John Frederick William Herschel - Biography
Sir John Frederick William Herschel (1792 – 1871), the son of astronomer Sir Frederick Wilhelm Herschel, was a famous British astronomer himself, as well as a mathematician, chemist, biologist and photographer. Best known for ushering in the use of the Julian Day system in astronomy, he also named four of Uranus’ moons, and seven of Saturn’s. Herschel also made contributions to biology, the science of photography, investigated color blindness, and the chemical power of ultraviolet rays.
Born in Slough, Berkshire, Herschel studied at St. John’s and Eton College, at Cambridge University, graduating in 1813 as a Senior Wrangler. During this time, Herschel founded the Analytic Society, with fellow undergraduates, Charles Babbage and George Peacock, which aimed to introduce Continental mathematical theory to English universities. Peacock and Herschel also translated Sylvestre François Lacroix’s Traité du calcul différentiel et du calcul integral. After graduating, Herschel became the first Smith’s prizeman and was elected as a fellow of St. John’s College. In the same year, Herschel was made a fellow at the Royal Society of London, in virtue of the publication of his mathematical paper On a remarkable application of Cotes’s Theorem in the Transactions of the Royal Society. In 1821, his contribution was further recognized by the Royal Society, which awarded him with his first Copley Medal. Herschel’s work on mathematics continued into the 1820’s, culminating in the publication of a two-volume book on the application of finite difference. Although, Herschel largely ceased explicit work on mathematics after the 1820’s, its influence remained clear throughout his life’s work. In 1816, after having taken up astronomy, Herschel built a reflecting telescope with a 6 meter focal length, and a mirror 18 inches in diameter. From Herschel’s letters we can conclude that at least part of his motivation to begin work in astronomy was the fact that there was none to continue the work of his father, who was then 78 years of age. With James South, Herschel examined the double stars catalogued by his father, in the years between 1821 – 1823. In 1820 Herschel was involved in the founding of the Astronomical Society, of which he was named vice-president. In 1926 the Royal Astronomical Society, awarded him their Gold Medal for his work. Herschel would again win this award in 1836. The same work also brought him an award from the French Academy of Sciences, in 1825. In 1831, the Royal Guelphic Order made Herschel a Knight.
As part of Dyonisus Lardner’s Cabinet Cyclopedia, Herschel published his A Preliminary Discourse on the Study of Natural Philosophy, in 1831, which set out a methodology for scientific investigation. The method called for an orderly and balanced relationship between observation and theorizing. Part of Herschel's thesis was the claim that nature was governed by laws difficult to articulate and discern mathematically, and that consequently, the aim of natural philosophy was to come to understand these laws through inductive reasoning. Herchel never veered from his claim that there is a single unifying explanation to all natural phenomena. This thesis assumed a powerful influence, and became an authoritative statement for scientists, especially for those associated with Cambridge University. By the early 1830’s Herschel had become one of the most sought-after scientists in England. Charles Darwin, a student at Cambridge University, proclaimed that Herschel’s thesis inspired ‘a burning zeal’ in him, to continue Herschel’s work.
In 1864, Herschel published a work, which compiled his and his father’s work on astrology, entitled General Catalogue of Nebulae and Clusters - Herschel’s father’s book was entitled Catalogue of Nebulae. After his death, a further complimentary volume was published as General Catalogue of 10,300 Multiple and Double Stars. Much of Herschel’s work in astrology involved double stars, that is, the measurement of the parallax of stars; this was largely a continuation of his father’s work. Herschel also attempted to develop methods for tracking and measuring the orbits of such stars, namely, their orbit around a common gravitational center.
In late 1833, Herschel and his wife, Margaret, traveled to South Africa, with the aim of cataloguing the stars, nebulae, and other astronomical objects in the southern skies. The project was intended to be a continuation and completion of both his and father’s work on the northern skies. Once in Cape Town, South Africa, Herschel constructed a private seven-meter telescope for his observations. During his time in South Africa, Herschel collaborated with and befriended Thomas Maclear, the Astronomer Royal at the Cape of Good Hope.
While in South Africa, Herschel pursued a variety of scientific interests, including botany. Together with his wife, Herschel produced 131 botanical illustrations, of exemplary quality, between 1834-1838. Although intended as a private collection, the botanical studies were later published as ‘Flora Herscheliana’ (1996).
Herschel was inspired by Charles Lyell’s ideas on landscape formation, articulated in Principles of Geology. In a letter written to Lyell, in 1836, Herschel praised Lyell’s work, claiming that it would bring forth a revolution in the subject, by completely changing the methodology and perspective from which it is studied. Herschel also believed that Lyell’s work on landscape formation would help explain the mystery of mysteries, namely, life, and the replacement of extinct species by new ones. In short, Herschel opposed creationism as an explanation of the origin of life, more precisely, Herchel disagreed with the ideas of both catastrophic extinction and renewal. That is, if the origin and development of species could ever come under our understanding it would do so only with an account of natural as opposed to miraculous processes.
Herchel found an analogy between the anthropology of language, and geology and biology, claiming that in considering the developmental process of language exposed by anthropology, that is, of language progressing from very simple and crude forms in the ancient world to the nineteenth century, revealed the natural and procedural development form simple to complex forms. He proposed that a similar process is the cause of then modern landscapes and biological diversity. Moreover, he claimed that in virtue of this hypothesis the biblical account of the world’s age must be abandoned and substituted with a history extending to many thousands of millions of years.
The thoughts of Herschel on evolution were incorporated by Charles Babbage, whom he met while at Cambridge University, into his Bridgewater Treatise. While Herschel’s work on double stars and their movements around a common gravitational center was taken up by Friedrich Bessel, who became the first man to demonstrate the parallax of stars, in 1840. Charles Darwin was also heavily influenced by Herschel, so much so, that when Charles Darwin, aboard the HMS Beagle captained by Robert Fitzroy, docked in Cape Town, in 1836, both Charles Darwin and Fitzroy demanded to visit Herschel. Darwin’s Origin of Species, was heavily influenced by Herschel, as evidenced from the work’s opening page where Darwin writes that the intent of his work 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”, obviously referring to Herschel.
Upon Herschel’s return to England, in 1838, he published Results of Astronomical Observations made at Cape of Good Hope (1847). Especially notable in the work is the recording and naming of seven of Saturn’s moon, Herschel’s names for which are still used today, namely, Titan, Rhea, Dione, Iapetus, Tethys Mimas, and Enceladus. In the year of the works publication, Herschel again received the Copley Medal, from the Royal Society. Five years later, in 1852, Herschel proposed the names of four of Uranus’ moons, which are still used today, namely, Titania, Umbriel, Ariel and Oberon.
Herschel also invented the actinometer, in 1825; an instrument which measures the direct heating power of the sun’s rays. His invention of, and work with the instrument was of great importance in photochemistry’s early history. Herschel also wrote numerous papers and articles for the eight edition of the Encyclopedia Britannica, and translated Homer’s Iliad. Lastly, Herschel also proposed corrections to the Gregorian calendar, which were, however, never adopted.
Numerous physical entities have been named after Herschel, including Herschel Island in the Arctic Ocean, Mount Herschel in Antarctica, and a crater on the moon, as has a girls school in Cape Town, South Africa.