John Herschel

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Sir John Herschel

John Herschel 1846 (cropped).png
Drawing of John Herschel, published in 1846
Born(1792-03-07)7 March 1792
Died11 May 1871(1871-05-11) (aged 79)
Collingwood, near Hawkhurst, Kent, England
Resting place Westminster Abbey
Residence Slough
Cape Town
Education Eton College
Alma mater St John's College, Cambridge
Known forThe invention of photography
Spouse(s)Margaret Brodie Stewart
Awards Smith's Prize (1813)
Copley Medal (1821)
Lalande Medal (1825)
Gold Medal of the Royal Astronomical Society (1826), (1836)
Royal Medal (1836, 1840)
Knight of the Royal Guelphic Order
Scientific career
Influences William Herschel (father), Caroline Herschel (aunt)

Sir John Frederick William Herschel, 1st Baronet KH FRS ( /ˈhɜːrʃəl, ˈhɛər-/ ; [1] 7 March 1792 – 11 May 1871) [2] was an English polymath, mathematician, astronomer, chemist, inventor, experimental photographer who invented the blueprint, [3] [4] [5] and did botanical work. [2]

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

Fellowship of the 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'.

Polymath person whose expertise spans a significant number of different subject areas

A polymath is a person whose expertise spans a significant number of subject areas, known to draw on complex bodies of knowledge to solve specific problems.

Mathematician person with an extensive knowledge of mathematics

A mathematician is someone who uses an extensive knowledge of mathematics in his or her work, typically to solve mathematical problems.


Herschel originated the use of the Julian day system in astronomy. He named seven moons of Saturn and four moons of Uranus. He made many contributions to the science of photography, and investigated colour blindness and the chemical power of ultraviolet rays; his Preliminary Discourse (1831), which advocated an inductive approach to scientific experiment and theory building, was an important contribution to the philosophy of science. [6]

Julian day is the continuous count of days since the beginning of the Julian Period and is used primarily by astronomers, and in software for easily calculating elapsed days between two events.

Astronomy natural science that deals with the study of celestial objects

Astronomy is a natural science that studies celestial objects and phenomena. It applies mathematics, physics, and chemistry in an effort to explain the origin of those objects and phenomena and their evolution. Objects of interest include planets, moons, stars, nebulae, galaxies, and comets; the phenomena also includes supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, all phenomena that originate outside Earth's atmosphere are within the purview of astronomy. A related but distinct subject is physical cosmology, which is the study of the Universe as a whole.

Moons of Saturn The natural satellites of the planet Saturn

The moons of Saturn are numerous and diverse, ranging from tiny moonlets less than 1 kilometer across to the enormous Titan, which is larger than the planet Mercury. Saturn has 62 moons with confirmed orbits, 53 of which have names and only 13 of which have diameters larger than 50 kilometers, as well as dense rings with complex orbital motions of their own. Seven Saturnian moons are large enough to be ellipsoidal in shape, yet only two of those, Titan and Rhea, are currently in hydrostatic equilibrium. Particularly notable among Saturn's moons are Titan, the second-largest moon in the Solar System, with a nitrogen-rich Earth-like atmosphere and a landscape featuring dry river networks and hydrocarbon lakes found nowhere else in the solar system; and Enceladus since its chemical composition is similar to that of comets. In particular, Enceladus emits jets of gas and dust, which could indicate the presence of liquid water under its south pole region, and may have a global ocean below its surface.

Early life and work on astronomy

A Calotype of a model of the lunar crater Copernicus, 1842 Lunar Copernicus crater - Herschel 1842.jpg
A Calotype of a model of the lunar crater Copernicus, 1842

Herschel was born in Slough, Buckinghamshire, the son of Mary Baldwin and William Herschel. He was the nephew of astronomer Caroline Herschel. He studied shortly at Eton College and St John's College, Cambridge, graduating as Senior Wrangler in 1813. [7] It was during his time as an undergraduate that he became friends with the mathematicians Charles Babbage and George Peacock. [2] He left Cambridge in 1816 and started working with his father. He took up astronomy in 1816, building a reflecting telescope with a mirror 18 inches (460 mm) in diameter, and with a 20-foot (6.1 m) focal length. Between 1821 and 1823 he re-examined, with James South, the double stars catalogued by his father. [8] He was one of the founders of the Royal Astronomical Society in 1820. For his work with his father, he was presented with the Gold Medal of the Royal Astronomical Society in 1826 (which he won again in 1836), and with the Lalande Medal of the French Academy of Sciences in 1825, while in 1821 the Royal Society bestowed upon him the Copley Medal for his mathematical contributions to their Transactions. Herschel was made a Knight of the Royal Guelphic Order in 1831. [2]

Slough Place in England

Slough is a large town in Berkshire, England, within the Greater London Urban Area, 20 miles (32 km) west of Charing Cross, central London and 17 miles (27 km) north-east of the county town of Reading. It is between the Thames Valley and London and at the intersection of the M4, M40 and M25 motorways.

Buckinghamshire County of England

Buckinghamshire, abbreviated Bucks, is a ceremonial county in South East England which borders Greater London to the south east, Berkshire to the south, Oxfordshire to the west, Northamptonshire to the north, Bedfordshire to the north east and Hertfordshire to the east.

William Herschel 18th and 19th-century German-born British astronomer and composer

Frederick William Herschel, was a German-born British astronomer, composer and brother of fellow astronomer Caroline Herschel, with whom he worked. Born in the Electorate of Hanover, Herschel followed his father into the Military Band of Hanover, before migrating to Great Britain in 1757 at the age of nineteen.

Herschel served as President of the Royal Astronomical Society three times: 1827–29, 1839–41 and 1847–49. [9] [10]

The President of the Royal Astronomical Society chairs the Council of the Royal Astronomical Society (RAS) and its formal meetings. They also liaise with government organisations, similar societies in other countries, and the International Astronomical Union on behalf of the UK astronomy and geophysics communities. Future presidents serve one year as President Elect before succeeding the previous president.

Herschel's A preliminary discourse on the study of natural philosophy, published early in 1831 as part of Dionysius Lardner's Cabinet cyclopædia , set out methods of scientific investigation with an orderly relationship between observation and theorising. He described nature as being governed by laws which were difficult to discern or to state mathematically, and the highest aim of natural philosophy was understanding these laws through inductive reasoning, finding a single unifying explanation for a phenomenon. This became an authoritative statement with wide influence on science, particularly at the University of Cambridge where it inspired the student Charles Darwin with "a burning zeal" to contribute to this work. [11] [12] [13]

Natural philosophy ancient philosophical study of nature and physical universe that was dominant before the development of modern science. It is considered to be the precursor of natural science

Natural philosophy or philosophy of nature was the philosophical study of nature and the physical universe that was dominant before the development of modern science. It is considered to be the precursor of natural science.

Inductive reasoning is a method of reasoning in which the premises are viewed as supplying some evidence for the truth of the conclusion, this is in contrast to deductive reasoning. While the conclusion of a deductive argument is certain, the truth of the conclusion of an inductive argument may be probable, based upon the evidence given.

University of Cambridge University in Cambridge, United Kingdom

The University of Cambridge is a collegiate public research university in Cambridge, United Kingdom. Founded in 1209 and granted a Royal Charter by King Henry III in 1231, Cambridge is the second-oldest university in the English-speaking world and the world's fourth-oldest surviving university. The university grew out of an association of scholars who left the University of Oxford after a dispute with the townspeople. The two 'ancient universities' share many common features and are often referred to jointly as 'Oxbridge'. The history and influence of the University of Cambridge has made it one of the most prestigious universities in the world.

Herschel published a catalogue of his astronomical observations in 1864, as the General Catalogue of Nebulae and Clusters , a compilation of his own work and that of his father's, expanding on the senior Herschel's Catalogue of Nebulae . A further complementary volume was published posthumously, as the General Catalogue of 10,300 Multiple and Double Stars.

Herschel correctly considered astigmatism to be due to irregularity of the cornea and theorised that vision could be improved by the application of some animal jelly contained in a capsule of glass against the cornea. His views were published in an article entitled Light in 1828 and the Encyclopædia Metropolitana in 1845. [14]

Discoveries of Herschel include the galaxies NGC 7, NGC 10, NGC 25, and NGC 28

Visit to Southern Africa

Disa cornuta (L.) Sw. by Margaret & John Herschel Disa cornuta00.jpg
Disa cornuta (L.) Sw. by Margaret & John Herschel

Declining an offer from the Duke of Sussex that they travel to South Africa on a Navy ship, Herschel and his wife paid £500 for passage on the S.S. Mountstuart Elphinstone, which departed from Portsmouth on 13 November 1833.

The voyage to South Africa was made in order to catalogue the stars, nebulae, and other objects of the southern skies. [2] This was to be a completion as well as extension of the survey of the northern heavens undertaken initially by his father William Herschel. He arrived in Cape Town on 15 January 1834 and set up a private 21 ft (6.4 m) telescope at Feldhausen at Claremont, a suburb of Cape Town. Amongst his other observations during this time was that of the return of Comet Halley. Herschel collaborated with Thomas Maclear, the Astronomer Royal at the Cape of Good Hope and the members of the two families became close friends. During this time, he also witnessed the Great Eruption of Eta Carinae (December, 1837).

In addition to his astronomical work, however, this voyage to a far corner of the British empire also gave Herschel an escape from the pressures under which he found himself in London, where he was one of the most sought-after of all British men of science. While in southern Africa, he engaged in a broad variety of scientific pursuits free from a sense of strong obligations to a larger scientific community. It was, he later recalled, probably the happiest time in his life.

In an extraordinary departure from astronomy, Herschel combined his talents with those of his wife, Margaret, and between 1834 and 1838 they produced 131 botanical illustrations of fine quality, showing the Cape flora. Herschel used a camera lucida to obtain accurate outlines of the specimens and left the details to his wife. Even though their portfolio had been intended as a personal record, and despite the lack of floral dissections in the paintings, their accurate rendition makes them more valuable than many contemporary collections. Some 112 of the 132 known flower studies were collected and published as Flora Herscheliana in 1996.

As their home during their stay in the Cape, the Herschels had selected 'Feldhausen' ("Field Houses"), an old estate on the south-eastern side of Table Mountain. Here John set up his reflector to begin his survey of the southern skies.

Herschel, at the same time, read widely. Intrigued by the ideas of gradual formation of landscapes set out in Charles Lyell's Principles of Geology, he wrote to Lyell on 20 February 1836 praising the book as a work that would bring "a complete revolution in [its] subject, by altering entirely the point of view in which it must thenceforward be contemplated" and opening a way for bold speculation on "that mystery of mysteries, the replacement of extinct species by others." Herschel himself thought catastrophic extinction and renewal "an inadequate conception of the Creator" and by analogy with other intermediate causes, "the origination of fresh species, could it ever come under our cognizance, would be found to be a natural in contradistinction to a miraculous process". [15] [16] He prefaced his words with the couplet:

He that on such quest would go must know not fear or failing
To coward soul or faithless heart the search were unavailing.

Taking a gradualist view of development and referring to evolutionary descent from a proto-language, Herschel commented:

Words are to the Anthropologist what rolled pebbles are to the Geologist – battered relics of past ages often containing within them indelible records capable of intelligent interpretation – and when we see what amount of change 2000 years has been able to produce in the languages of Greece & Italy or 1000 in those of Germany France & Spain we naturally begin to ask how long a period must have lapsed since the Chinese, the Hebrew, the Delaware & the Malesass [Malagasy] had a point in common with the German & Italian & each other – Time! Time! Time! – we must not impugn the Scripture Chronology, but we must interpret it in accordance with whatever shall appear on fair enquiry to be the truth for there cannot be two truths. And really there is scope enough: for the lives of the Patriarchs may as reasonably be extended to 5000 or 50000 years apiece as the days of Creation to as many thousand millions of years. [17] [18]

The document was circulated, and Charles Babbage incorporated extracts in his ninth and unofficial Bridgewater Treatise , which postulated laws set up by a divine programmer. [15] When HMS Beagle called at Cape Town, Captain Robert FitzRoy and the young naturalist Charles Darwin visited Herschel on 3 June 1836. Later on, Darwin would be influenced by Herschel's writings in developing his theory advanced in The Origin of Species . In the opening lines of that work, Darwin writes that his intent is "to throw some light on the origin of species – that mystery of mysteries, as it has been called by one of our greatest philosophers," referring to Herschel. However, Herschel ultimately rejected the theory of natural selection. [19]

Herschel returned to England in 1838, was created a baronet, of Slough in the County of Buckingham, [2] and published Results of Astronomical Observations made at the Cape of Good Hope in 1847. In this publication he proposed the names still used today for the seven then-known satellites of Saturn: Mimas, Enceladus, Tethys, Dione, Rhea, Titan, and Iapetus. [20] In the same year, Herschel received his second Copley Medal from the Royal Society for this work. A few years later, in 1852, he proposed the names still used today for the four then-known satellites of Uranus: Ariel, Umbriel, Titania, and Oberon.


Herschel's first glass-plate photograph, dated 9 September 1839, showing the 40-foot telescope Herschel first picture on glass 1839 3.jpg
Herschel's first glass-plate photograph, dated 9 September 1839, showing the 40-foot telescope

Herschel made numerous important contributions to photography. He made improvements in photographic processes, particularly in inventing the cyanotype [22] process, which became known as blueprints. [3] [4] [5] and variations, such as the chrysotype. In 1839, he made a photograph on glass, which still exists, and experimented with some color reproduction, noting that rays of different parts of the spectrum tended to impart their own color to a photographic paper. Herschel made experiments using photosensitive emulsions of vegetable juices, called phytotypes, also known as anthotypes, and published his discoveries in the Philosophical Transactions of the Royal Society of London in 1842. [23] He collaborated in the early 1840s with Henry Collen, portrait painter to Queen Victoria. Herschel originally discovered the platinum process on the basis of the light sensitivity of platinum salts, later developed by William Willis. [24]

Herschel coined the term photography in 1839. [25] [26] Herschel was also the first to apply the terms negative and positive to photography. [2]

Herschel discovered sodium thiosulfate to be a solvent of silver halides in 1819, [27] and informed Talbot and Daguerre of his discovery that this "hyposulphite of soda" ("hypo") could be used as a photographic fixer, to "fix" pictures and make them permanent, after experimentally applying it thus in early 1839.

Herschel's ground-breaking research on the subject was read at the Royal Society in London in March 1839 and January 1840.

Other aspects of Herschel's career

Portrait of John Herschel Herschel sitzend.jpg
Portrait of John Herschel
1867 photograph by Julia Margaret Cameron Julia Margaret Cameron - John Herschel (Metropolitan Museum of Art copy, restored) levels.jpg
1867 photograph by Julia Margaret Cameron

Herschel wrote many papers and articles, including entries on meteorology, physical geography and the telescope for the eighth edition of the Encyclopædia Britannica . [2] He also translated the Iliad of Homer.

In 1823, Herschel published his findings on the optical spectra of metal salts. [28]

Herschel invented the actinometer in 1825 to measure the direct heating power of the sun's rays, [29] and his work with the instrument is of great importance in the early history of photochemistry.

Herschel proposed a correction to the Gregorian calendar, making years that are multiples of 4000 not leap years, thus reducing the average length of the calendar year from 365.2425 days to 365.24225. [30] Although this is closer to the mean tropical year of 365.24219 days, his proposal has never been adopted because the Gregorian calendar is based on the mean time between vernal equinoxes (currently 365.242374 days). [31]

Herschel was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1832, [32] and in 1836, a foreign member of the Royal Swedish Academy of Sciences.

In 1835, the New York Sun newspaper wrote a series of satiric articles that came to be known as the Great Moon Hoax, with statements falsely attributed to Herschel about his supposed discoveries of animals living on the Moon, including batlike winged humanoids.

The village of Herschel in western Saskatchewan Canada, Mount Herschel Antarctica, the crater J. Herschel on the Moon, and the Herschel Girls' School in Cape Town South Africa, are all named after him.

While it is commonly accepted that Herschel Island, in the Arctic Ocean, part of the Yukon Territory, was named after him, the entries in the expedition journal of Sir John Franklin state that the latter wished to honour the Herschel family, of which John Herschel's father, Sir William Herschel, and his aunt, Caroline Herschel, are as notable as John. [33]


Margaret Brodie Stewart by Alfred Edward Chalon 1829 Margaret Herschel00.jpg
Margaret Brodie Stewart by Alfred Edward Chalon 1829
John Frederick William Herschel by Alfred Edward Chalon 1829 John Herschel00.jpg
John Frederick William Herschel by Alfred Edward Chalon 1829

Herschel married his cousin Margaret Brodie Stewart (1810–1884) on 3 March 1829 [34] at Edinburgh and was father of the following children:

  1. Caroline Emilia Elizabeth Herschel (31 March 1830 – 29 Jan 1909), who married Alexander Hamilton-Gordon
  2. Isabella Herschel (5 June 1831 – 1893)
  3. Sir William James Herschel, 2nd Bt. (9 January 1833 – 1917),
  4. Margaret Louisa Herschel (1834–1861), an accomplished artist
  5. Prof. Alexander Stewart Herschel (1836–1907), FRS, FRAS
  6. Col. John Herschel FRS, FRAS, (1837–1921) surveyor
  7. Marie Sophie Herschel (1839–1929)
  8. Amelia Herschel (1841–1926) married Sir Thomas Francis Wade, diplomat and sinologist
  9. Julia Edith Herschel (1842–1933) married on 4 June 1878 to Captain (later Admiral) John Fiot Lee Pearse Maclear
  10. Matilda Rose Herschel (1844–1914), a gifted artist, married William Waterfield (Indian Civil Service)
  11. Francisca Herschel (1846–1932)
  12. Constance Ann Herschel (1855–20 June 1939)


Tombs of John Herschel and Charles Darwin. Westminster Abbey. Herschel&darwin.jpg
Tombs of John Herschel and Charles Darwin. Westminster Abbey.

Herschel died on 11 May 1871 at age 79 at Collingwood, his home near Hawkhurst in Kent. On his death, he was given a national funeral and buried in Westminster Abbey. [34] His obituary by Henry W Field of London was read to the American Philosophical Society on 1 December 1871. [35]


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  1. "Herschel". Random House Webster's Unabridged Dictionary .
  2. 1 2 3 4 5 6 7 8 9 10 11 "Herschel, Sir John Frederick William, 1792–1871, astronomer". NAHSTE project. University of Edinburgh. Archived from the original on 10 May 2007.
  3. 1 2 Go, F. E. (1970). "Blueprint". Encyclopædia Britannica. 3 (Expo'70 ed.). Chicago: William Benton. p. 816.
  4. 1 2 Bridgwater, William; Sherwood, Elizabeth J., eds. (1950). "blueprint". The Columbia Encyclopedia in One Volume (2nd ed.). New York City: Columbia University Press. p. 214.
  5. 1 2 Rosenthal, Richard T. (2000). "The Cyanotype". Vernacular Photography. Archived from the original on 30 March 2013. Retrieved 19 June 2018.
  6. Cobb 2012, pp. 409–439.
  7. "Herschel, John Frederick William (HRSL808JF)". A Cambridge Alumni Database. University of Cambridge.
  8. Wikisource-logo.svg Chisholm, Hugh, ed. (1911). "Herschel, Sir John Frederick William"  . Encyclopædia Britannica (11th ed.). Cambridge University Press.
  9. Elliott, David. "Past RAS Presidents". Royal Astronomical Society. Retrieved 2017-11-20.
  10. Dreyer & Turner 2014, p. 250.
  11. Darwin 1958, pp.  67–68.
  12. Browne 1995, pp. 128, 133.
  13. Darwin 1985a, Letter No. 94.
  14. Berkowitz, Lee. "Contact Lens Timeline". Retrieved 2017-11-19.
  15. 1 2 van Wyhe 2007, p. 197.
  16. Babbage 1838, pp. 225–227.
  17. Desmond & Moore 1991, pp. 214–215.
  18. Darwin 1985b, Letter No. 346.
  19. John Herschel, Physical Geography (1861), p. 12.
  20. Lassell 1848.
  21. Evans 1970, p. 84.
  22. Herschel, John (1901). "General View of Niagara Falls from Bridge". World Digital Library. Detroit Publishing Company. Retrieved 2017-11-20 via Library of Congress.
  23. Herschel 1842, pp. 182–214.
  24. "William Willis". Royal Dutch Academy of Science ( Archived from the original on 2004-12-25.
  25. Schaaf 1979, pp. 47–60.
  26. Peres 2008.
  27. Herschel 1819.
  28. Herschel, J.F.W. (1823). "On the absorption of light by coloured media, and on the colours of the prismatic spectrum exhibited by certain flames; with an account of a ready mode of determining the absolute dispersive power of any medium, by direct experiment". Transactions of the Royal Society of Edinburgh. 9: 445–460.
  29. Anon 1884, p. 527.
  30. Herschel 1876, p. 712.
  31. Steel 2000, p. 185.
  32. "Book of Members, 1780–2010: Chapter H" (PDF). American Academy of Arts and Sciences. Retrieved 15 September 2016.
  33. Burn 2009, pp. 317–323.
  34. 1 2 Crowe, Michael J. "Herschel, Sir John Frederick William, first baronet (1792–1871)". Oxford Dictionary of National Biography (online ed.). Oxford University Press. doi:10.1093/ref:odnb/13101.(Subscription or UK public library membership required.)
  35. Field 1871, pp. 217–223.

Works cited

Further reading

Government offices
Preceded by
Richard Lalor Sheil
Master of the Mint
Succeeded by
Thomas Graham
Baronetage of the United Kingdom
New creation Baronet
(of Slough)
Succeeded by
William James Herschel