Background
John Herschel was born on March 7, 1792 in Slough, United Kingdom. He was the son of Mary Baldwin and William Herschel. He was the nephew of astronomer Caroline Herschel.
1846
Drawing of John Herschel
1829
John Frederick William Herschel by Alfred Edward Chalon
John Herschel, detail of pencil drawing by H.W. Pickersgill
1825
Henry Collen: self-portrait, miniature painting
1829
Margaret Brodie Stewart by Alfred Edward Chalon
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Astronomer chemist inventor mathematician experimental photographer
John Herschel was born on March 7, 1792 in Slough, United Kingdom. He was the son of Mary Baldwin and William Herschel. He was the nephew of astronomer Caroline Herschel.
John Herschel studied shortly at Eton College and St John's College, Cambridge, graduating as Senior Wrangler in 1813. It was during his time as an undergraduate that he became friends with the mathematicians Charles Babbage and George Peacock.
John Herschel 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.
John 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.
John 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.
John Herschel made numerous important contributions to photography. He made improvements in photographic processes, particularly in inventing the cyanotype process, which became known as blueprint 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. John 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. He collaborated in the early 1840s with Henry Collen, portrait painter to Queen Victoria. John Herschel originally discovered the platinum process on the basis of the light sensitivity of platinum salts, later developed by William Willis. He coined the term photography in 1839. He was also the first to apply the terms negative and positive to photography.
John 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.
For his work with his father, he was presented with the Gold Medal of the Royal Astronomical Society in 1826, 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. John Herschel was made a Knight of the Royal Guelphic Order in 1831.
Discoveries of John Herschel include the galaxies NGC 7, NGC 10, NGC 25, and NGC 28.
John Herschel wrote many papers and articles, including entries on meteorology, physical geography and the telescope for the eighth edition of the Encyclopædia Britannica. He also translated the Iliad of Homer.
John Herschel invented the actinometer in 1825 to measure the direct heating power of the sun's rays, and his work with the instrument is of great importance in the early history of photochemistry.
John Herschel was one of the founders of the Royal Astronomical Society in 1820. He served as President of the Royal Astronomical Society three times: 1827-1829, 1839-1841 and 1847-1849. He was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1832, and in 1836, a foreign member of the Royal Swedish Academy of Sciences.
John Herschel married his cousin Margaret Brodie Stewart (1810-1884) on 3 March 1829 at Edinburgh.
Henry Collen (9 October 1797, Middlesex - 8 May 1879, Brighton) was an English miniature portrait painter to Queen Victoria of the United Kingdom and the Duchess of Kent.
(31 March 1830 - 29 January 1909), married Alexander Hamilton-Gordon
(5 June 1831 - 1893)
Sir William James Herschel, 2nd Baronet (9 January 1833 - 24 October 1917) was a British ICS officer in India who used fingerprints for identification on contracts.
(1834-1861)
Professor Alexander Stewart Herschel (5 February 1836 - 18 June 1907) was a British astronomer.
Colonel John Herschel FRS, FRAS (29 October 1837 - 31 May 1921) was an English military engineer, surveyor and astronomer.
(1839-1929)
(1841-1926), married Sir Thomas Francis Wade, diplomat and sinologist
(1842-1933) married on 4 June 1878 to Captain (later Admiral) John Fiot Lee Pearse Maclear
(1844-1914), married William Waterfield (Indian Civil Service)
(1846-1932)
(1855-20 June 1939)
George Peacock (9 April 1791 - 8 November 1858) was an English mathematician.
