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Crookes, Sir William (1832-1919)

Crookes, Sir William (1832-1919)

One of the greatest physicists of the last century and an early exponent of scientific investigation of psychic phenomena. William Crookes was born June 17, 1832, in London, England, and educated at Chippenhurst Grammar School and the Royal College of Chemistry, London. Even without a graduate education, he became one of the most decorated scientists of his era.

In 1855 he became superintendent of the Meterological Department, Radcliffe Observatory, Oxford. In 1861 he made his first great discovery, the element thallium. Two years later, he became an Elected Fellow of the Royal Society.

Crookes seems to have been led into research on Spiritualism because of the untimely death of his brother Philip in 1867. He first came into contact with psychic phenomena in July 1869 in a sitting with Mary Marshall. He was further intrigued by trance speaker J. J. Morse in December, and in July 1870, after the arrival of Henry Slade in London, he announced his intention to investigate the phenomena of Spiritualism. In an early article (1870), he declares:

"Views or opinions I cannot be said to possess on a subject I do not pretend to understand. I prefer to enter upon the inquiry with no preconceived notions whatever as to what can or cannot be, but with all my senses alert and ready to convey information to the brain; believing, as I do, that we have by no means exhausted all human knowledge or fathomed the depths of all the physical forces."

The investigation had been suggested to him "by eminent men exercising great influence on the thought of the country." Another sentence of the article throws light on his expectations:

"The increased employment of scientific methods promote exact observation and greater love of truth among inquirers, and will produce a race of observers who will drive the worthless residuum of spiritualism hence into the unknown limbo of magic and necromancy."

Newspaper reporters received the announcement with jubilation. It was taken for granted that Spiritualism would be shown as clear and simple humbug. They were disappointed. The investigation began in May 1871, after the return of D. D. Home from Russia. It was witnessed by Crookes's chemical assistant, Williams; his brother Walter; Sir William Huggins, the eminent physicist and astronomer, and ex-president of the Royal Society; and Sergeant E. W. Cox, a prominent lawyer.

The secretaries of the Royal Society refused Crookes's invitation to participate. His report was submitted to the Royal Society on June 15, 1871, but his communications were refused because they did not demonstrate the fallacy of the alleged marvels of Spiritualism. Even the inscription of the title of the paper in the society's publications was denied.

It was only from the July 1871 issue of the Quarterly Journal of Science that the public became acquainted with the first account of Crookes's observations. This account contained the description of a séance held at Crookes's house in a well lit room, in which the alteration of the weight of bodies and the playing of an accordion without hands was attested by specially designed apparatus. Said Crookes, "Of all the persons endowed with a powerful development of this Psychic Force Mr. Daniel Dunglas Home is the most remarkable, and it is mainly owing to the many opportunities I have had of carrying on my investigation in his presence that I am enabled to affirm so conclusively the existence of this force."

In a subsequent article, "Notes of an Enquiry into the Phenomena Called Spiritual, during the years 1870-73," (Quarterly Journal of Science, January 1874), Crookes observes,

"The phenomena I am prepared to attest are so extraordinary, and so directly oppose the most firmly rooted articles of scientific beliefamongst others, the ubiquity and invariable action of the force of gravitationthat, even now, on recalling the details of what I witnessed, there is an antagonism in my mind between reason, which pronounces it to be scientifically impossible, and the conciousness that my senses, both of touch and sightand these corroborated, as they were, by the senses of all who were presentare not lying witnesses when they testify against my preconceptions."

The description of these experiments and the summary produced a furious anonymous attack, now known to have emanated from Dr. W. B. Carpenter, in the October 1871 issue of the Quarterly Review. The article described Crookes as a "specialist of the specialists," an investigator whose ability was "purely technical," and added, "We speak advisedly when we say that the Fellowship of the Royal Society was conferred on him with considerable hesitation." (In a special resolution the council of the Royal Society expressed its regret over this statement.)

Many other scientists questioned the experiments on every conceivable ground. Balfour Stewart in Nature (July 3, 1871) referred to the illusions produced by mesmerists and conjectured that the observers had been fooled. E. B. Tyler quoted Alfred Russel Wallace, who suggested, for a different purpose, that the werewolf superstition might have been due to mesmeric influence. Extending the suggestion to Spiritualistic marvels, he conjectured that Home and Agnes Guppy might have been werewolves, capable of influencing sensitive spectators.

But nothing could shake Crookes' belief in the accuracy of his scientific observations. He continued his experiments, and in an article in the January 1874 issue of the Quarterly Journal of Science, he gave a detailed account of all the phenomena he had tested.

While Crookes's report of 1874, based chiefly on experiments with D. D. Home and Kate Fox, was met with skepticism, accounts of his next adventure, attempting to establish the separate existence of the medium (Florence Cook, 1856-1904) and the materialized spirit ("Katie King" ), would stretch their credulity to the breaking point.

Crookes held a series of sittings with the young and beautiful "Florrie" between December 1873 and May 21, 1874. As part of his observations of Cook and King, he measured the difference in height, noted the absence of a blister on Katie's neck, the absence of perforation in Katie's ears, and the difference in complexion, bodily proportion, manner, and expression. He had himself photographed with Katie King and Florence Cook in the same position and while his picture was the same in the two photographs, the discrepancy between the girls' photos was obvious. Later Crookes reported that he had been allowed to enter the study with Katie and saw, by the light of a phosphorus lamp, the medium in trance, while Katie was standing by her side. Another time, in the full blaze of the electric light, Katie and Cook were seen together by Crookes and eight other people.

Forty-four photographs showed differences between the medium and the apparition. In a letter published in The Spiritualist (June 5, 1874), Crookes describes the photographing of Katie King:

"But photography is as inadequate to depict the perfect beauty of Katie's face, as words are powerless to describe her charms of manner. Photography may, indeed, give a map of her countenance, but how can it reproduce the brilliant purity of her complexion, or the ever-varying expression of her most mobile features, now overshadowed with sadness when relating some of the bitter experiences of her past life, now smiling with all the innocence of happy girlhood when she had collected my children round her, and was amusing them by recounting anecdotes of her adventures in India?

   Round her she made an atmosphere of life;
   the very air seemed lighter from her eyes,
   They were so soft and beautiful, and rife
   With all we can imagine of the skies;
   Her overpowering presence makes you feel
   It would not be idolatory to kneel."

In the same letter, Crookes deals with accusations of fraud on the part of Cook:

"Every test that I have proposed she has at once agreed to submit to with the utmost willingness; she is open and straightforward in speech, and I have never seen anything approaching the slightest symptom of a wish to deceive. Indeed, I do not believe she could carry on a deception if she were to try, and if she did she would certainly be found out very quickly, for such a line of action is altogether foreign to her nature."

After the Cook experiments, Crookes conducted another set of experiments in his home with the American medium Annie Eva Fay. She produced a variety of psychokinetic effects and Crookes wrote a favorable report on her which was published in the March 12, 1875, issue of The Medium. In 1876 Fay faced the first of a series of exposures and ultimately finished her career as a stage magician.

After the Fay examination, Crookes abandoned the attempt to validate psychic phenomena by scientific method and concentrated on his more conventional scientific research, although from time to time affirming that he would not retract his earlier endorsement of psychic phenomena. He served as president of the Society for Psychical Research (SPR) for the years 1896-99. It was not generally known, however, that from time to time he attended séances, and at one of these, around 1916, the spirit of his late wife apparently manifested.

Crookes went on to become one of England's most celebrated and decorated scientists. He was awarded the Royal Gold Medal (1875), the Davy Medal (1888), and the Sir Joseph Copley Medal (1904). He was knighted in 1897 (while president of the SPR) and received the Order of Merit in 1910. At different times he served as president of the Royal Society, the Chemical Society, the Institution of Electrical Engineers, and the British Association. The honors were acknowledgment of his numerous scientific accomplishments, including invention of the radiometer, the spinthariscope, and the Crookes tube, the precursor to modern television. He was the founder of the Chemical News, and editor of Quarterly Journal of Science.

In the mid-1870s, Crookes abandoned his attempt to convince his scientific peers of the truth of his observations, but he never withdrew or modified his opinions. He responded to the fury of the controversy and became cautious. For example, he never allowed the circulation of a photograph in which he stood arm-in-arm with Katie King. In a letter to Angelo Brofferio in 1894 he said, "All that I am concerned in is that invisible and intelligent beings exist who say that they are the spirits of dead persons. But proof that they really are the individuals they assume to be I have never received" (Für den Spiritismus, Leipzig, 1894).

Before the British Association at Bristol in his presidential address in 1898, Crookes declared:

"Upon one other interest I have not yet touchedto me the weightiest and farthest-reaching of all. No incident in my scientific career is more widely known than the part I took many years ago in certain psychic researches. Thirty years have passed since I published an account of experiments tending to show that outside our scientific knowledge there exists a Force exercised by intelligence differing from the ordinary intelligence common to mortals. I have nothing to retract. I adhere to my already published statements. Indeed, I might add much thereto."

As late as 1917, in an interview published in The International Psychic Gazette, he reiterated: "I have never had any occasion to change my mind on the subject. I am perfectly satisfied with what I have said in earlier days. It is quite true that a connection has been set up between this world and the next."

The Continuing Controversy

While much of the controversy surrounding Crookes died as he withdrew from further psychical research, it never entirely disappeared. On occasion throughout his later life Crookes was questioned about his opinions on psychic phenomena.

No matter what extensive precautions Crookes employed, his results, in the eyes of the skeptics, were always unevidential. Charles Richet in his Thirty Years of Psychical Research (1923), published several years after Crookes's death, defended his colleague: "Until I had seen [Eusapia Palladino ] at Milan I was absolutely sure that Crookes must have fallen into some terrible error. And so was [Julien] Ochorowicz; but he repented, and said, as I do, smiting my breast "Pater, peccavi."

The accusations against Crookes were fed by the fact that Mary Showers who occasionally had performed joint séances (including one for Crookes, with Cook)was later caught in a fraudulent materialization attempt and that Cook herself was caught cheating on two occasions in 1880 and 1889.

Cook continued to operate as a medium through the rest of the century and her sister Katie Cook succeeded her.

The most damaging allegations were made in June 1922, long after the death of Florence Cook. Francis G. H. Anderson, called at the offices of the Society for Psychical Research (SPR), London, and made a statement to E. J. Dingwall, then the research officer of the society, that he had had an affair with Cook many years ago, and that one night she told him that her mediumship was fraudulent. Further more, he testified that she had confided in him that she had had an affair with William Crookes, and the famous séances were staged as a cover. In 1949 Anderson repeated and expanded his story to Mrs. K. M. Goldney of the Society for Psychical Research.

Assuming his recollection of what Florence Cook said was reasonably accurate, the claim that the mediumship was fraudulent carried more weight than charges that William Crookes had been an accomplice in order to carry on a love affair. Crookes's defenders argued that, if the materialization of Katie King was fraudulent, it is more likely that Crookes was deceived. He became convinced of the reality of the phenomena of Home. Also, some of the Cook séances were conducted at Crookes' own home, near his wife and children. Crookes wrote enthusiastic letters to the press about the séances, openly admitting that he embraced the phantom Katie King, which appeared as flesh and blood. He took photographs of himself and the phantom. None of these actions seem consistent with organizing the séances as a cover for a love affair.

The view that Crookes was simply duped by (rather than an accomplice with) the mediums he tested was given weight by Houdini, who in his book claimed that Fay described to him the way she had gotten around all of Crookes's gadgets and tricked him.

The controversy was continued in 1962 when Trevor H. Hall, in his book The Spiritualists, presented persuasive evidence that Cook was fraudulent, and also repeated Anderson's claims that Crookes connived at fraud to hide a love affair with her.

Crookes did not hide his attraction to Cook's beauty. Hall built his case more upon Cook's association with Showers, who, he suggests, was possibly an accomplice in fraud. Showers also claimed to materialize spirit forms, in particular the phantom "Florence Maple," which reportedly had the same substantiality as Florence Cook's "Katie King."

Showers and Cook gave a joint demonstration at the house of William Crookes in March 1874, when the spirit forms Florence Maple and Katie King walked around the room outside the cabinet, linked arm in arm, laughing and talking like real human beings. E. W. Cox, who was present at this astonishing séance, expressed his extreme skepticism in a letter published in The Spiritualist (May 15, 1874). In a letter to Home in November 1875, Crookes stated Showers had confessed to Fay that she was a fraud, and he had later obtained a written confession from Showers. Fraud on the part of Showers provided valid doubts on the genuineness of the phenomena of Cook. Whether Crookes can be regarded as an accomplice in such fraud in order to carry on an illicit love affair with Cook is a separate issue.

Many find it is hard to believe that Crookes, with his reputation as a scientist at stake, would make such imprudent statements as he made if he was indeed an accomplice in fraud for the sake of sexual favors. Others find it just as hard to believe that Crookes was deceived by the "innocent schoolgirl," who would have to have been a remarkable actress, capable of outwitting Crookes's tests and sustaining a phantom role with a variety of anecdotes of a past life in foreign countries.

Crookes was certainly fascinated by Katie King and/or Florence Cook. It may be that his fascination overrode his scientific and personal judgment. Cook may have mesmerized him much as Madame Blavatsky dazzled Henry Steel Olcott with her apparently miraculous powers. If Anderson's recollection is correct, Cook's claim of an illicit love affair may have been no more than a boastful recollection of the glamour cast over Crookes by Katie King, especially Crookes's public embracing of the phantom.

It is likely that Crookes's career in psychical research and his relation to Cook will remain a topic of discussion in parapsychological circles. In the last generation the discussion has shifted as the defenders of physical phenomena, especially materialization, have retreated from the scene.

Crookes died on April 4, 1919, in London.


Berger, Arthur S., and Joyce Berger. The Encyclopedia of Parapsychology and Psychical Research. New York: Paragon House, 1991.

Crookes, William. "Address by the President." Proceedings of the Society for Psychical Research 12 (1896): 338.

. "Notes of an Enquiry into the Phenomena called Spiritual." Quarterly Journal of Science (January 1874).

. Researches in the Phenomena of Spiritualism. London, 1874.

. Researches in Spiritualism. London: J. Burnes, 1875.

. "Spiritualism Viewed by the Light of Modern Science." Quarterly Journal of Science 7 (July 1870).

Dingwall, E. J. The Critics' Dilemma: Further Comments on Some Nineteenth Century Investigations. Dewsbury, England: The Author, 1966.

Fournier d'Albe, E. E. The Life of Sir William Crookes, O.M., F.R.S. London: T. F. Unwin, 1923.

Hall, Trevor. Florence Cook & William Crookes: A Footnote to an Enquiry. London: Tomorrow Publications, 1963.

. The Spiritualists: The Story of Florence Cook and William Crookes. New York: Helix Press, 1963. Reprinted as The Medium and the Scientist. Buffalo, N.Y: Prometheus Press, 1984.

Medhurst, R. G. Crookes and the Spirit World. London: Taplinger, 1972.

Medhurst, R. G., and K. M. Godney. "William Crookes and the Physical Phenomena of Mediumship." Proceedings of the Society for Psychical Research 54, 195 (March 1964).

Thouless, R. H. "Crookes and Cook." Journal of the Society for Psychical Research 42 (1963).

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Sir William Crookes

Sir William Crookes

The English chemist and physicist Sir William Crookes (1832-1919) discovered the element thallium and invented the radiometer, the spinthariscope, and the Crookes tube.

William Crookes was born in London on June 17, 1832. His education was limited, and despite his father's wish that he become an architect, he chose industrial chemistry as a career. He entered the Royal College of Chemistry in London, where he began his researches in chemistry. In 1859 he founded the Chemical News, which made him widely known, and remained its editor and owner all his life.

Most notable among Crookes's chemical studies is that one which led to his 1861 discovery of thallium. Using spectrographic methods, he had observed a green line in the spectrum of selenium, and he was thus led to announce the existence of a new element, thallium. While determining the atomic weight of thallium, using a delicate vacuum balance, he noticed several irregularities in weighing, which he attributed to the method. His investigation of this phenomenon led to the construction in 1875 of an instrument that he named the radiometer.

In 1869 J. W. Hittorf first studied the phenomena associated with electrical discharges in vacuum tubes. Not knowing of this, Crookes, 10 years later, made a parallel but more extensive investigation. In his 1878 report he pointed out the significant properties of electrons in a vacuum, including the fact that a magnetic field causes a deflection of the emission. He suggested that the tube was filled with matter in what he called the "fourth state;" that is, the mean free path of the molecules is so large that collisions between them can be ignored. Tubes such as this are still called "Crookes tubes," and his work was honored by naming the space near the cathode in low pressure "Crookes dark space."

Crookes also made useful contributions to the study of radioactivity in 1903 by developing the spinthariscope, a device for studying alpha particles. He foresaw the urgent need for nitrogenous fertilizers, which would be used to cultivate crops to meet the demands of a rapidly expanding population. Crookes did much to popularize phenol (carbolic acid) as an antiseptic; in fact, he became an expert on sanitation. Mention should also be made of the serious and active interest he took in psychic phenomena, to which he devoted most of 4 years.

Crookes was knighted in 1897. His marriage lasted from 1856 until the death of his wife in 1917; they had 10 children. He died in London on April 4, 1919.

Further Reading

A biography of Crookes is Edmund E. Fournier d'Albe, The Life of Sir Wm. Crookes (1923). For background information see Alexander Findlay, A Hundred Years of Chemistry (1937; 3d ed. 1965), and Eduard Farber, The Evolution of Chemistry: A History of Its Ideas, Methods and Materials (1952; 2d ed. 1969).

Additional Sources

Hall, Trevor H., The medium and the scientist: the story of Florence Cook and William Crookes, Buffalo, N.Y.: Prometheus Books, 1984. □

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Crookes, Sir William

Sir William Crookes, 1832–1919, English chemist and physicist. After serving at the Radcliffe Observatory, Oxford, and teaching chemistry at Chester Training College, he retired to work in his own laboratory in London. He discovered the element thallium and made special studies of radioactive substances in the course of which he invented the spinthariscope, used to make visible the flashes produced by bombarding a screen with the alpha rays of a particle of radium, and he devised the radiometer, which measures the intensity of radiant energy. He also intensively studied the rare earths and diamonds. Crookes devised spectacles to protect the eyes of glassworkers from damaging rays. One of his chief inventions is the Crookes tube, with which J. J. Thomson, W. C. Roentgen, R. A. Millikan, and others conducted important research. He founded the Chemical News in 1859 and was the author of numerous scientific papers and of Select Methods in Chemical Analysis (1871). Crookes was also interested in psychical research.

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Crookes, Sir William

Crookes, Sir William (1832–1919) English chemist and physicist. He invented the radiometer (which measures electromagnetic radiation) and the Crookes tube, which led to the discovery of the electron by J. J. Thomson. Crookes was the first to suggest that cathode rays consist of negatively charged particles. He also discovered thallium. See also X-ray

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