Thomas Ralph Merton

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Sir Thomas Ralph Merton KBE, DSc, FRS [1] (12 January 1888 – 10 October 1969) was an English physicist, inventor and art collector. He is particularly noted for his work on spectroscopy and diffraction gratings.

Order of the British Empire British order of chivalry

The Most Excellent Order of the British Empire is a British order of chivalry, rewarding contributions to the arts and sciences, work with charitable and welfare organisations, and public service outside the civil service. It was established on 4 June 1917 by King George V and comprises five classes across both civil and military divisions, the most senior two of which make the recipient either a knight if male or dame if female. There is also the related British Empire Medal, whose recipients are affiliated with, but not members of, the order.

Doctor of Science, usually abbreviated Sc.D., D.Sc., S.D., or D.S., is an academic research degree awarded in a number of countries throughout the world. In some countries, "Doctor of Science" is the title used for the standard doctorate in the sciences; elsewhere the Sc.D. is a "higher doctorate" awarded in recognition of a substantial and sustained contribution to scientific knowledge beyond that required for a Doctor of Philosophy (PhD). It may also be awarded as an honorary degree.

Fellow of the Royal Society Elected Fellow of the Royal Society, including Honorary, Foreign and Royal Fellows

Fellowship of the UK Royal Society is an award granted to individuals that the Royal Society of London judges to have made a 'substantial contribution to the improvement of natural knowledge, including mathematics, engineering science, and medical science'.


Early life and education

Born in Wimbledon, Surrey, Thomas Ralph Merton was the only son of Emile Ralph Merton and Helen, daughter of Thomas Meates, a descendant of Sir Thomas Meutas, Secretary to Sir Francis Bacon. Emile Merton was for a time in the family metal trading business as a partner in Henry R. Merton & Co. which was started in London by his eldest brother in 1860. Another brother William Ralph Merton founded the Metallgesellschaft in Frankfurt-am-Main in 1881, which became the second largest company in Germany and the largest non-ferrous mining company in the world. The two companies worked closely with one another, along with the American Metal Company in New York City.

Wimbledon, London Suburb of London

Wimbledon is a district and town of south-west London, England, 7.1 miles (11.4 km) south-west of the centre of London at Charing Cross, in the London Borough of Merton, south of Wandsworth, north-east of New Malden, north-west of Mitcham, west of Streatham and north of Sutton. Wimbledon had a population of 68,187 in 2011 which includes the electoral wards of Abbey, Dundonald, Hillside, Trinity, Village, Raynes Park and Wimbledon Park.

Surrey County of England

Surrey is a county in South East England which borders Kent to the east, West Sussex to the south, Hampshire to the west, Berkshire to the northwest, and Greater London to the northeast.

Metallgesellschaft AG was formerly one of Germany's largest industrial conglomerates based in Frankfurt. It had over 20,000 employees and revenues in excess of 10 billion US dollars. It had over 250 subsidiaries specializing in mining, specialty chemicals (Chemetall), commodity trading, financial services, and engineering (Lurgi). Henry Merton & Company, Ltd was previously a branch of the Metallgesellschaft.

Thomas was educated at Farnborough School and Eton College, where Dr T. C. Porter, the physics master, encouraged him to begin research. Between leaving Eton in 1905 and going up to Balliol College, Oxford, in 1906, he worked at King's College London. He went to Balliol with distinguished fellow Etonians Julian Grenfell, Ronald Knox, and Julian Huxley.

Eton College British independent boarding school located in Eton

Eton College is a 13–18 independent boarding school and sixth form for boys in the parish of Eton, near Windsor in Berkshire, England. It was founded in 1440 by King Henry VI as Kynge's College of Our Ladye of Eton besyde Windesore , as a sister institution to King's College, Cambridge, making it the 18th-oldest Headmasters' and Headmistresses' Conference school.

Oxford City and non-metropolitan district in England

Oxford is a university city in Oxfordshire, England, with a population of 155,000. It is 51 miles (82 km) northwest of London, 57 miles (92 km) from Birmingham and 30 miles (48 km) from Reading.

Kings College London public research university located in London, United Kingdom

King's College London is a public research university located in London, United Kingdom, and a founding college and member institution of the federal University of London. King's was established in 1829 by King George IV and Arthur Wellesley, 1st Duke of Wellington, when it received its first royal charter, and claims to be the fourth oldest university institution in England. In 1836, King's became one of the two founding colleges of the University of London. In the late 20th century, King's grew through a series of mergers, including with Queen Elizabeth College and Chelsea College of Science and Technology, the Institute of Psychiatry, the United Medical and Dental Schools of Guy's and St Thomas' Hospitals and the Florence Nightingale School of Nursing and Midwifery.

In view of his delicate health and his promise as a scientist, Oxford allowed Merton to go straight to a research thesis without taking his final exams; this was an unusual privilege. His investigation of the properties of solutions of caesium nitrate earned him a BSc in 1910. Meanwhile, he had been reading widely and conceived many ideas for improving the techniques of spectroscopy. While still a schoolboy he had set up a room in his father's house as a primitive laboratory.

Scientist Person that studies a science

A scientist is someone who conducts scientific research to advance knowledge in an area of interest.

Caesium Chemical element with atomic number 55

Caesium is a chemical element with the symbol Cs and atomic number 55. It is a soft, silvery-golden alkali metal with a melting point of 28.5 °C (83.3 °F), which makes it one of only five elemental metals that are liquid at or near room temperature. Caesium has physical and chemical properties similar to those of rubidium and potassium. The most reactive of all metals, it is pyrophoric and reacts with water even at −116 °C (−177 °F). It is the least electronegative element, with a value of 0.79 on the Pauling scale. It has only one stable isotope, caesium-133. Caesium is mined mostly from pollucite, while the radioisotopes, especially caesium-137, a fission product, are extracted from waste produced by nuclear reactors.

Nitrate anion

Nitrate is a polyatomic ion with the molecular formula NO
and a molecular mass of 62.0049 u. Organic compounds that contain the nitrate ester as a functional group (RONO2) are also called nitrates.

In 1912 he married (Violet) Marjory, the charming and accomplished daughter of Lt.-Colonel W. H. Sawyer, and moved with his laboratory in tow to his London house, on Gilbert Street. Theirs was an exceptionally happy partnership, which lasted for 57 years, during which they were never separated for more than a few days.

Spectroscopy research: 19131928

After 1913 a steady stream of papers came from Merton's private laboratory, in which he assembled the latest spectroscopic equipment. His early work was on the absorption spectra of solutions, but he soon changed to the spectra of gases and to astrophysics, which were to be the main fields of his investigations. His early papers were distinguished by the beauty and accuracy of his experimental techniques. In 1916 he obtained his DSc from Oxford and was appointed lecturer in spectroscopy at King's College London. In the same year his first joint paper with his friend J. W. Nicholson appeared. It was a fortunate chance which brought together Nicholson's brilliant mathematical analysis and Merton's experimental skill. The paper dealt with the broadening of spectral lines in a condensed discharge. By an ingenious technique Merton measured the discontinuities in the lines due to their partial breaking up into components under the influence of the magnetic field between adjacent atoms. The two men applied the same technique to the measurement of the spectra of hydrogen and helium, reproducing the distribution of intensity of some stellar lines in the laboratory for the first time.

Astrophysics is the branch of astronomy that employs the principles of physics and chemistry "to ascertain the nature of the astronomical objects, rather than their positions or motions in space". Among the objects studied are the Sun, other stars, galaxies, extrasolar planets, the interstellar medium and the cosmic microwave background. Emissions from these objects are examined across all parts of the electromagnetic spectrum, and the properties examined include luminosity, density, temperature, and chemical composition. Because astrophysics is a very broad subject, astrophysicists apply concepts and methods from many disciplines of physics, including classical mechanics, electromagnetism, statistical mechanics, thermodynamics, quantum mechanics, relativity, nuclear and particle physics, and atomic and molecular physics.

Spectral line optical phenomenon

A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from emission or absorption of light in a narrow frequency range, compared with the nearby frequencies. Spectral lines are often used to identify atoms and molecules. These "fingerprints" can be compared to the previously collected "fingerprints" of atoms and molecules, and are thus used to identify the atomic and molecular components of stars and planets, which would otherwise be impossible.

Magnetic field spatial distribution of vectors allowing the calculation of the magnetic force on a test particle

A magnetic field is a vector field that describes the magnetic influence of electric charges in relative motion and magnetized materials. The effects of magnetic fields are commonly seen in permanent magnets, which pull on magnetic materials and attract or repel other magnets. Magnetic fields surround and are created by magnetized material and by moving electric charges such as those used in electromagnets. They exert forces on nearby moving electrical charges and torques on nearby magnets. In addition, a magnetic field that varies with location exerts a force on magnetic materials. Both the strength and direction of a magnetic field vary with location. As such, it is described mathematically as a vector field.

In 1919 Balliol elected Merton to a research fellowship and Oxford made him reader (from 1923 professor) in spectroscopy. He worked on a series of problems, usually with a young student as his assistant. He was elected to the Royal Society in 1920 [1] and in 1922, with Sydney Baratt, gave the society's Bakerian lecture, on the spectrum of hydrogen. They cleared up a number of discrepancies in the secondary spectrum of hydrogen which were shown to be due to the hydrogen molecule, and they also showed the profound influence that traces of impurities can exert on gas spectra. In 1923 Merton left Oxford to live at Winforton House in Herefordshire, the estate he had acquired with 3 miles of salmon fishing on the Wye. He was a good shot and a most skilful fisherman. He transferred his laboratory to Winforton, so that he was able to combine a sporting life with his scientific research.

Balliol College, Oxford constituent college of the University of Oxford

Balliol College is one of the constituent colleges of the University of Oxford in England. One of Oxford's oldest colleges, it was founded around 1263 by John I de Balliol, a rich landowner from Barnard Castle in County Durham, who provided the foundation and endowment for the college. When de Balliol died in 1269 his widow, Dervorguilla, a woman whose wealth far exceeded that of her husband, continued his work in setting up the college, providing a further endowment, and writing the statutes. She is considered a co‑founder of the college.

Royal Society English learned society for science

The President, Council and Fellows of the Royal Society of London for Improving Natural Knowledge, commonly known as the Royal Society, is a learned society. Founded on 28 November 1660, it was granted a royal charter by King Charles II as "The Royal Society". It is the oldest national scientific institution in the world. The society is the United Kingdom's and Commonwealth of Nations' Academy of Sciences and fulfils a number of roles: promoting science and its benefits, recognising excellence in science, supporting outstanding science, providing scientific advice for policy, fostering international and global co-operation, education and public engagement.

Herefordshire County of England

Herefordshire is a county in the West Midlands of England, governed by Herefordshire Council. It borders Shropshire to the north, Worcestershire to the east, Gloucestershire to the south-east, and the Welsh counties of Monmouthshire and Powys to the west.

The First 'Q' in MI6

The First World War scarcely interrupted his research activity. Having been rejected for active service on grounds of health, he was commissioned in 1916 as a lieutenant in the Royal Naval Volunteer Reserve. In 1915, he was handpicked by Sir Mansfield Smith-Cumming to work for MI6, the first such scientist to be appointed by the newly created organisation. He conducted various ink experiments with many different chemical solutions, including potassium permanganate, antipyrine and sodium nitrate. Spies were also advised to make invisible ink from semen. However, this was eventually abandoned because of complaints about the smell from those receiving the letters. His success in identifying the secret ink carried by German spies in their clothing, and inventing a new means of secret writing, won a mention in dispatches.

Contribution to diffraction gratings

There is a gap of nearly twenty years between Merton's scientific papers of 1928 and 1947. In this interval he was busy in the laboratory and was taking out patents for his inventions. Diffraction gratings were one of his lifelong interests and here his inventive genius best showed itself. The rarity and expense of good diffraction gratings led him to devise, in 1935, a method of copying them without loss of optical quality, by applying a thin layer of a cellulose ester solution to an original plane grating. When the solvent had evaporated he detached this pellicle and applied its grooved surface to a moist gelatine film on a glass plate. When dry, the gelatine bore a faithful record of the original rulings.

In 1948 Merton made an important basic advance in the art of ruling diffraction gratings. Since 1880 these had been ruled groove by groove by the method used by Rowlands. In place of this, Merton ruled a very fine helix continuously on a steel cylinder which he then opened out upon a plane gelatine-coated surface by his copying method. No lathe could, however, rule a helix free from errors of pitch and these Merton eliminated by an ingenious device. It consisted of a ‘chasing lathe’ by which he cut a secondary helix on the same cylinder with a tool mounted on a ‘Merton nut’ lined with strips of cork pressed upon the primary lathe-cut helix. Periodic errors were thus averaged and eliminated by the elasticity of the cork. [2]

Merton handed these processes over to the National Physical Laboratory (NPL) for further development and they formed the basis of a considerable research programme. The ‘blazed’ gratings made by the Merton–NPL method were of great value in making available cheap infra-red spectrometers of high resolving power for research and industry, while long gratings ruled by this method came into use for engineering measurement and machine tool control.

Experiments with cathode rays

In the laboratory at his father's house Merton had bombarded various newly discovered phosphorescent powders with cathode rays. He was surprised to find that while all lit brilliantly, the afterglow was brief and feeble. By experiment, he discovered that this was because the excitation and emission lines of the spectra barely overlapped, and that by mixing suitable powders he could increase the afterglow. He realized that persistent afterglow could be got by a double layer of powders, in which the light emitted by the back layer excited the front layer, but as this technique seemed to have no practical use he forgot about it for thirty-three years, until 1938 when Sir Henry Tizard asked if he could achieve such a long afterglow. Merton was able to reply by return of post, and soon after was asked to join the air defence committee where he learned that his discovery had made possible the two-layer long-persistence radar screens which helped to bring victory in the Battle of Britain.

His other wartime inventions included a black paint which reduced the proportion of light reflected from bombers in a searchlight to less than one per cent; the use of nitrous oxide in the fuel to accelerate fighter aircraft; and a diffraction rangefinder for fighters, which was used against doodlebugs.

Treasurer of the Royal Society

From 1939 to 1956 Merton was treasurer of the Royal Society, where his knowledge and experience of business were of considerable benefit. He formed a committee of experts to control its finances, and it was on his initiative that charitable bodies were given power to invest in equities, where they had previously been limited to gilt-edged stock. The income of all the society's funds showed a large increase during his treasurership.

Art collection

In 1930 John, the eldest of the Mertons' five sons, brought home the drawing prize from Eton and this proved a turning point in both his and his father's lives. It awoke in Merton some latent interest and he spent months in Italy with his son seeing all the great collections of Renaissance paintings. He began to make a remarkable collection of pictures of the period 14501520. From 1944 until his death he was a member of the scientific advisory board of the National Gallery, and its chairman from 1957 to 1965. He was also a trustee of the gallery, and of the National Portrait Gallery from 1955 to 1962. Merton was knighted in 1944 for his services during the war and in 1956 was appointed KBE. He was awarded the Holweck Prize in 1951 and the Rumford medal of the Royal Society in 1958.

In making his collection Sir Thomas followed his own interests and every work in it represents the personal taste of its owner, be the subject sacred or secular. As most of the works belong to the period of 1450 to 1520, the collection has great homogeneity and, in spite of the self-imposed limit of time, great diversity of subjects and techniques. No picture has been admitted merely because of size or with the intention of filling a certain space, but each has been selected for its pigmentary quality and with the determination to exclude anything that falls short of a high standard of perfection.

Preference is given to portraits which in expression, deportment and costume, convey a very clear idea of the life, taste and colour of their period... Next come the group of devotional pictures on a small scale, intended originally for the privacy of the home rather than public worship... A few pictures fascinate by their narrative as the predella by Fungai or the three Cassoni as do the drawings by being preparatory studies for the more elaborate works.

Twenty-two of the works, including drawings, were Italian, and ten of the northern schools.

Merton's instinctive connoisseurship is indicated by the distinction of so many of his acquisitions. The clou of his Italian pictures was the Botticelli Portrait of a Youth, now on loan to the National Gallery of Art, Washington, which had been in the Newborough collection: this cost £17,000 in 1941. He owned cassone panels formerly in the collections of Otto H. Kahn and Lord Crawford, as well as Fungai's predella panel of the Martyrdom of Saint Clement, now reunited with an erstwhile companion in the City Art Gallery, York. The Madonna and Child with a Donor by Bartolommeo Montagna, now in the Walker Art Gallery, Liverpool, is one of the most beautiful of that Vicentine master's creations and was the finest picture from the collection of Dr. Alfred Mond to be withheld from his bequest to the National Gallery. Signorelli's exceptional chalk study of a young warrior was sold by private treaty through Christie's, also to the Walker Art Gallery, in 1980. Of the northern pictures seven were portraits, the earliest being the Portrait of a Man formerly believed to be Guillaume Fillastre, long on loan to the National Gallery, now thought to be by a close follower of Rogier van der Weyden: purchased for £18,500 in 1940, this was sold in lieu of taxation through Christie's in 1987 and is now in the Courtauld Institute. The Behams catalogued below, which Scharf's erroneously ascribed to Mielich, were appropriately complemented by portraits by two of the artist's German contemporaries, Cranach and Hans Krell. Sir Thomas knew how important a contribution frames could make to the impact of his pictures, and in this respect was well served by Pollak, the framer who was admired by other major collectors of his generation.

Some sense of what pictures meant to Merton is suggested in two passages in the notebook in which he recorded certain thoughts.

"'Signal to noise ratio' is a term often used in physics. In fact it applies to everything we try to understand and measure, from the precision with which the deflection of a galvanometer can be read to the amount we can grasp of a conversation at a cocktail party, where the signal is what someone is saying to us and the noise is the integrated chatter of the other guests. It applies also to the fine arts. In what is perhaps one the greatest of all works of art, Michelangelo's Pietà in St. Peter's, it is nearly all signal and no noise, while in the work of the action painters it is all noise and no signal. There is nothing new in the products of the action painters. Leonardo da Vinci in his notes says that 'if you look at any walls spotted with various stains or with a mixture of different kinds of stones, if you are about to invent some scene you will be able to see in it a resemblance to different landscapes adorned with mountains etc., etc., and an infinite number of things which you can reduce into separate and well-conceived forms.'"

"In these days of 'Do-it-yourself' we are expected to 'reduce into separate and well-conceived forms' ourselves. Some of us prefer to have it done for us by a great artist."

His collection showed that Sir Thomas could fairly be stated to have admired great artists. But his desire for possession was not unlimited:

"Pictures are like women. There are quite a number of them which one can admire without wanting to live with them."

Later life

In 1947 Merton bought Stubbings House, at Maidenhead Thicket, Berkshire. Its spacious rooms made an appropriate setting for his collection of pictures. As a man of considerable wealth, he maintained what was probably the last private physics laboratory in Britain. Papers and patents continued to appear, based on his researches there. In 1957 he had several serious operations and thereafter he rarely left his home, where he died on 10 October 1969.

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  1. 1 2 Hartley, H.; Gabor, D. (1970). "Thomas Ralph Merton. 1888-1969". Biographical Memoirs of Fellows of the Royal Society . 16: 421. doi:10.1098/rsbm.1970.0017.
  2. "Profile: Sir Thomas Merton, He Has Spent His Time So Well". New Scientist . 3 October 1957. pp. 27–28.