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John Tyndall

John Tyndall (2 August 1820 – 4 December 1893) was a prominent 19th-century Irish physicist. His scientific fame arose in the 1850s from his study of diamagnetism. Later he made discoveries in the realms of infrared radiation and the physical properties of air, proving the connection between atmospheric CO$2$ and what is now known as the greenhouse effect in 1859.

Tyndall also published more than a dozen science books which brought state-of-the-art 19th century experimental physics to a wide audience. From 1853 to 1887 he was professor of physics at the Royal Institution of Great Britain in London. He was elected as a member to the American Philosophical Society in 1868.

Early years and education
Tyndall was born in Leighlinbridge, County Carlow, Ireland. His father was a local police constable, descended from Gloucestershire emigrants who settled in southeast Ireland around 1670. Tyndall attended the local schools (Ballinabranna Primary School) in County Carlow until his late teens, and was probably an assistant teacher near the end of his time there. Subjects learned at school notably included technical drawing and mathematics with some applications of those subjects to land surveying. He was hired as a draftsman by the Ordnance Survey of Ireland in his late teens in 1839, and moved to work for the Ordnance Survey for Great Britain in 1842. In the decade of the 1840s, a railway-building boom was in progress, and Tyndall's land surveying experience was valuable and in demand by the railway companies. Between 1844 and 1847, he was lucratively employed in railway construction planning. In 1847, Tyndall opted to become a mathematics and surveying teacher at Queenwood College, a boarding school in Hampshire. Recalling this decision later, he wrote: "the desire to grow intellectually did not forsake me; and, when railway work slackened, I accepted in 1847 a post as master in Queenwood College." Another recently arrived young teacher at Queenwood was Edward Frankland, who had previously worked as a chemical laboratory assistant for the British Geological Survey. Frankland and Tyndall became good friends. On the strength of Frankland's prior knowledge, they decided to go to Germany to further their education in science. Among other things, Frankland knew that certain German universities were ahead of any in Britain in experimental chemistry and physics. (British universities were still focused on classics and mathematics and not laboratory science.) The pair moved to Germany in summer 1848 and enrolled at the University of Marburg, attracted by the reputation of Robert Bunsen as a teacher. Tyndall studied under Bunsen for two years. Perhaps more influential for Tyndall at Marburg was Professor Hermann Knoblauch, with whom Tyndall maintained communications by letter for many years afterwards. Tyndall's Marburg dissertation was a mathematical analysis of screw surfaces in 1850 (under Friedrich Ludwig Stegmann). Tyndall stayed in Germany for a further year doing research on magnetism with Knoblauch, including some months' visit at the Berlin laboratory of Knoblauch's main teacher, Heinrich Gustav Magnus. It is clear today that Bunsen and Magnus were among the very best experimental science instructors of the era. Thus, when Tyndall returned to live in England in summer 1851, he probably had as good an education in experimental science as anyone in England.

Early scientific work
Tyndall's early original work in physics was his experiments on magnetism and diamagnetic polarity, on which he worked from 1850 to 1856. His two most influential reports were the first two, co-authored with Knoblauch. One of them was entitled "The magneto-optic properties of crystals, and the relation of magnetism and diamagnetism to molecular arrangement", dated May 1850. The two described an inspired experiment, with an inspired interpretation. These and other magnetic investigations very soon made Tyndall known among the leading scientists of the day. He was elected a Fellow of the Royal Society in 1852. In his search for a suitable research appointment, he was able to ask the longtime editor of the leading German physics journal (Poggendorff) and other prominent men to write testimonials on his behalf. In 1853, he attained the prestigious appointment of Professor of Natural Philosophy (Physics) at the Royal Institution in London, due in no small part to the esteem his work had garnered from Michael Faraday, the leader of magnetic investigations at the Royal Institution. About a decade later Tyndall was appointed the successor to the positions held by Michael Faraday at the Royal Institution on Faraday's retirement.

Alpine mountaineering and glaciology
Tyndall visited the Alps mountains in 1856 for scientific reasons and ended up becoming a pioneering mountain climber. He visited the Alps almost every summer from 1856 onward, was a member of the very first mountain-climbing team to reach the top of the Weisshorn (1861), and led one of the early teams to reach the top of the Matterhorn (1868). His is one of the names associated with the "Golden age of alpinism" — the mid-Victorian years when the more difficult of the Alpine peaks were summited for the first time.

In the Alps, Tyndall studied glaciers, and especially glacier motion. His explanation of glacial flow brought him into dispute with others, particularly James David Forbes. Much of the early scientific work on glacier motion had been done by Forbes, but Forbes at that time did not know of the phenomenon of regelation, which was discovered a little later by Michael Faraday. Regelation played a key role in Tyndall's explanation. Forbes did not see regelation in the same way at all. Complicating their debate, a disagreement arose publicly over who deserved to get investigator credit for what. Articulate friends of Forbes, as well as Forbes himself, thought that Forbes should get the credit for most of the good science, whereas Tyndall thought the credit should be distributed more widely. Tyndall commented: "The idea of semi-fluid motion belongs entirely to Louis Rendu; the proof of the quicker central flow belongs in part to Rendu, but almost wholly to Louis Agassiz and Forbes; the proof of the retardation of the bed belongs to Forbes alone; while the discovery of the locus of the point of maximum motion belongs, I suppose, to me." When Forbes and Tyndall were in the grave, their disagreement was continued by their respective official biographers. Everyone tried to be reasonable, but agreement was not attained. More disappointingly, aspects of glacier motion remained not understood or not proved.

Numerous landforms and geographical features are named for John Tyndall, including Tyndall Glacier in Chile, Tyndall Glacier in Colorado, Tyndall Glacier in Alaska, Mount Tyndall in California, and Mount Tyndall in Tasmania.

Main scientific work
Work on glaciers alerted Tyndall to the research of de Saussure into the heating effect of sunlight, and the concept of Fourier, developed by Pouillet and William Hopkins; that heat from the sun penetrates the atmosphere more easily than "obscure heat" (infrared) "terrestrial radiation" from the warmed Earth, causing what we now call the greenhouse effect. In the spring of 1859, Tyndall began research into how thermal radiation, both visible and obscure, affects different gases and aerosols. He developed differential absorption spectroscopy using the electro-magnetic thermopile devised by Melloni. Tyndall began intensive experiments on 9 May 1859, at first without significant results, then improved the sensitivity of the apparatus and on 18 May wrote in his journal "Experimented all day; the subject is completely in my hands!" On 26 May he gave the Royal Society a note which described his methods, and stated "With the exception of the celebrated memoir of M. Pouillet on Solar Radiation through the atmosphere, nothing, so far as I am aware, has been published on the transmission of radiant heat through gaseous bodies. We know nothing of the effect even of air upon heat radiated from terrestrial sources." On 10 June, he demonstrated the research in a Royal Society lecture, noting that coal gas and ether strongly absorbed (infrared) radiant heat, and his experimental confirmation of the (greenhouse effect) concept; that solar heat crosses an atmosphere, but "when the heat is absorbed by the planet, it is so changed in quality that the rays emanating from the planet cannot get with the same freedom back into space. Thus the atmosphere admits of the entrance of solar heat; but checks its exit, and the result is a tendency to accumulate heat at the surface of the planet."

Tyndall's studies of the action of radiant energy on the constituents of air led him onto several lines of inquiry, and his original research results included the following:
 * Tyndall explained the heat in the Earth's atmosphere in terms of the capacities of the various gases in the air to absorb radiant heat, in the form of infrared radiation. His measuring device, which used thermopile technology, is an early landmark in the history of absorption spectroscopy of gases. He was the first to correctly measure the relative infrared absorptive powers of the gases nitrogen, oxygen, water vapour, carbon dioxide, ozone, methane, and other trace gases and vapours. He concluded that water vapour is the strongest absorber of radiant heat in the atmosphere and is the principal gas controlling air temperature. Absorption by the other gases is not negligible but relatively small. Prior to Tyndall it was widely surmised that the Earth's atmosphere warms the surface in what was later called a greenhouse effect, but he was the first to prove it. The proof was that water vapour strongly absorbed infrared radiation. Three years earlier, in 1856, the American scientist Eunice Newton Foote had announced experiments demonstrating that water vapour and carbon dioxide absorb heat from solar radiation, but she did not differentiate the effects of infrared. Relatedly, Tyndall in 1860 was first to demonstrate and quantify that visually transparent gases are infrared emitters.
 * He devised demonstrations that advanced the question of how radiant heat is absorbed and emitted at the molecular level. He appears to be the first person to have demonstrated experimentally that emission of heat in chemical reactions has its physical origination within the newly created molecules (1864). He produced instructive demonstrations involving the incandescent conversion of infrared into visible light at the molecular level, which he called calorescence (1865), in which he used materials that are transparent to infrared and opaque to visible light or vice versa. He usually referred to infrared as "radiant heat", and sometimes as "ultra-red undulations", as the word "infrared" did not start coming into use until the 1880s. His main reports of the 1860s were republished as a 450-page collection in 1872 under the title Contributions to Molecular Physics in the Domain of Radiant Heat.
 * In the investigations on radiant heat in air it had been necessary to use air from which all traces of floating dust and other particulates had been removed. A very sensitive way to detect particulates is to bathe the air with intense light. The scattering of light by particulate impurities in air and other gases, and in liquids, is known today as the Tyndall Effect or Tyndall Scattering. In studying this scattering during the late 1860s Tyndall was a beneficiary of recent improvements in electric-powered lights. He also had the use of good light concentrators. He developed the nephelometer and similar instruments that show properties of aerosols and colloids through concentrated light beams against a dark background and are based on exploiting the Tyndall Effect. (When combined with microscopes, the result is the ultramicroscope, which was developed later by others).
 * He was the first to observe and report the phenomenon of thermophoresis in aerosols. He spotted it surrounding hot objects while investigating the Tyndall Effect with focused lightbeams in a dark room. He devised a better way to demonstrate it, and then simply reported it (1870), without investigating the physics of it in depth.
 * In radiant-heat experiments that called for much laboratory expertise in the early 1860s, he showed for a variety of readily vaporisable liquids that, molecule for molecule, the vapour form and the liquid form have essentially the same power to absorb radiant heat. (In modern experiments using narrow-band spectra, some small differences are found that Tyndall's equipment was unable to get at; see e.g. absorption spectrum of H2O).
 * He consolidated and enhanced the results of Desains, Forbes, Knoblauch and others demonstrating that the principal properties of visible light can be reproduced for radiant heat – namely reflection, refraction, diffraction, polarisation, depolarisation, double refraction, and rotation in a magnetic field.
 * Using his expertise about radiant heat absorption by gases, he invented a system for measuring the amount of carbon dioxide in a sample of exhaled human breath (1862, 1864). The basics of Tyndall's system is in daily use in hospitals today for monitoring patients under anaesthesia. (See capnometry.)
 * When studying the absorption of radiant heat by ozone, he came up with a demonstration that helped confirm or reaffirm that ozone is an oxygen cluster (1862).

 * In the lab he came up with the following simple way to obtain "optically pure" air, i.e. air that has no visible signs of particulate matter. He built a square wooden box with a couple of glass windows on it. Before closing the box, he coated the inside walls and floor of the box with glycerin, which is a sticky syrup. He found that after a few days' wait the air inside the box was entirely particulate-free when examined with strong light beams through the glass windows. The various floating-matter particulates had all ended up getting stuck to the walls or settling on the sticky floor. Now, in the optically pure air there were no signs of any "germs", i.e. no signs of floating micro-organisms. Tyndall sterilised some meat-broths by simply boiling them, and then compared what happened when he let these meat-broths sit in the optically pure air, and in ordinary air. The broths sitting in the optically pure air remained "sweet" (as he said) to smell and taste after many months of sitting, while the ones in ordinary air started to become putrid after a few days. This demonstration extended Louis Pasteur's earlier demonstrations that the presence of micro-organisms is a precondition for biomass decomposition. However, the next year (1876) Tyndall failed to consistently reproduce the result. Some of his supposedly heat-sterilized broths rotted in the optically pure air. From this Tyndall was led to find viable bacterial spores (endospores) in supposedly heat-sterilized broths. He discovered the broths had been contaminated with dry bacterial spores from hay in the lab. All bacteria are killed by simple boiling, except that bacteria have a spore form that can survive boiling, he correctly contended, citing research by Ferdinand Cohn. Tyndall found a way to eradicate the bacterial spores that came to be known as "Tyndallization". Tyndallization historically was the earliest known effective way to destroy bacterial spores. At the time, it affirmed the "germ theory" against a number of critics whose experimental results had been defective from the same cause. During the mid-1870s Pasteur and Tyndall were in frequent communication.

 * Invented a better fireman's respirator, a hood that filtered smoke and noxious gas from air (1871, 1874).
 * In the late 1860s and early 1870s he wrote an introductory book about sound propagation in air, and was a participant in a large-scale British project to develop a better foghorn. In laboratory demonstrations motivated by foghorn issues, Tyndall established that sound is partially reflected (i.e. partially bounced back like an echo) at the location where an air mass of one temperature meets another air mass of a different temperature; and more generally when a body of air contains two or more air masses of different densities or temperatures, the sound travels poorly because of reflections occurring at the interfaces between the air masses, and very poorly when many such interfaces are present. (He then argued, though inconclusively, that this is the usual main reason why the same distant sound, e.g. foghorn, can be heard stronger or fainter on different days or at different times of day.)

An index of 19th-century scientific research journals has John Tyndall as the author of more than 147 papers in science research journals, with practically all of them dated between 1850 and 1884, which is an average of more than four papers a year over that 35-year period.

In his lectures at the Royal Institution Tyndall put a great value on, and was talented at producing, lively, visible demonstrations of physics concepts. In one lecture, Tyndall demonstrated the propagation of light down through a stream of falling water via total internal reflection of the light. It was referred to as the "light fountain". It is historically significant today because it demonstrates the scientific foundation for modern fibre optic technology. During second half of the 20th century Tyndall was usually credited with being the first to make this demonstration. However, Jean-Daniel Colladon published a report of it in Comptes Rendus in 1842, and there's some suggestive evidence that Tyndall's knowledge of it came ultimately from Colladon and no evidence that Tyndall claimed to have originated it himself.

Molecular physics of radiant heat
Tyndall was an experimenter and laboratory apparatus builder, not an abstract model builder. But in his experiments on radiation and the heat-absorptive power of gases, he had an underlying agenda to understand the physics of molecules. Tyndall said in 1879: "During nine years of labour on the subject of radiation [in the 1860s], heat and light were handled throughout by me, not as ends, but as instruments by the aid of which the mind might perchance lay hold upon the ultimate particles of matter." This agenda is explicit in the title he picked for his 1872 book Contributions to Molecular Physics in the Domain of Radiant Heat. It is present less explicitly in the spirit of his widely read 1863 book Heat Considered as a Mode of Motion. Besides heat he also saw magnetism and sound propagation as reducible to molecular behaviours. Invisible molecular behaviours were the ultimate basis of all physical activity. With this mindset, and his experiments, he outlined an account whereby differing types of molecules have differing absorptions of infrared radiation because their molecular structures give them differing oscillating resonances. He'd gotten into the oscillating resonances idea because he'd seen that any one type of molecule has differing absorptions at differing radiant frequencies, and he was entirely persuaded that the only difference between one frequency and another is the frequency. He'd also seen that the absorption behaviour of molecules is quite different from that of the atoms composing the molecules. For example, the gas nitric oxide (NO) absorbed more than a thousand times more infrared radiation than either nitrogen (N2) or oxygen (O2). He'd also seen in several kinds of experiments that – no matter whether a gas is a weak absorber of broad-spectrum radiant heat – any gas will strongly absorb the radiant heat coming from a separate body of the same type of gas.In the late 1850s Balfour Stewart had showed that cold rock-salt was a very strong absorber of the radiations from hot rock-salt, even though rock-salt was a very weak absorber of the radiations from all other kinds of heat-sources tested. By the early 1860s this had been generalized in the scientific literature to the principle that any kind of chemical will very strongly absorb the radiations coming from a separate body of the same kind of chemical. In Tyndall's words this was a "principle which lies at the basis of spectrum analysis, ... namely, that a body which is competent to emit any ray, whether of heat or light, is competent in the same degree to absorb that ray" (1866). Tyndall made several original observations around 1863 by beginning with the assumption that this principle is correct. The following is a summary of one of them. It was well-known at the time that in a flame of burning carbon monoxide, the carbon monoxide chemically combines with the oxygen of the air to form carbon dioxide plus heat. Tyndall observed that if a body of cold or room-temperature carbon dioxide is placed near the flame "the cold gas is intensely opaque to [i.e. it very strongly absorbs] the radiation from this particular flame, though it is highly transparent to [i.e. it very weakly absorbs] heat of every other kind." Thus the great bulk of the heat in the carbon monoxide flame fits the emission spectrum of carbon dioxide, implying the heat is a radiant emission from the newly formed carbon dioxide molecules. Tyndall got the same type of result with a flame of burning hydrogen, another flame known to be chemically simple in the sense that very little intermediate or transitory molecules are produced in it. This appears to be the first demonstration that the heat given out in chemical reactions has its physical origination within the new molecules. Tyndall's report of the demonstration is in Contributions to Molecular Physics in the Domain of Radiant Heat, sections 11–17 of Chapter VI, dated 1864. A related demonstration is in sections 3–8 of Chapter V, dated 1863. It is also discussed in Tyndall's Fragments of Science, Volume I Chapter III, dated 1866. For a modern analysis of where the heat is coming from in the carbon monoxide flame see Tyndall also interpreted the carbon monoxide flame as showing that carbon dioxide's spectral profile remains the same at room temperature and at a temperature of over 2000 °C, the temperature in the flame; and likewise for the product of the hydrogen flame. This was in contrast to the easily seen fact in solids such as carbon and platinum where the spectral profile moves towards the quicker frequencies when the temperature is increased. That demonstrated a kinship between the molecular mechanisms of absorption and emission. Such a kinship was also in evidence in experiments by Balfour Stewart and others, cited and extended by Tyndall, that showed with respect to broad-spectrum radiant heat that molecules that are weak absorbers are weak emitters and strong absorbers are strong emitters. (For example, rock-salt is an exceptionally poor absorber of heat via radiation, and a good absorber of heat via conduction. When a plate of rock-salt is heated via conduction and let stand on an insulator, it takes an exceptionally long time to cool down; i.e., it's a poor emitter of infrared.) The kinship between absorption and emission was also consistent with some generic or abstract features of resonators. The chemical decomposition of molecules by lightwaves (photochemical effect) convinced Tyndall that the resonator could not be the molecule as a whole unit; it had to be some substructure, because otherwise the photochemical effect would be impossible. But he was without testable ideas as to the form of this substructure, and did not partake in speculation in print. His promotion of the molecular mindset, and his efforts to experimentally expose what molecules are, has been discussed by one historian under the title "John Tyndall, The Rhetorician of Molecularity".

Educator
Besides being a scientist, John Tyndall was a science teacher and evangelist for the cause of science. He spent a significant amount of his time disseminating science to the general public. He gave hundreds of public lectures to non-specialist audiences at the Royal Institution in London. When he went on a public lecture tour in the US in 1872, large crowds of non-scientists paid fees to hear him lecture about the nature of light. A typical statement of Tyndall's reputation at the time is this from a London publication in 1878: "Following the precedent set by Faraday, Professor Tyndall has succeeded not only in original investigation and in teaching science soundly and accurately, but in making it attractive.... When he lectures at the Royal Institution the theatre is crowded." Tyndall said of the occupation of teacher "I do not know a higher, nobler, and more blessed calling." His greatest audience was gained ultimately through his books, most of which were not written for experts or specialists. He published more than a dozen science books. From the mid-1860s on, he was one of the world's most famous living physicists, due firstly to his skill and industry as a tutorialist. Most of his books were translated into German and French with his main tutorials staying in print in those languages for decades.

As an indicator of his teaching attitude, here are his concluding remarks to the reader at the end of a 200-page tutorial book for a "youthful audience", The Forms of Water (1872): "Here, my friend, our labours close. It has been a true pleasure to me to have you at my side so long. In the sweat of our brows we have often reached the heights where our work lay, but you have been steadfast and industrious throughout, using in all possible cases your own muscles instead of relying upon mine. Here and there I have stretched an arm and helped you to a ledge, but the work of climbing has been almost exclusively your own. It is thus that I should like to teach you all things; showing you the way to profitable exertion, but leaving the exertion to you.... Our task seems plain enough, but you and I know how often we have had to wrangle resolutely with the facts to bring out their meaning. The work, however, is now done, and you are master of a fragment of that sure and certain knowledge which is founded on the faithful study of nature.... Here then we part. And should we not meet again, the memory of these days will still unite us. Give me your hand. Good bye."

As another indicator, here is the opening paragraph of his 350-page tutorial entitled Sound (1867): "In the following pages I have tried to render the science of acoustics interesting to all intelligent persons, including those who do not possess any special scientific culture. The subject is treated experimentally throughout, and I have endeavoured so to place each experiment before the reader that he should realise it as an actual operation." In the preface to the 3rd edition of this book, he reports that earlier editions were translated into Chinese at the expense of the Chinese government and translated into German under the supervision of Hermann von Helmholtz (a big name in the science of acoustics). His first published tutorial, which was about glaciers (1860), similarly states: "The work is written with a desire to interest intelligent persons who may not possess any special scientific culture."

His most widely praised tutorial, and probably his biggest seller, was the 550-page "Heat: a Mode of Motion" (1863; updated editions until 1880). It was in print for at least 50 years, and is in print today. Its primary feature is, as James Clerk Maxwell said in 1871, "the doctrines of the science [of heat] are forcibly impressed on the mind by well-chosen illustrative experiments."

Tyndall's three longest tutorials, namely Heat (1863), Sound (1867), and Light (1873), represented state-of-the-art experimental physics at the time they were written. Much of their contents were recent major innovations in the understanding of their respective subjects, which Tyndall was the first writer to present to a wider audience. One caveat is called for about the meaning of "state of the art". The books were devoted to laboratory science and they avoided mathematics. In particular, they contain absolutely no infinitesimal calculus. Mathematical modelling using infinitesimal calculus, especially differential equations, was a component of the state-of-the-art understanding of heat, light and sound at the time.

Demarcation of science from religion

The majority of the progressive and innovative British physicists of Tyndall's generation were conservative and orthodox on matters of religion. That includes for example James Joule, Balfour Stewart, James Clerk Maxwell, George Gabriel Stokes and Lord Kelvin – all names investigating heat or light contemporaneously with Tyndall. These conservatives believed, and sought to strengthen the basis for believing, that religion and science were consistent and harmonious with each other. Tyndall, however, was a member of a club that vocally supported Charles Darwin's theory of evolution and sought to strengthen the barrier, or separation, between religion and science. The most prominent member of this club was the anatomist Thomas Henry Huxley. Tyndall first met Huxley in 1851 and the two had a lifelong friendship. Chemist Edward Frankland and mathematician Thomas Archer Hirst, both of whom Tyndall had known since before going to university in Germany, were members too. Others included the social philosopher Herbert Spencer.

Though not nearly so prominent as Huxley in controversy over philosophical problems, Tyndall played his part in communicating to the educated public what he thought were the virtues of having a clear separation between science (knowledge & rationality) and religion (faith & spirituality). As the elected president of the British Association for the Advancement of Science in 1874, he gave a long keynote speech at the Association's annual meeting held that year in Belfast. The speech gave a favourable account of the history of evolutionary theories, mentioning Darwin's name favourably more than 20 times, and concluded by asserting that religious sentiment should not be permitted to "intrude on the region of knowledge, over which it holds no command". This was a hot topic. The newspapers carried the report of it on their front pages – in Britain, Ireland & North America, even the European Continent – and many critiques of it appeared soon after. The attention and scrutiny increased the friends of the evolutionists' philosophical position, and brought it closer to mainstream ascendancy. The text of Tyndall's 1874 Belfast Address is available at Victorianweb.org. This speech got more coverage in the Victorian-era newspapers than any other single public speech in the decades-long Victorian debate over the status of evolution theory. A lengthy review of the speech and the speech's reception by London newspapers was published by The New York Times on 5 September 1874. It is downloadable. The great majority of London newspapers either endorsed Tyndall's position or took a neutral but respectful attitude towards it. Among other commentators the speech did have critics but a majority of these looked askance at subtleties and minor aspects (e.g.), (e.g.); only a minority defended a role for religious belief in formation of knowledge. As the London Times put it when the speech was making front-page news: "It is probably part of the great change in the manners of this country that [the speech]... will now encounter little contradiction even in the most religious circles" (reprinted by New York Times, 7 Sep 1874). Among the exceptions, the Irish Catholic bishops decried it as paganism. Because the speech got widespread attention and little contradiction, and came from the Establishment post of the presidency of the British Association for the Advancement of Science, later historians have seen the speech as the "final victory" of the evolutionists in Victorian Britain.

In Rome in 1864, Pope Pius IX in his Syllabus of Errors decreed that it was an error that "reason is the ultimate standard by which man can and ought to arrive at knowledge" and an error that "divine revelation is imperfect" in the Bible – and anyone maintaining those errors was to be "anathematized" – and in 1888 decreed as follows: "The fundamental doctrine of rationalism is the supremacy of the human reason, which, refusing due submission to the divine and eternal reason, proclaims its own independence... A doctrine of such character is most hurtful both to individuals and to the State... It follows that it is quite unlawful to demand, to defend, or to grant, unconditional [or promiscuous] freedom of thought, speech, writing, or religion." Those principles and Tyndall's principles were profound enemies. Luckily for Tyndall he didn't need to get into a contest with them in Britain. Even in Italy, Huxley and Darwin were awarded honorary medals and most of the Italian governing class was hostile to the papacy. But in Ireland during Tyndall's lifetime the majority of the population grew increasingly doctrinaire and vigorous in its Roman Catholicism and also grew stronger politically. Between 1886 and 1893, Tyndall was active in the debate in England about whether to give the Catholics of Ireland more freedom to go their own way. Like the great majority of Irish-born scientists of the 19th century he opposed the Irish Home Rule Movement. He had ardent views about it, which were published in newspapers and pamphlets. For example, in an opinion piece in The Times on 27 December 1890 he saw priests and Catholicism as "the heart and soul of this movement" and wrote that placing the non-Catholic minority under the dominion of "the priestly horde" would be "an unspeakable crime". He tried unsuccessfully to get the UK's premier scientific society to denounce the Irish Home Rule proposal as contrary to the interests of science.

In several essays included in his book Fragments of Science for Unscientific People, Tyndall attempted to dissuade people from believing in the potential effectiveness of prayers. At the same time, though, he was not broadly anti-religious.

Many of his readers interpret Tyndall to be a confirmed agnostic,      though he never explicitly declared himself to be so. The following statement from Tyndall is an example of Tyndall's agnostic mindset, made in 1867, and reiterated in 1878: "The phenomena of matter and force come within our intellectual range... but behind, and above, and around us the real mystery of the universe lies unsolved, and, as far as we are concerned, is incapable of solution.... Let us lower our heads, and acknowledge our ignorance, priest and philosopher, one and all."

Private life
Tyndall did not marry until age 55. His bride, Louisa Hamilton, was the 30-year-old daughter of a member of parliament (Lord Claud Hamilton, M.P.). The following year, 1877, they built a summer chalet at Belalp in the Swiss Alps. Before getting married Tyndall had been living for many years in an upstairs apartment at the Royal Institution and continued living there after marriage until 1885 when a move was made to a house near Haslemere 45 miles southwest of London. The marriage was a happy one and without children. He retired from the Royal Institution at age 66 having complaints of ill health.

Tyndall became financially well-off from sales of his popular books and fees from his lectures (but there is no evidence that he owned commercial patents). For many years he got non-trivial payments for being a part-time scientific advisor to a couple of quasi-governmental agencies and partly donated the payments to charity. His successful lecture tour of the United States in 1872 netted him a substantial amount of dollars, all of which he promptly donated to a trustee for fostering science in America. Late in life his money donations went most visibly to the Irish Unionist political cause. When he died, his wealth was £22,122. For comparison's sake, the income of a police constable in London was about £80 per year at the time.

Death
In his last years Tyndall often took chloral hydrate to treat his insomnia. When bedridden and ailing, he died from an accidental overdose of this drug in 1893 at the age of 73, and was buried at Haslemere. The overdose was administered by his wife Louisa. "My darling," said Tyndall when he realized what had happened, "you have killed your John."

Afterwards, Tyndall's wife took possession of his papers and assigned herself supervisor of an official biography of him. She procrastinated on the project, however, and it was still unfinished when she died in 1940 aged 95. The book eventually appeared in 1945, written by A. S. Eve and C. H. Creasey, whom Louisa Tyndall had authorised shortly before her death.

John Tyndall is commemorated by a memorial (the Tyndalldenkmal) erected at an elevation of 2340 m on the mountain slopes above the village of Belalp, where he had his holiday home, and in sight of the Aletsch Glacier, which he had studied.

John Tyndall's books

 * Tyndall, J. (1860), The glaciers of the Alps, Being a narrative of excursions and ascents, an account of the origin and phenomena of glaciers and an exposition of the physical principles to which they are related, (1861 edition) Ticknor and Fields, Boston
 * Tyndall, J. (1862), Mountaineering in 1861. A vacation tour, Longman, Green, Longman, and Roberts, London
 * Tyndall, J. (1865), On Radiation: One Lecture (40 pages)
 * Tyndall, J. (1868), Heat : A mode of motion, (1869 edition) D. Appleton, New York
 * Tyndall, J. (1869), Natural Philosophy in Easy Lessons (180 pages) (a physics book intended for use in secondary schools)
 * Tyndall, J. (1870), Faraday as a discoverer, Longmans, Green, London
 * Tyndall, J. (1870), Three Scientific Addresses by Prof. John Tyndall (75 pages)
 * Tyndall, J. (1870), Notes of a Course of Nine Lectures on Light (80 pages)
 * Tyndall, J. (1870), Notes of a Course of Seven Lectures on Electrical Phenomena and Theories (50 pages)
 * Tyndall, J. (1870), Researches on diamagnetism and magne-crystallic action: including the question of diamagnetic polarity, (a compilation of 1850s research reports), Longmans, Green, London
 * Tyndall, J. (1871), Hours of exercise in the Alps, Longmans, Green, and Co., London
 * Tyndall, J. (1871), Fragments of Science: A Series of Detached Essays, Lectures, and Reviews, (1872 edition), Longmans, Green, London
 * Tyndall, J. (1872), Contributions to Molecular Physics in the Domain of Radiant Heat, (a compilation of 1860s research reports), (1873 edition), D. Appleton and Company, New York
 * Tyndall, J. (1873), The forms of water in clouds & rivers, ice & glaciers, H. S. King & Co., London
 * Tyndall, J. (1873), Six Lectures on Light (290 pages)
 * Tyndall, J. (1876), Lessons in Electricity at the Royal Institution (100 pages), (intended for secondary school students)
 * Tyndall, J. (1878), Sound; delivered in eight lectures, (1969 edition), Greenwood Press, New York
 * Tyndall, J. (1882), Essays on the floating matter of the air, in relation to putrefaction and infection, D. Appleton, New York
 * Tyndall, J. (1887), Light and electricity: notes of two courses of lectures before the Royal Institution of Great Britain, D. Appleton and Company, New York
 * Tyndall, J. (1892), New Fragments (miscellaneous essays for a broad audience), D. Appleton, New York

Biographies of John Tyndall

 * 430 pages. This is the "official" biography.
 * William Tulloch Jeans wrote a 100-page biography of Professor Tyndall in 1887 (the year Tyndall retired from the Royal Institution). Downloadable.
 * Louisa Charlotte Tyndall, his wife, wrote an 8-page biography of John Tyndall that was published in 1899 in Dictionary of National Biography (volume 57). It is readable online (and a 1903 republication of the same biography is also readable online).
 * Edward Frankland, a longtime friend, wrote a 16-page biography of John Tyndall as an obituary in 1894 in a scientific journal. It is readable online.
 * Gives an account of Tyndall's vocational development prior to 1853.
 * 220 pages.
 * Arthur Whitmore Smith, a professor of physics, wrote a 10-page biography of John Tyndall in 1920 in a scientific monthly. Readable online.
 * John Walter Gregory, a naturalist, wrote a 9-page obituary of John Tyndall in 1894 in a natural science journal. Readable online.
 * An early, 8-page profile of John Tyndall appeared in 1864 in Portraits of Men of Eminence in Literature, Science and Art, Volume II, pages 25–32.
 * A brief profile of Tyndall based on information supplied by Tyndall himself appeared in 1874 in.
 * Claud Schuster, John Tyndall as a Mountaineer, 56-page essay included in Schuster's book Postscript to Adventure, year 1950 (New Alpine Library: Eyre & Spottiswoode, London).
 * The first major biography of Tyndall since 1945.
 * The first major biography of Tyndall since 1945.
 * The first major biography of Tyndall since 1945.

title: John Tyndall


text:
Talk:Gaia philosophy/Archive 1

quote The more political followers sometimes call themselves Gaians and actively seek to restore the Earth's homeostasis - whenever they see it out of balance, e.g. to prevent manmade climate change, primate extinction, or rainforest loss. In effect, they seek to cooperate to 'become' the "system conciously manipulating to make conditions more conducive to life." Such activity 'defines' the homeostasis. end of quote

Do Gaians seek to cooperate to 'become' the system or do they seek to be 'part' of the system ??? Is that coherent ?

---

slowly the tangle of messy politics and sciences starts to make sense... slowly... I am wondering if it's worth mentioning Goldsmith and his "Gaian hierarchy"... he's the best example of these "political Gaians committed to acting as a keystone species". A lot of people think he's a fascist...

- I just don't buy that the confusion about the spectrum is because Gaia theory is "new" - it's quite ancient. The confusion is because the science of testing the homeostasis and the politics of becoming a part of the homeostatic balance are inseparable - science doesn't actually apply to it.

Imagine you are running a science experiment in the garden and as a political priority I am entering your garden and changing the results. I look like a villain.

Now imagine that the garden is the whole planet, and you are testing whether it is alive by killing it - and seeing if we die with it - if we don't, it's "life" wasn't essential to ours. Again, as a political priority I am altering the way you and your allies deal with the garden - and now I look like a hero.

The Precautionary Principle actually alters the concept of what science *is* - puts really important limits on experiment - that's the source of confusion.

(comments from 67.193.54.xxx which were originally on the article page)

March 31, 2002

The silent side of human is often ignored. Does that make it unreal ? No. Racial merories are often called conjecture, theory, yet they exist. Not viewable or percieve-able externally, with eyes, ears, noses etc, they are found within.

What makes us judge another, what makes one say some such as "I like him or her", I don't like him or her" ?

I don't know why. Yet we do it. It is when this viewing of anothers writing or other expressions is turned within, towards ones self, that one can find racial memories that go back to the dawns of life on Earth. And beyond.

These lives at the dawns of life on Earth did not have hands and feet and mouths to speak with, yet as we are they were also of The Mother and The Father, terms of respect that is due.

The Mother and The Father are not theories, they are facts. Gaia is not a theory, she is a fact. Are we but one form of life independent ? or are we interdependent with all life forms on Earth, part of a greater life unlike any of her parts ? Or are we both ? Call her Gaia, call her The Mother, call her Earth, she is a fact.

I hope it is seen that this addition is in offering of inner and greater definition and so not deemed inapropriate the encyclopedia.

Gaia is a fact.

 * it's fine to put such comment here, in "talk". But what you are talking about is some kind of "Gaian cosmology"  <-- click both terms to see the separate definitions.  For it to be a "fact" to the satisfaction of the Karl Popper clones here, you would have to destroy Gaia and see if you survived.  Their MAD view of the universe is under debate in talk:particle physics.  What can we agree on?  Well, maybe the idea of a foundation ontology, but maybe not, as some of them seem willing to sabotage or delete articles that try to build bridges betwen world-views.

 * To be clear, I (Nate Silva) moved someone else's comments which were inappropriately in the article, to this talk page. I certainly don't endorse the comments! (It appears the poster has tried to re-insert his/her comments and someone else has removed them again. If it happens again it should probably go to vandalism in progress.)

Hum...maybe we could find a better example than that wind

Ant

-

>A simple example is large trees having the effect of reducing wind energy, alowing organisms to live underneath the canopy; there's an inverse relation between the amount of light an organism receives as against the degree to which it must absorb wind energy for the system. (I forget the paper where I read this forest example - I don't think it was Lovelock who said it though. Needs checking)

Well, I didnot find who said that. And I am puzzled by the point about the inverse relation between amount of light and capacity to absorb the wind energy. I find that not very clear.

To illustrate the <> point, I think the relationship between trees and pteridophytes is very obvious. Large trees have for example the effect of limiting direct sun light and on trapping humidity. This create a very favorable microclimate for organisms such as ferns. First because they rather thrive in shadowy light. Second because their reproductive cycle is highly dependant on water (sexual reproduction is achieved through the liberation of swimming gametophytes).

To rather illustrate the <> point, I think the lichens symbiosis and ecological impact is a great example. Lichens have a dual nature. They are a symbiosis between fungus and algae. Algea is the photosynthetic organism, and provides metabolites to the fungus. The latter offers shelter to the algae (protection against the wind and direct sunlight) and provides water, CO2, minerals and some organic molecules. Lichens are exceptional pioneers, able to grow on sand, rock, lava...They are in particular a key species in the artic ecosystem, where they form a deep layer regulating soil temperature and humidity, hosting and providing food to many species. By incrustration in the substrate and through acid liberation, they desintegrate rocks and contribute over time to pedogenesis, thus opening the way to a dynamic colonization by moss, ferns and later superior plants.

Just to clarify things, I think I stand in the middle of that spectrum of hypotheses. However, I support the fact that life characteristics are changing over time, through changes in a whole species (favored by a climatologic/pedologic/atmospheric situation) rather than through one individual in a species. Upon long-span times, waves of extinction, emergence of new groups, success of some of them and potential extinction again. That point of view supports the conservation of life, but not so much the conservation of a specific life/organism. It agrees with the conservation of conditions for life support, but maybe not the conservation of the same conditions. I do not know how to express it very well, but I guess that is probably more about evolution than what I see as potential stagnation.

I wonder what really defines the biosphere to be off-balance... I see off-balance as a point where the planet is badly heading toward conditions improper to life, thus leading to her death. But I think many people support the idea that off-balance is when heading toward conditions where actual life/species (part of it) are losing support (ie, extinction of some species).

 * did you read the Gaia Theory proper? damn this naming non-convention - the Theory holds (unlike the small-t theory which is the field itself) that the balances are homeorhetic, like technical ceilings and floors in the stock market.  That doesn't necessrily mean "death" for Earth but it might wipe out the dominant species on the top of the food chain and many others.  It would certainly drastically cut back on the ability to support human life since all our culture and infrastructure is designed for climate conditions more or less as they are.  Extinction is a normal part of Gaia just like cell death, but accelerating it by concious effort (or failures of restraint by dominant species who will go nameless here) certainly can lead to 'conditions improper to life' in that broad sense above.  To actually wipe out Gaia the biosphere you'd have to replace the cyanophytes at the bottom of the food chain, out competing them for light and thus food.  It's happened.  The cyanophytes *got* there by replacing older bacteria that didn't pump out oxygen at all... about a billion years ago when Earth had a methane atmosphere.  THe single-celled shit-critters that ruled Earth then sure got flushed in a hurry... and so might we...

Though I agree the more biodiversity, the better for a good balance.

 * the original Gaia Hypothesis held that the Earth's biosphere may be in homeostasis - but that is impossible to prove, as if it is, then disrupting that balance is critical to our survival, and disrupting it will kill us all. It doesn't have falsifiability since the experiment is outside any feasible method, and certainly outside any reasonable method.  The fantasy thought experiment where we try to disrupt the homeostasis, e.g. by massive global thermonuclear assault, and succeed, and somehow survive in significant numbers, is pretty much the only way to test the Gaia Hypothesis.  Meanwhile, the Hypothesis fuels fantasies that the Earth will always clean up after us like a loving parent - so it is also morally hazardous.  Same with meme hypothesis - which has spawned many more testable "meme theories" and should replace Dawkin's vague concept ASAP to avoid the moral hazard and enable testing.  It's not just BIO diversity which is good for what we think of as well-being - it's also PSYCHO diversity...

The position of one on the "spectrum" is somehow highly related to his role as an observer or as an actor. Highly, but not completely. Many people are only (non-consciously maybe) on the undeniable side, but are putting a lot of energy in trying to level the balance.

Ant

I think I did (though these h, H, t and T ...), but probably I didnot. Neither did I succeed to put in words where I thought differently. Doesn't matter anyway.

>That doesn't necessrily mean "death" for Earth but it might wipe out the dominant species on the top of the food chain and many others. It would certainly drastically cut back on the ability to support human life since all our culture and infrastructure is designed for climate conditions more or less as they are.

However, I understood that both L. and M. said that there were some essential elements that the planet couldnot afford to lose (cyanophytes for example) while other elements were quite secondary (big animals for example). If so, our disappearance wouldnot mean much and our role in the structure is pretty limited. We could be just some temporary animals. And having people believe in that theory (or T, whatever) wouldnot help a lot to make humans act to "push" in the right direction (or at least make them stop pushing in the wrong...). It would just make them realize how little and insignificant they are, just a tiny part of a giant scheme. Do you see what I mean here ? They might get more conscious of the importance of interconnection between all the different elements, of the cooperation that can exist between some uni or pluri organisms... that could give them the idea of entering the global arrangement. But if they are driven to believe in that scheme, and are driven to believe they are mites, how would they feel the importance of their acts ?

>the original Gaia Hypothesis held that the Earth's biosphere may be in homeostasis - but that is impossible to prove

How much does it matter if that might help in the end to restaure a certain peace on the earth ? I mean, I kind of believe in God, as milions of people. Only, there could be as many Gods as they are believers, since we have no proof of its existence. Just as Gaia. Of course we have a nice bunch of people fighting with others on that very subject. I guess they mostly are calling Him for help while doing so, as the kids are sometimes being a pain just as a call for attention. I guess they are waiting for their God to prove his existence by doing so. Still, there are many other believers that live in peace, maybe is there more peace on earth because they believe. And meanwhile, there are also people trying to prove that God is a fact. For those who believe in Gaia and want to use her to "save the earth", the only thing to fear is these people that could dream of proving Gaia existence by trying to wipe it out. The others...why wouldnot they accept it as they are accepting God without any proof ? They are more numerous.

Little Ant

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Talk:Gaia philosophy/Archive 1


text:
Salvador Luria

Salvador Edward Luria (born Salvatore Luria; August 13, 1912 – February 6, 1991) was an Italian microbiologist, later a naturalized U.S. citizen. He won the Nobel Prize in Physiology or Medicine in 1969, with Max Delbrück and Alfred Hershey, for their discoveries on the replication mechanism and the genetic structure of viruses. Salvador Luria also showed that bacterial resistance to viruses (phages) is genetically inherited.

Early life
Luria was born Salvatore Luria in Turin, Italy to an influential Italian Sephardi Jewish family. His parents were Davide and Ester (Sacerdote) Luria. He attended the medical school at the University of Turin studying with Giuseppe Levi. There, he met two other future Nobel laureates: Rita Levi-Montalcini and Renato Dulbecco. He graduated from the University of Turin in 1935 and never got a master's degree or a PhD as they were not contemplated by the Italian high educational system (which, on the other hand, was very selective). From 1936 to 1937, Luria served his required time in the Italian army as a medical officer. He then took classes in radiology at the University of Rome. Here, he was introduced to Max Delbrück's theories on the gene as a molecule and began to formulate methods for testing genetic theory with the bacteriophages, viruses that infect bacteria.

In 1938, he received a fellowship to study in the United States, where he intended to work with Delbrück. Soon after Luria received the award, Benito Mussolini's fascist regime banned Jews from academic research fellowships. Without funding sources for work in the U.S. or Italy, Luria left his home country for Paris, France in 1938. As the Nazi German armies invaded France in 1940, Luria fled on bicycle to Marseille where he received an immigration visa to the United States.

Phage research
Luria arrived in New York City on September 12, 1940, and soon changed his first and middle names. With the help of physicist Enrico Fermi, whom he knew from his time at the University of Rome, Luria received a Rockefeller Foundation fellowship at Columbia University. He soon met Delbrück and Hershey, and they collaborated on experiments at Cold Spring Harbor Laboratory and in Delbrück's lab at Vanderbilt University.

His famous experiment with Delbrück in 1943, known as the Luria–Delbrück experiment, demonstrated statistically that inheritance in bacteria must follow Darwinian rather than Lamarckian principles and that mutant bacteria occurring randomly can still bestow viral resistance without the virus being present. The idea that natural selection affects bacteria has profound consequences, for example, it explains how bacteria develop antibiotic resistance.

Luria and Latarjet in 1947 published a quantitative analysis on the effect of ultraviolet irradiation on bacteriophage multiplication during intracellular growth. During the early course of infection they found an increase in bacteriophage resistance to ultraviolet irradiation and then later a decrease. At the time this pattern, known as the Luria-Laterjet effect, was published little was known about the central role of DNA in biology. Later work established that multiple specific DNA repair pathways, encoded by the infecting bacteriophage, contribute to the increase in UV resistance early in infection.

From 1943 to 1950, he worked at Indiana University. His first graduate student was James D. Watson, who went on to discover the structure of DNA with Francis Crick. In January 1947, Luria became a naturalized citizen of the United States.

In 1950, Luria moved to the University of Illinois Urbana–Champaign. In the early 1950s, Luria and Giuseppe Bertani discovered the phenomenon of host-controlled restriction and modification of a bacterial virus: a culture of E. coli can significantly reduce the production of phages grown in other strains; however, once the phage become established in that strain, they also become restricted in their ability to grow in other strains. It was later discovered by other researchers that bacteria produce enzymes that cut viral DNA at particular sequences but not the bacteria's own DNA, which is protected by methylation. These enzymes became known as restriction enzymes and developed into one of the main molecular tools in molecular biology.

Luria won the Nobel Prize in Physiology or Medicine in 1969, with Max Delbrück and Alfred Hershey, for their discoveries on the replication mechanism and the genetic structure of viruses.

Later work
In 1959, he became chair of Microbiology at the Massachusetts Institute of Technology (MIT). At MIT, he switched his research focus from phages to cell membranes and bacteriocins. While on sabbatical in 1963 to study at the Institut Pasteur in Paris, he found that bacteriocins impair the function of cell membranes. Returning to MIT, his lab discovered that bacteriocins achieve this impairment by forming holes in the cell membrane, allowing ions to flow through and destroy the electrochemical gradient of cells. In 1972, he became chair of The Center for Cancer Research at MIT. The department he established included future Nobel Prize winners David Baltimore, Susumu Tonegawa, Phillip Allen Sharp and H. Robert Horvitz.

In addition to the Nobel Prize, Luria received a number of awards and recognitions. He was elected to the American Academy of Arts and Sciences in 1959. He was named a member of the National Academy of Sciences in 1960. In 1964, he was elected to the American Philosophical Society. From 1968 to 1969, he served as president of the American Society for Microbiology. In 1969, he was awarded the Louisa Gross Horwitz Prize from Columbia University together with Max Delbrück, co-winner with Luria of the Nobel Prize in Physiology or Medicine in 1969. In the U.S. he won the 1974 National Book Award in Science for his popular science book Life: the Unfinished Experiment and received the National Medal of Science in 1991.

Political activism
Throughout his career, Luria was an outspoken political advocate. He joined with Linus Pauling in 1957 to protest against nuclear weapon testing. Luria was an opponent of the Vietnam War and a supporter of organized labor. In the 1970s, he was involved in debates over genetic engineering, advocating a compromise position of moderate oversight and regulation rather than the extremes of a complete ban or full scientific freedom. Due to his political involvement, he was blacklisted from receiving funding from the National Institutes of Health for a short time in 1969.

Noam Chomsky describes him as a friend, and claims that Luria attempted to influence Jewish American writer Elie Wiesel's public stance on Israel.

Death
Luria died in Lexington, Massachusetts of a heart attack on 6 February, 1991 at the age of 78.

title: Salvador Luria


text:
1802 in music

This is a list of music-related events in 1802.

Events

 * January 9 – The Harmonic Society of Philadelphia is founded, with native composer Andrew Law as its president.
 * January 20 – Luigi Boccherini receives a pension from Joseph Bonaparte.
 * February 15 – Muzio Clementi publishes the second volume of his Practical Harmony.
 * March 19 – Composer François-Adrien Boieldieu marries dancer Clotilde Mafleuray.
 * April 30 – Louis Spohr begins his violin studies under Franz Eck.
 * May 5
 * Composer Giovanni Paisiello, recently arrived in Paris, meets his host, Napoleon, for the first time.
 * Composers Jan Ladislav Dussek and Louis Spohr are introduced by Herr Kiekhöver in Hamburg.
 * July 20 – The chapel created by Napoleon in the Tuileries is officially opened, with Giovanni Paisiello as its musical director.
 * August 15 – Luigi Cherubini, Étienne-Nicolas Méhul, François-Adrien Boieldieu, Rodolphe Kreutzer, Pierre Rode and Nicolò Isouard go into business as publishers of their own music.
 * October 6 – Ludwig van Beethoven writes to his brother Carl from Heiligenstadt, in despair over his increasing deafness.
 * Simon Mayr becomes maestro di cappella at Bergamo Cathedral.

Publications

 * Charles-Simon Catel – Traité d’harmonie (Paris: l'Imprimerie du Conservatoire de Musique)
 * Frédéric Duvernoy – Méthod pour le Cor (Mme Le Roi, Imprimerie du Conservatoire de Musique)
 * Johann Nikolaus Forkel – On Johann Sebastian Bach’s Life, Art, and Work: For Patriotic Admirers of True Musical Art (Leipzig: Hoffmeister und Kühnel)
 * John Gunn – An Essay Theoretical and Practical (London: Preston, for the author)
 * Christian Kalkbrenner – Histoire de la Musique (Paris: Amand Kœnig)
 * Heinrich Christoph Koch – Musikalisches Lexikon (Frankfurt am Main: August Hermann der Jüngere)
 * Jean-Xavier Lefèvre – Méthode de clarinette (Paris: Imprimerie du Conservatoire de Musique)
 * Georg Joseph Vogler – Handbuch zur Harmonielehre (Prague: K. Barth)

Classical music

 * Ludwig van Beethoven
 * Second Symphony
 * 6 Ländler, WoO 15
 * Bagatelle in C Major, WoO 54
 * "No, Non Tubarti", WoO 92a
 * "Ne' giorni tuoi felici", WoO 93
 * "Graf, Graf, Liebster Graf" WoO 101
 * 3 Piano Sonatas, Op. 31
 * 6 Variations in F Major, Op. 34
 * Eroica Variations, Op. 35
 * Matthieu Frédéric Blasius – Clarinet Concerto No. 1
 * Giuseppe Maria Cambini – Wind Quintet Nos.1–3
 * Muzio Clementi – 3 Piano Sonatas, Op. 40
 * Jan Ladislav Dussek
 * Duo in F major, Op. 26
 * Piano Sonata No.17, Op. 43
 * Piano Sonatas Nos. 19–21, Op. 45
 * Piano Sonatas Nos. 22–23, Op. 47
 * Emanuel Aloys Förster – 3 String Quartets, Op. 21
 * Joseph Haydn – Harmoniemesse, his last major work
 * Johann Nepomuk Hummel – Piano Quintet for piano, violin, viola, cello and bass, Op. 87 (inspiration for Schubert's "Trout" quintet)
 * Franz Krommer
 * Flute Concerto No.1, Op. 30
 * Concerto for 2 Clarinets in E-flat major, Op. 35
 * Ignaz Pleyel – Symphonie concertante in F major, B.115
 * Johann Friedrich Reichardt – Das Zauberschloss (singspiel)
 * Louis Spohr - Violin Concerto No. 1, Op. 1
 * Anton Ferdinand Titz – 3 String Quartets
 * Samuel Wesley – Symphony in B-flat
 * Carl Friedrich Zelter – Sammlung kleiner Balladen und Lieder, Z.123

Opera

 * Charles-Simon Catel – Sémiramis
 * Michael Kelly – Urania
 * Giovanni Simone Mayr – I misteri eleusini (premiered Jan. 6 in Milan)
 * Etienne Nicolas Méhul – Le trésor supposé
 * William Reeve – Family Quarrels (comic opera)
 * Carl Maria Von Weber – Peter Schmoll und seine Nachbarn

Births

 * February 7 – Johann Nepomuk Vogl, lyricist (died 1866)
 * February 20 – Charles-Auguste de Bériot, composer and violinist (died 1870)
 * February 25 – Georg Scheurlin, music publisher (died 1872)

 * February 26 – Victor Hugo, librettist and poet (died 1885)
 * March 3 – Adolphe Nourrit, operatic tenor (died 1839)
 * March 5 – James Turle, editor and organist (died 1882)
 * May 31
 * Eduard Grund, composer (died 1871)
 * Cesare Pugni, Italian composer (died 1870)
 * July 3 – Joseph Labitzky, composer and conductor (died 1881)
 * July 12 – Charles-Louis-Joseph Hanssens, composer (died 1852)
 * July 15 – John Barnett, English composer (died 1890)
 * July 24 – Alexandre Dumas, librettist and writer (died 1870)
 * July 27 – Ida Henriette da Fonseca, alto, composer (died 1858)
 * August 13 – Nikolaus Lenau, lyricist and poet (died 1850)
 * August 23 – Manuel Inocêncio Liberato dos Santos, musician and composer (died 1887)
 * August 28 – Karl Joseph Simrock, librettist and poet (died 1876)
 * September 18 – Jean-Amédée Lefroid de Méreaux, composer (died 1874)
 * September 19 – Lajos Kossuth, dedicatee and politician (died 1894)
 * September 24 – Alexander James Edmund Cockburn, librettist and Lord Chief Justice (died 1880)
 * October 7 – Bernhard Molique, composer (died 1869)
 * October 10 – George Pope Morris, librettist and publisher (died 1864)
 * date unknown
 * Jean-Baptiste Duvernoy, pianist and composer (died c. 1880)
 * Ureli Corelli Hill, conductor (died 1875)
 * George Alexander Lee, singer and composer (died 1851)
 * Marion Dix Sullivan, American composer (died 1860)
 * José Zapiola, conductor and composer (died 1885)

Deaths

 * January 27 – Johann Rudolf Zumsteeg, conductor and composer, 42
 * March 7 – Johann Georg Witthauer, composer, 51
 * April 10 – Charlotte Brent, operatic soprano, 67
 * April 18 – Erasmus Darwin, lyricist and physician (born 1731)
 * July 26 – Rose-Adélaïde Ducreux, painter and musician, 41 (yellow fever)
 * July 28 – Giuseppe Sarti, composer, 72
 * August 10 – Antonio Lolli, violinist and composer (born c. 1725)
 * August 23 – Corona Schröter, singer, 51
 * September 28 – Heinrich Harries, lyricist and pastor (born 1762)
 * October 2 – Giuseppe Millico, castrato singer, composer and music teacher, 65
 * October 22 – Samuel Arnold, composer and organist, 62

title: 1802 in music


text:
Peter Guthrie Tait

Peter Guthrie Tait (28 April 1831 – 4 July 1901) was a Scottish mathematical physicist and early pioneer in thermodynamics. He is best known for the mathematical physics textbook Treatise on Natural Philosophy, which he co-wrote with Lord Kelvin, and his early investigations into knot theory.

His work on knot theory contributed to the eventual formation of topology as a mathematical discipline. His name is known in graph theory mainly for Tait's conjecture on cubic graphs. He is also one of the namesakes of the Tait–Kneser theorem on osculating circles.

Early life
Tait was born in Dalkeith on 28 April 1831 the only son of Mary Ronaldson and John Tait, secretary to the 5th Duke of Buccleuch.

He was educated at Dalkeith Grammar School then Edinburgh Academy. He studied Mathematics and Physics at the University of Edinburgh, and then went to Peterhouse, Cambridge, graduating as senior wrangler and first Smith's prizeman in 1852.

As a fellow and lecturer of his college he remained at the University for a further two years, before leaving to take up the professorship of mathematics at Queen's College, Belfast. There he made the acquaintance of Thomas Andrews, whom he joined in researches on the density of ozone and the action of the electric discharge on oxygen and other gases, and by whom he was introduced to Sir William Rowan Hamilton and quaternions.

Middle years
In 1860, Tait succeeded his old master, James D. Forbes, as professor of natural philosophy at the University of Edinburgh, and occupied the Chair until shortly before his death. The first scientific paper under Tait's name only was published in 1860. His earliest work dealt mainly with mathematical subjects, and especially with quaternions, of which he was the leading exponent after their originator, William Rowan Hamilton. He was the author of two text-books on them—one an Elementary Treatise on Quaternions (1867), written with the advice of Hamilton, though not published till after his death, and the other an Introduction to Quaternions (1873), in which he was aided by Philip Kelland (1808–1879), one of his teachers at the University of Edinburgh. Quaternions was also one of the themes of his address as president of the mathematical section of the British Association for the Advancement of Science in 1871.

He also produced original work in mathematical and experimental physics. In 1864, he published a short paper on thermodynamics, and from that time his contributions to that and kindred departments of science became frequent and important. In 1871, he emphasised the significance and future importance of the principle of the dissipation of energy (second law of thermodynamics). In 1873 he took thermoelectricity for the subject of his discourse as Rede lecturer at Cambridge, and in the same year he presented the first sketch of his well-known thermoelectric diagram before the Royal Society of Edinburgh.

Two years later, researches on "Charcoal Vacua" with James Dewar led him to see the true dynamical explanation of the Crookes radiometer in the large mean free path of the molecule of the highly rarefied air. From 1879 to 1888, he engaged in difficult experimental investigations. These began with an inquiry into what corrections were required for thermometers operating at great pressure. This was for the benefit of thermometers employed by the Challenger expedition for observing deep-sea temperatures, and were extended to include the compressibility of water, glass, and mercury. This work led to the first formulation of the Tait equation, which is widely used to fit liquid density to pressure. Between 1886 and 1892 he published a series of papers on the foundations of the kinetic theory of gases, the fourth of which contained what was, according to Lord Kelvin, the first proof ever given of the Waterston-Maxwell theorem (equipartition theorem) of the average equal partition of energy in a mixture of two gases. About the same time he carried out investigations into impact and its duration.

Many other inquiries conducted by him might be mentioned, and some idea may be gained of his scientific activity from the fact that a selection only from his papers, published by the Cambridge University Press, fills three large volumes. This mass of work was done in the time he could spare from his professorial teaching in the university. For example, in 1880 he worked on the Four color theorem and proved that it was true if and only if no snarks were planar.

Later years
In addition, he was the author of a number of books and articles. Of the former, the first, published in 1856, was on the dynamics of a particle; and afterwards there followed a number of concise treatises on thermodynamics, heat, light, properties of matter and dynamics, together with an admirably lucid volume of popular lectures on Recent Advances in Physical Science.

With Lord Kelvin, he collaborated in writing the well-known Treatise on Natural Philosophy. "Thomson and Tait," as it is familiarly called (" T and T' " was the authors' own formula), was planned soon after Lord Kelvin became acquainted with Tait, on the latter's appointment to his professorship in Edinburgh, and it was intended to be an all-comprehensive treatise on physical science, the foundations being laid in kinematics and dynamics, and the structure completed with the properties of matter, heat, light, electricity and magnetism. But the literary partnership ceased in about eighteen years, when only the first portion of the plan had been completed, because each of the members felt he could work to better advantage separately than jointly. The friendship, however, endured for the remaining twenty-three years of Tait's life.

Tait collaborated with Balfour Stewart in the Unseen Universe, which was followed by Paradoxical Philosophy. It was in his 1875 review of The Unseen Universe, that William James first put forth his Will to Believe Doctrine. Tait's articles include those he wrote for the ninth edition of the Encyclopædia Britannica on light, mechanics, quaternions, radiation, and thermodynamics, and the biographical notices of Hamilton and James Clerk Maxwell.

Death
He died in Edinburgh on 4 July 1901, aged 70. He is buried in the second terrace down from Princes Street in the burial ground of St John's Episcopal Church, Edinburgh.

Topology
The Tait conjectures are three conjectures made by Tait in his study of knots. The Tait conjectures involve concepts in knot theory such as alternating knots, chirality, and writhe. All of the Tait conjectures have been solved, the most recent being the Flyping conjecture, proved by Morwen Thistlethwaite and William Menasco in 1991.

Publications

 * Dynamics of a Particle (1856)
 * Treatise on Natural Philosophy (1867); v. 1 and v. 2 (PDF/DjVu at the Internet Archive).
 * An elementary treatise on quaternions (1867); PDF/DjVu Copy of the 1st ed. at the Internet Archive and PDF/DjVu Copy of the 3rd ed. at the Internet Archive.
 * Elements of Natural Philosophy (1872); (PDF/DjVu at the Internet Archive). A "non-mathematical portion of Treatise on Natural Philosophy".
 * Sketch of Thermodynamics (1877); PDF/DjVu Copy at the Internet Archive.
 * Recent Advances in Physical Science (1876); PDF/DjVu Copy at the Internet Archive.
 * Heat (1884); PDF/DjVu Copy at the Internet Archive.
 * Light (1884); PDF/DjVu Copy at the Internet Archive.
 * Properties of Matter (1885); PDF/DjVu Copy at the Internet Archive.
 * Dynamics (1895); PDF/DjVu Copy at the Internet Archive.
 * The Unseen Universe (1875; new edition, 1901)
 * Scientific papers vol. 1 (1898–1900) PDF/DjVu Copy at the Internet Archive.
 * Scientific papers vol. 2 (1898–1900) PDF/DjVu Copy at the Internet Archive.

Private life
Tait was married to Margaret Archer Porter (1839–1926), the sister of (1) William Archer Porter, a lawyer and educationist who served as the Principal of Government Arts College, Kumbakonam and tutor and secretary to the Maharaja of Mysore, (2) James Porter (Master of Peterhouse, Cambridge), and (3) Jane Bailie Porter, who married Alexander Crum Brown, the Scottish organic chemist.

Tait was an enthusiastic golfer and, of his seven children, two, Frederick Guthrie Tait (1870–1900) and John Guthrie Tait (1861–1945) went on to become gifted amateur golf champions. He was an all-round sportsman and represented Scotland at international level in rugby union. (In 1891, Tait invoked the Magnus effect to explain the influence of spin on the flight of a golf ball.) His daughter, Edith, married Rev. Harry Reid, who later became Bishop of Edinburgh. Another son, William, was a civil engineer.

Recognition
Tait was a lifelong friend of James Clerk Maxwell, and a portrait of Tait by Harrington Mann is held in the James Clerk Maxwell Foundation museum in Edinburgh.

There are several portraits of Tait by Sir George Reid. One, painted about 1883, is owned by the National Galleries of Scotland, to which it was given by the artist in 1902. Another portrait was unveiled at Peterhouse, Cambridge in October 1902, paid for by the Master and Fellows of Peterhouse, where Tait had been an Honorary Fellow.

One of the chairs in the Department of Physics at the University of Edinburgh is the Tait professorship.

Peter Guthrie Tait Road at the University of Edinburgh King's Buildings complex is named in his honour.

title: Peter Guthrie Tait