addresses before the Entomological Society of London to lecture his entomological friends against extreme empiricism and to argue for bringing physiology and chemistry to bear upon the general problems of the appearance and utility of variations.

Popularizer and Publicist. From the accounts of his students, one cannot conclude that Meldola was a master lecturer in an age that had become used to Thomas H. Huxley and John Tyndall. Nevertheless, he was admired for the clarity and forcefulness of his presentations. His lively wit and ability to tell anecdotes made him a popular after-dinner speaker. Meldola also possessed the talent to popularize chemistry in straightforward and lucid prose. He lectured to general audiences at Finsbury College, at the London Institution, and elsewhere. Some of these lectures later appeared in book form. He wrote a volume for Henry Holt’s Home Universal Library titled Chemistry, which contained no formulas but offered in an elegant fashion a complete elementary survey of the science. A lecture series at Finsbury Technical College, given to practical photographers as well as chemistry students in the spring of 1888, was later published in Macmillan’s Nature Series as The Chemistry of Photography (1889). Meldola’s best-known popular science work grew out of a lecture given at the London Institution on 20 January 1890 and published by the Society for Promoting Christian Knowledge. Coal and What We Get from It, A Romance of Applied Science (1891) was both historical and descriptive of the contemporary knowledge of coal tar chemistry. It did not spare the reader the names of many of the complex organic derivatives but presented the technical material in such a captivating manner that the volume went through four editions. From 1897 to 1898 Meldola also served as the editor of Arnold’s Practical Science Manuals.

By the end of the century, Meldola had become a harsh critic of the lack of a governmental policy toward science and of industry’s indifference to research. This combination of attitudes had allowed Germany to capitalize upon the chemistry of coal tar in a way that Great Britain, the natural beneficiary of recent chemical discoveries, had not done, Beginning in 1886, in an address to the Society of Arts, Meldola assumed the role of gadfly to the English dye industry, By 1910, in a talk before the Society of Dyers and Colourists titled “Tinctorial Chemistry, Ancient and Modern”, he unhesitatingly fingered the cause of the decline of the nation’s lead in industrial chemistry in the face of excuses put forth by the dye industry:

It is amazing that there should have ever been any cause suggested than the true cause, which is RESEARCH, writ large! The foreign manufacturers knew what it meant and realised its importance, and they tapped the universities and technical high schools and they added research departments and research chemists to their factories, while our manufacturers were taking no steps at all, or were calmly hugging themselves into a state of false security, based on the belief that the old order under which they had been prosperous was imperishable.6

Despite the fact that he had spoken on the authority of his experience in industrial and academic chemistry, Meldola remained an unappreciated prophet of the decline of Great Britain’s chemical industry. Only with the arrival of World War I did the country shake loose its apathy and recognize the great lead that Germany had assumed in this area of science. As he told his colleagues in March 1914, in his presidential address to the Institute of Chemistry, his feeling about the situation was “one of humiliation.”7 Nevertheless, Meldola threw himself with characteristic vigor into the war effort. The Board of Trade appointed him to the Chemical Products Committee and to the Council of the “Scheme for the Organisation and Development of Scientific and Industrial Research.” In July 1915 he assumed the chairmanship of the Advisory Council of British Dyes, Ltd. As a member of the council of the Institute of Chemistry, Meldola served on a number of its wartime committees and was chairman of its important Glass Research Committee. It was during this flurry of patriotic activity that Meldola overtaxed his health and died at his home on Brunswick Square at the age of sixty-six.


1. Tom Sidney Moore and James Charles Phillip. The Chemical Society, 95.

2. James Marchant, ed., Raphael Meldola. . . . 47.

3. John V. Eyre and E. H. Rodd, in Alexander Findlay and William Hobson Mills, eds., British Chemists, 111.

4.Ibid., 122.

5. Edward B. Poulton, “Raphael Meldola, 1849–1915,” in Proceedings of the Royal Society, A93 (1916–1917), 35.

6. Quoted in Marchant, ed., 59–60.

7. Quoted in ibid., 61.


I. Original Works. Meldola’s complete bibliography (in Marchant) contains 453 separate listings of books, articles, and published reports. These cover a wide range of subjects from chemistry and natural history to miscellaneous accounts in archaeology, geology, astronomy, and science education and organization. The most important items have been annotated by the compilers. The overwhelming majority of Meldola’s chemical papers appeared in Chemical News, Journal of the Chemical Society, and Berichte der deutschen chemischen Gesellschaft. The first description of “Meldola’s blue” appears in Einwirkung von Nitrosodimethylanilin auf Phenole, welche die Methylgruppe enthalten,” in Berichte, 12 (1879), 2065-2066; the first description of viridine appears in “Ueber die Einwirkung des Benzylchlorids auf Diphenylamin,” in Berichte, 14 (1881), 1385–1386. Meldola’s translation of Fritz Müller. “Ituna and Thyridia: a Remarkable Case of Mimicry in Butterflies,” is in Proceedings of the Entomological Society (1879), 20; his extension of Müller’s theory is “Mimiery Between Butterflies of Protected Genera,” in Annual Magazine of Natural History, 5 ser., 10 (1882), 417–425. Other important writings on the evolution of protective coloration and mimicry include “On a Certain Class of Cases of Variable Protective Colouring in Insects,” in Proceedings of the Zoological Society (1873), 153–162; and “Entomological Notes Bearing on Evolution,” in Annual Magazine of Natural History, 5 ser., 1 (1878), 155–161. Meldola’s two presidential addresses to the Entomological Society include the formal papers “Speculative Method of Entomology” and “The Utility of Specific Characters and Physiological Correlation,” which appear in the Proceedings of the society (1895), xlviii–lxviii, and (1896), lxii–xcii, respectively.

The translation and annotations of August Weismann’s important work on evolution appeared as Studies in the Theory of Descent, Raphael Meldola, trans, and ed., prefatory notice by Charles Darwin, 2 vols. (London, 1882; repr. New York, 1975). Meldola’s Oxford address, “Evolution, Darwinian and Spencerian,” first published in 1910 by the university, has become more accessible in Herbert Spencer Lectures. Decennial Issue 1905–1914 (Oxford, 1916). Meldola’s popular works include The Chemistry of Photography (London, 1889; repr. 1891, 1901); Coal and What We Get from It. A Romance of Applied Science (London, 1891); and Chemistry (New York, 1912; 2nd rev. ed., London, 1937). Darwin’s letters to Meldola are in Edward B. Poulton. Charles Darwin and the Theory of Natural Selection (London, 1896, repr. New York, 1902) 199–218.

II. Secondary Literature. The most useful obituaries of Meldola are Sir William A. Tilden and Edward B. Poulton. “Raphael Meldola, 1849–1915,” in Proceedings of the Royal Society, A93 (1916–1917), 29–37, with portrait. Both obituaries are reprinted, without the portrait, in Journal of the Chemical Society, 111 , Transactions (1917), 349–359. Shorter versions of these obtituaries appear in Nature, 96 (1915), 345–347. The most detailed account of Meldola’s chemical achievements, by John V. Eyre and E. H. Rodd, is in Alexader Findlay and William Hobson Mills, eds., British Chemists (London, 1947), 96–125. This essay includes a photograph taken around 1907. Twenty-three of Meldola’s former colleagues, students, and friends wrote memorial accounts of various aspects of Meldola’s life, which appear in James Marchant, ed., Raphael Meldola. . . Reminiscences of His Worth and Work by Those Who Knew Him, Together with a Chronological List of His Publications. . . (London, 1916). This volumes also contains resolutions of sympathy sent to Mrs. Meldola by the many organizations and institutions with which her husband had been associated. Finally, this work also contains a complete bibliography of Meldola’s writings, arranged both chronologically and by subject.

For an extended discussion of Meldola’s involvement in controversies over the significance of Müllerian mimicry and on the evolutionary debates in the Entomological Society of London, see Muriel L. Blaisdell, “Darwinism and Its Data: The Adaptive Coloration of Animals” (Ph.D. diss., Harvard University, 1976), 186–241, 281–302. Information about Meldola’s activities in various chemical societies may be gleaned from Tom Sidney Moore and James Charles Philip. The Chemical Society 1841–1941. A Historical Review (London, 1947). passim: and Richard B. Pilcher, comp., The Institute of Chemistry of Great Britain and Ireland. . . History of the Institute: 1877–1914 (London, 1914), 249–282. A third portrait of Meldola is included in this latter work.

Frederick B. Churchill

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