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Delusional disorder

Delusional disorder, traditionally synonymous with paranoia, is a mental illness in which a person has delusions, but with no accompanying prominent hallucinations, thought disorder, mood disorder, or significant flattening of affect. Delusions are a specific symptom of psychosis. Delusions can be bizarre or non-bizarre in content; non-bizarre delusions are fixed false beliefs that involve situations that could occur in real life, such as being harmed or poisoned. Apart from their delusion or delusions, people with delusional disorder may continue to socialize and function in a normal manner and their behavior does not necessarily seem odd. However, the preoccupation with delusional ideas can be disruptive to their overall lives.

For the diagnosis to be made, auditory and visual hallucinations cannot be prominent, though olfactory or tactile hallucinations related to the content of the delusion may be present. The delusions cannot be due to the effects of a drug, medication, or general medical condition, and delusional disorder cannot be diagnosed in an individual previously properly diagnosed with schizophrenia. A person with delusional disorder may be high functioning in daily life. Recent and comprehensive meta-analyses of scientific studies point to an association with a deterioration in aspects of IQ in psychotic patients, in particular perceptual reasoning, although, the between-group differences were small.

According to German psychiatrist Emil Kraepelin, patients with delusional disorder remain coherent, sensible and reasonable. The Diagnostic and Statistical Manual of Mental Disorders (DSM) defines six subtypes of the disorder: erotomanic (belief that someone is in love with one), grandiose (belief that one is the greatest, strongest, fastest, richest, or most intelligent person ever), jealous (belief that one is being cheated on), persecutory (delusions that one or someone one is close to is being malevolently treated in some way), somatic (belief that one has a disease or medical condition), and mixed, i.e., having features of more than one subtype.

Delusions also occur as symptoms of many other mental disorders, especially the other psychotic disorders.

The DSM-IV and psychologists agree that personal beliefs should be evaluated with great respect to cultural and religious differences, as some cultures have normalized beliefs that may be considered delusional in other cultures.

An earlier, now-obsolete, nosological name for delusional disorder was "paranoia". This should not be confused with the modern definition of paranoia (i.e., persecutory ideation specifically).

Classification
The International Classification of Diseases classifies delusional disorder as a mental and behavioural disorder. Drs; Diagnosis of a specific type of delusional disorder can sometimes be made based on the content of the delusions, to wit, the Diagnostic and Statistical Manual of Mental Disorders (DSM) enumerates seven types:
 * Erotomanic type (erotomania): delusion that another person, often a prominent figure, is in love with the individual. The individual may breach the law as they try to obsessively make contact with the desired person.
 * Grandiose type (megalomania): delusion of inflated worth, power, knowledge, identity or believing oneself to be a famous person, claiming the actual person is an impostor or an impersonator.
 * Jealous type: delusion that the individual's sexual partner is unfaithful when it is untrue. The patient may follow the partner, check text messages, emails, phone calls etc. in an attempt to find "evidence" of the infidelity.
 * Persecutory type: This delusion is a common subtype. It includes the belief that the person (or someone to whom the person is close) is being malevolently treated in some way. The patient may believe that they have been drugged, spied upon, harmed, harassed and so on and may seek "justice" by making reports, taking action or even acting violently.
 * Somatic type: delusions that the person has some physical defect or general medical condition
 * Mixed type: delusions with characteristics of more than one of the above types but with no one theme predominating.
 * Unspecified type: delusions that cannot be clearly determined or characterized in any of the categories in the specific types.

Signs and symptoms
The following can indicate a delusion:
 * 1) An individual expresses an idea or belief with unusual persistence or force, even when evidence suggests the contrary.
 * 2) That idea appears to have an undue influence on the person's life, and the way of life is often altered to an inexplicable extent.
 * 3) Despite their profound conviction, there is often a quality of secretiveness or suspicion when the person is questioned about it.
 * 4) The individual tends to be humorless and oversensitive, especially about the belief.
 * 5) There is a quality of centrality: no matter how unlikely it is that these strange things are happening to the person, they accept them relatively unquestioningly.
 * 6) An attempt to contradict the belief is likely to arouse an inappropriately strong emotional reaction, often with irritability and hostility. They will not accept any other opinions.
 * 7) The belief is, at the least, unlikely, and out of keeping with the individual's social, cultural, and religious background.
 * 8) The person is emotionally over-invested in the idea and it overwhelms other elements of their psyche.
 * 9) The delusion, if acted out, often leads to behaviors which are abnormal, and out of character, although perhaps understandable in light of the delusional beliefs.
 * 10) Other people who know the individual observe that the belief and behavior are uncharacteristic and alien.

Additional characteristic of delusional disorder include the following:
 * 1) It is a primary disorder.
 * 2) It is a stable disorder characterized by the presence of delusions to which the patient clings with extraordinary tenacity.
 * 3) The illness is chronic and frequently lifelong.
 * 4) The delusions are logically constructed and internally consistent.
 * 5) The delusions do not interfere with general logical reasoning (although within the delusional system the logic is perverted) and there is usually no general disturbance of behavior. If disturbed behavior does occur, it is directly related to the delusional beliefs.
 * 6) The individual experiences a heightened sense of self-reference.  Events which, to others, are nonsignificant are of enormous significance to them, and the atmosphere surrounding the delusions is highly charged.

However, this should not be confused with gaslighting, where a person denies the truth, and causes the one being gaslit to think that they are being delusional.

Causes
The cause of delusional disorder is unknown, but genetic, biochemical, and environmental factors may play a significant role in its development. Some people with delusional disorders may have an imbalance in neurotransmitters, the chemicals that send and receive messages to the brain. There does seem to be some familial component, and immigration (generally for persecutory reasons), drug abuse, excessive stress, being married, being employed, low socioeconomic status, celibacy among men, and widowhood among women may also be risk factors. Delusional disorder is currently thought to be on the same spectrum or dimension as schizophrenia, but people with delusional disorder, in general, may have less symptomatology and functional disability.

Diagnosis
Differential diagnosis includes ruling out other causes such as drug-induced conditions, dementia, infections, metabolic disorders, and endocrine disorders. Other psychiatric disorders must then be ruled out. In delusional disorder, mood symptoms tend to be brief or absent, and unlike schizophrenia, delusions are non-bizarre and hallucinations are minimal or absent.

Interviews are important tools to obtain information about the patient's life situation and history to help make a diagnosis. Clinicians generally review earlier medical records to gather a full history. Clinicians also try to interview the patient's immediate family, as this can be helpful in determining the presence of delusions. The mental status examination is used to assess the patient's current mental condition.

A psychological questionnaire used in the diagnosis of the delusional disorder is the Peters Delusion Inventory (PDI) which focuses on identifying and understanding delusional thinking. However, this questionnaire is more likely used in research than in clinical practice.

In terms of diagnosing a non-bizarre delusion as a delusion, ample support should be provided through fact checking. In case of non-bizarre delusions, Psych Central  notes, "All of these situations could be true or possible, but the person suffering from this disorder knows them not to be (e.g., through fact-checking, third-person confirmation, etc.)."

Treatment
A challenge in the treatment of delusional disorders is that most patients have limited insight, and do not acknowledge that there is a problem. Most patients are treated as out-patients, although hospitalization may be required in some cases if there is a risk of harm to self or others. Individual psychotherapy is recommended rather than group psychotherapy, as patients are often quite suspicious and sensitive. Antipsychotics are not well tested in delusional disorder, but they do not seem to work very well, and often have no effect on the core delusional belief. Antipsychotics may be more useful in managing agitation that can accompany delusional disorder. Until further evidence is found, it seems reasonable to offer treatments which have efficacy in other psychotic disorders.

There is a certain amount of evidence that alternative treatment-regimes (beyond conventional attempted treatment with antipsychotics) may include clomipramine for people with the somatic subtype of paranoia. There is a dearth of well-published studies investigating the effectiveness of trimipramine; another derivative of tricyclic-antidepressant imipramine and one which has modest anti-psychotic properties weakly analogous to those of clozapine; in delusional disorder per-se. However, trimipramine was compared to a combination of amitriptyline and haloperidol in a double-blinded trial involving patients with severe, psychotic depression (specifically with customary delusional features) and appeared favourable in its treatment.

Psychotherapy for patients with delusional disorder can include cognitive therapy which is conducted with the use of empathy. During the process, the therapist can ask hypothetical questions in a form of therapeutic Socratic questioning. This therapy has been mostly studied in patients with the persecutory type. The combination of pharmacotherapy with cognitive therapy integrates treating the possible underlying biological problems and decreasing the symptoms with psychotherapy as well. Psychotherapy has been said to be the most useful form of treatment because of the trust formed in a patient and therapist relationship.

Supportive therapy has also been shown to be helpful. Its goal is to facilitate treatment adherence and provide education about the illness and its treatment.

Furthermore, providing social skills training has been found to be helpful for many people. It can promote interpersonal competence as well as confidence and comfort when interacting with those individuals perceived as a threat.

Insight-oriented therapy is rarely indicated or contraindicated; yet there are reports of successful treatment. Its goals are to develop therapeutic alliance, containment of projected feelings of hatred, powerlessness, and badness; measured interpretation as well as the development of a sense of creative doubt in the internal perception of the world. The latter requires empathy with the patient's defensive position.

Epidemiology
Delusional disorders are uncommon in psychiatric practice, though this may be an underestimation due to the fact that those with the condition lack insight and thus avoid psychiatric assessment. The prevalence of this condition stands at about 24 to 30 cases per 100,000 people while 0.7 to 3.0 new cases per 100,000 people are reported every year. Delusional disorder accounts for 1–2% of admissions to inpatient mental health facilities. The incidence of first admissions for delusional disorder is lower, from 0.001 to 0.003%.

Delusional disorder tends to appear in middle to late adult life, and for the most part first admissions to hospital for delusional disorder occur between age 33 and 55. It is more common in women than men, and immigrants seem to be at higher risk.

Criticism
In some situations, the delusion may turn out to be true belief. For example, in delusional jealousy, where a person believes that the partner is being unfaithful (in extreme cases perhaps going so far as to follow the partner into the bathroom, believing the other to be seeing a lover even during the briefest of separations), it may actually be true that the partner is having sexual relations with another person. In this case, the delusion does not cease to be a delusion because the content later turns out to be verified as true or the partner actually chose to engage in the behavior of which they were being accused.

In other cases, a belief may be incorrectly deemed delusional by a doctor or psychiatrist who subjectively concludes that a patient's assertions are unlikely, bizarre, or held with excessive conviction. Psychiatrists rarely have the time or resources to check the validity of a person's claims leading some true beliefs to be erroneously classified as delusional. This is known as the Martha Mitchell effect, named after the wife of US Attorney General John Mitchell and derived from the initial response to her allegations of illegal activity taking place in the White House. At the time, her claims were thought to be signs of mental illness; only after the Watergate scandal broke were her claims corroborated and her sanity thus confirmed.

Similar factors have led to criticisms of Jaspers' definition of delusion as being ultimately 'un-understandable'. Critics (such as R. D. Laing) have argued that this leads to the diagnosis of delusions being based on the subjective understanding of a particular psychiatrist, who may not have access to all the information that might make a belief otherwise interpretable.

Another difficulty with the diagnosis of delusions is that almost all of these features can be found in "normal" beliefs. Many religious beliefs hold exactly the same features, yet are not universally considered delusional. For instance, if a person was holding a true belief then they will of course persist with it. This can cause the disorder to be misdiagnosed by psychiatrists. These factors have led the psychiatrist Anthony David to write that "there is no acceptable (rather than accepted) definition of a delusion."

In popular culture
In the 2010 psychological thriller Shutter Island, directed by Martin Scorsese and starring Leonardo DiCaprio, delusional disorder is portrayed along with other disorders. An Indian movie Anantaram (Thereafter) directed by Adoor Gopalakrishnan also portrays the complex nature of delusions. The plot of the French movie He Loves Me... He Loves Me Not revolves around a case of erotomania, as does the plot of the Ian McEwan novel, Enduring Love.

title: Delusional disorder


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Charles Pritchard

Reverend Charles Pritchard (29 February 1808 – 28 May 1893) was a British astronomer, clergyman, and educational reformer. He founded the Clapham Grammar School in 1834 and included sciences in the curriculum. A chapel was erected in 1846.

Biography
He was born at Alberbury, Shropshire, fourth son of William Pritchard, a failed manufacturer who later moved to London where he attended the Merchant Taylor's School and Poplar Academy where he was taught by John Stock, the progressive educationalist. Pritchard later described his studies as consisting of "a systematic course of instruction relating to physical phenomena". At sixteen he was enrolled as a sizar at St John's College, Cambridge, graduating in 1830 as fourth wrangler. In 1832 he was elected a fellow of his college, and in the following year he was ordained, and became head of a private school at Stockwell. From 1834 to 1862 he was headmaster of Clapham grammar school. He then retired to Freshwater, in the Isle of Wight, and took an active interest in the affairs of the Royal Astronomical Society, of which he became honorary secretary in 1862 and president in 1866. His sister, Margaret died this same year.

His career as a professional astronomer began in 1870, when he was elected Savilian professor of astronomy at the University of Oxford. At his request the university decided to build a fine equatorial telescope for the instruction of his class and for purposes of research, a scheme which, as a result of Warren de la Rue's munificent gift of instruments from his private observatory at Cranford, expanded into the establishment of the new university observatory. By De la Rue's advice, Pritchard began his career there with a determination of the physical libration of the moon, or the nutation of its axis.

In 1882 Pritchard commenced a systematic study of stellar photometry. For this purpose he employed an instrument known as the "wedge photometer", with which he measured the relative brightness of 2,784 stars between the North Pole and about -10° declination. The results were published in 1885 in his Uranometria Nova Oxoniensis, and their importance was recognized by the bestowal in 1886 upon him, conjointly with Professor Pickering, of the Gold Medal of the Royal Astronomical Society.

He then decided to experiment with applying photography to the determination of stellar parallax. With the object of testing the capabilities of the method, he took for his first essay the well-known star 61 Cygni, and his results agreed so well with those previously attained that he undertook the systematic measurement of the parallaxes of second-magnitude stars, and published the outcome in the third and fourth volumes of the Publications of the Oxford University Observatory. Although some lurking errors impaired the authority of the concluded parallaxes this work ranks as a valuable contribution to astronomy, since it showed the possibility of employing photography in such delicate investigations.

When an international survey of the heavens was proposed, the zone between 25° and 31° north declination was allotted to him, and at the time of his death some progress had been made in recording its included stars. Pritchard became a fellow of New College, Oxford, in 1883, and an honorary fellow of St John's College, Cambridge, in 1886. He was elected a fellow of the Royal Society in 1840, and in 1892 was awarded one of the royal medals for his work on photometry and stellar parallax.

Family
A son, Sir Charles Bradley Pritchard, was an administrator in British India.

Works

 * Occasional thoughts of an astronomer on nature and revelation (1889)
 * Modern science and natural religion (1874)
 * Modern science and natural religion (1874)

Obituaries

 * MNRAS 54 (1894) 198
 * Obs 16 (1894) 256

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

title: Charles Pritchard


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Ruby Murray

Ruby Florence Murray (29 March 1935 – 17 December 1996) was a Northern Irish singer. One of the most popular singers in the British Isles in the 1950s, she scored ten hits in the UK Singles Chart between 1954 and 1959. She also made pop chart history in March 1955 by having five hits in the Top Twenty in a single week.

Child star
Ruby Florence Murray was born near the Donegall Road in south Belfast, the youngest child in a Protestant family. She had surgery at six weeks of age due to swollen glands, and as a result, had a very husky voice. Entering a public speaking contest run by Eglinton Young Farmers Club, Londonderry in March 1947, she won a special prize for the youngest competitor under 18. A performance at the Ballymena Variety Theatre in February 1948 received a wonderful reception and she then toured in Northern Ireland as a child singer. Murray first appeared on television at the age of 12, having been spotted by producer Richard Afton. Owing to laws governing children performing, Murray had to delay her start in the entertainment industry. She returned to Belfast and full-time education until she was 14.

Chart success
Murray kept busy on the variety stage in Northern Ireland in the early 1950s and in 1954 she joined a touring revue called "Yankee Doodle Blarney" which gave her very useful exposure on the English variety stages. Richard Afton offered her the position of resident singer on the BBC's Quite Contrary television show, to replace Joan Regan. After being again spotted by Ray Martin on the first Quite Contrary show, Murray was signed to Columbia and her first single, "Heartbeat", reached No. 3 in the UK Singles Chart in December 1954. "Softly, Softly", her second single, reached number one in early 1955. That year Murray set a pop chart record by having five hits in the Top Twenty in one week, a feat unmatched for many years. In 2014, the Guinness Book of World Records issued three certificates confirming that at the date of issue, nobody had beaten this record, although it was shared with three other singers. The record by a female singer still stood as of 2020 but was broken by Taylor Swift in 2022.

The 1950s was a busy period for Murray, during which she had her own television show, starred at the London Palladium with Norman Wisdom, appeared in a Royal Command Performance (1955), and toured the world. In a period of 52 weeks, starting on 3 December 1954 and lasting until the end of November 1955, Murray constantly had at least one single in the UK charts – this at a time when only a Top 20 was listed.

Murray appeared in her only film role, as Ruby, in A Touch of the Sun, a 1956 farce with Frankie Howerd and Dennis Price. A couple of hits followed later in the decade; "Goodbye Jimmy, Goodbye", a No. 10 hit in 1959, was her final appearance in the charts. EMI put together a compilation album of her hits on CD in 1989, including songs that regularly featured in her act; "Mr. Wonderful", "Scarlet Ribbons" and "It's the Irish in Me". They updated this with the release of EMI Presents The Magic of Ruby Murray in 1997 and a four CD album, Anthology – The Golden Anniversary Collection, in 2005, the 50th anniversary of her peak successes on the charts.

Legacy
Murray's popularity led to her name being adopted in Cockney rhyming slang as a rhyme for "curry". The phrase "have a ruby" appears in various episodes of the BBC TV comedy series Only Fools and Horses. It also appeared in another BBC sitcom series, The Royle Family.

A play about Murray's life, Ruby, written by the Belfast playwright Marie Jones, opened at the Group Theatre in Belfast in April 2000. A second play, by Michael Cameron, opened in Belfast on 13 February 2019 and was sold out at all performances.

Personal life
In 1957, while working in Blackpool, Murray met Bernie Burgess, a member of a successful television and recording vocal quartet, the Four Jones Boys. Shortly afterwards she left Northern Ireland to marry him and live with him in Northampton. Burgess, contrary to press reports, did not become her manager, but rather his role was that of a supporting husband. The couple included a song-and-dance segment in Murray's act during the 1960s.

Murray struggled with alcoholism for most of her life and this contributed to the breakdown of her marriage in 1974. The divorce was finalised in 1976 and Murray moved to Torquay to live with an old friend, Ray Lamar, a former stage dancer and theatre impresario, who was 18 years her senior. They married in 1991 and spent the evening with a small party of friends and family at an Italian restaurant in Babbacombe.

Murray had two children from her marriage to Burgess, Julie (b. 1960) and Tim (b. 1965). Tim died unexpectedly from a heart condition in July 2020, aged 55.

Although her days as a major star were long over, Murray continued performing until close to the end of her life. Spending her last couple of years in Asprey's Nursing Home, she often delighted her carers with a song, and was visited by her friend Max Bygraves. She died of liver cancer on 17 December 1996, aged 61.

Ray Lamar died on 3 August 2005 from complications of pneumonia, aged 87.

Singles discography

 * "Heartbeat" (1954) – UK number 3
 * "Softly, Softly" (1955) – UK number 1
 * "Happy Days and Lonely Nights" (1955) – UK number 6
 * "Let Me Go Lover" (1955) – UK number 5
 * "If Anyone Finds This, I Love You" (1955) – UK number 4 †
 * "Evermore" (1955) – UK number 3
 * "I'll Come When You Call" (1955) – UK number 6
 * "The Very First Christmas of All" (1955) – UK number 9 (Record Mirror)
 * "You are My First Love" (1956) – UK number 16
 * "Real Love" (1958) – UK number 18
 * "Goodbye Jimmy, Goodbye" (1959) – UK number 10

† Ruby Murray with Anne Warren

For further discography, see this page on the official Ruby Murray website.

title: Ruby Murray


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Hagakure

Hagakure (Kyūjitai: 葉隱; Shinjitai: 葉隠; meaning Hidden by the Leaves or Hidden Leaves), or Hagakure Kikigaki (葉隠聞書), is a practical and spiritual guide for a warrior, drawn from a collection of commentaries by the clerk Yamamoto Tsunetomo, former retainer to Nabeshima Mitsushige (July 10, 1632 – July 2, 1700), the third ruler of what is now Saga Prefecture in Japan. compiled these commentaries from his conversations with Tsunetomo from 1709 to 1716; however, it was not published until many years afterwards. Written during a time when there was no officially sanctioned samurai fighting, the book grapples with the dilemma of maintaining a warrior class in the absence of war and reflects the author's nostalgia for a world that had disappeared before he was born. Hagakure was largely forgotten for two centuries after its composition, but it came to be viewed as the definitive guide of the armed forces of the Empire of Japan during the Pacific War. Hagakure is also known as The Book of the Samurai, Analects of Nabeshima or Hagakure Analects.

Content
The book records Yamamoto's views on bushido, the warrior code of the samurai. Hagakure is sometimes said to assert that bushido is really the "Way of Dying" or living as though one was already dead, and that a samurai must be willing to die at any moment in order to be true to his lady/lord. His saying "the way of the warrior is death" was a summation of the willingness to sacrifice that bushido codified. Hagakure's text is occasionally misinterpreted as meaning that bushido is a code of death. However, the true meaning is that by having a constant awareness of death, people can achieve a transcendent state of freedom, whereby "it is possible to perfectly fulfill one's calling as a warrior."

Historical context
After the Tokugawa shogunate suppressed the Shimabara Rebellion in 1638, Japan experienced no warfare for about two centuries. Private feuding and dueling between samurai was also suppressed. Yamamoto Tsunetomo was born in 1659, after the end of officially sanctioned samurai fighting. He had no personal combat experience and when he was employed, he worked as a scribe. By the late 1600s and early 1700s, samurai faced the dilemma of maintaining a warrior class in the absence of war, and Hagakure reflects this uncertainty. Written late in the author's life, the book also reflects his nostalgia for a world that had disappeared before his birth.

Reception
Hagakure was largely forgotten for two centuries. The first modern edition appeared in 1900, and it did not receive much attention during the first decades of the century. Hagakure came to be viewed as a definitive book of the samurai only during the Pacific War. According to Mark Ravina, "Rather than an account of samurai tradition, this work serves as an example of what the Japanese army thought Japanese soldiers should believe about samurai practice." In the post-war era, the nationalist author and poet, Yukio Mishima, was inspired by Hagakure and wrote his own book in praise of the work. Quotations from Hagakure are used as a narrative device in the 1999 American gangster film Ghost Dog: The Way of the Samurai.

Editions

 * Hagakure: The Secret Wisdom of the Samurai, Yamamoto Tsunetomo, Translated by Alexander Bennett, Tuttle Publishing, 2014, ISBN 978-4-8053-1198-1 (Full Translation)
 * The Art of the Samurai: Yamamoto Tsunetomo's Hagakure, Yamamoto Tsunetomo, Translated by Barry D. Steben, Duncan Baird, September 2008, ISBN 1-84483-720-3 (Partial translation)
 * Hagakure, The Way of the Samurai, Yamamoto Tsunetomo, Translated by Takao Mukoh, Angkor Verlag, 2000 (Reprint), ISBN 3-8311-1530-3
 * Hagakure, The manga edition, Yamamoto Tsunetomo, Translated by William Scott Wilson, a comic book/manga version, adapted by Sean Michael Wilson and Chie Kutsuwada, Kondansha International Ltd., 2011.
 * Bushido, The Way of the Samurai, Yamamoto Tsunetomo, Translated by Justin F. Stone and Minoru Tanaka, Square One Publishers, 2003, ISBN 0-7570-0026-6

title: Hagakure


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George Grove

Sir George Grove (13 August 1820 –28 May 1900) was an English engineer and writer on music, known as the founding editor of Grove's Dictionary of Music and Musicians.

Grove was trained as a civil engineer, and successful in that profession, but his love of music drew him into musical administration. When responsible for the regular orchestral concerts at the Crystal Palace, he wrote a series of programme notes from which eventually grew his musical dictionary. His interest in the music of Franz Schubert, which was neglected in England at that point in the nineteenth century, led him and his friend Arthur Sullivan to go to Vienna in search of undiscovered Schubert manuscripts. Their researches led to their discovery of the lost score of Schubert's Rosamunde music, several of his symphonies and other music in 1867, leading to a revival of interest in Schubert's work.

Grove was the first director of the Royal College of Music, from its foundation in 1883 until his retirement in 1894. He recruited leading musicians including Hubert Parry and Charles Villiers Stanford as members of the College faculty and established a close working relationship with London's older conservatoire, the Royal Academy of Music.

In addition to his musical work, Grove had a deep and scholarly knowledge of the Bible. He contributed to the English literature on the subject, including a concordance in 1854 and about a thousand pages of Sir William Smith's 1863 Bible Dictionary. He was a co-founder of the Palestine Exploration Fund.

Early years
Grove was born in Clapham, the eighth of the eleven children of Thomas Grove (1774–1852), fishmonger and venison dealer, and his wife, Mary ( Blades; 1784–1856). A younger sister, Eleanor, was the founding principal of College Hall, London.

He went to a preparatory school, on Clapham Common, where one of his schoolfellows was George Granville Bradley, later Dean of Westminster, whose sister Grove subsequently married. He next entered Stockwell (later known as Clapham) Grammar School, run by Charles Pritchard, the astronomer, who was inspired by the progressive principles of King's College, London. The educational curriculum was based on classics, divinity, mathematics and natural philosophy, and rigorously tested by annual examination. Pritchard also encouraged his pupils to develop interests in literature and music.

Grove was a regular worshipper at Holy Trinity, Clapham, where he listened to the music of Bach and Handel. By the age of sixteen, he was competent in classics and mathematics; he left the school in 1836 and was apprenticed to Alexander Gordon, a well-known civil engineer in Westminster. In his free time, he immersed himself in music, attending concerts and studying scores.

After completing his apprenticeship, Grove was admitted as a graduate of the Institution of Civil Engineers, in 1839. A year later he went to Glasgow, gaining further experience in the factory of Robert Napier. In 1841, Grove had an affair with a woman called Elizabeth Blackwell, who gave birth to his illegitimate son, George Grove Blackwell, in March 1842. Between 1841 and 1846, Grove spent most of his time in the West Indies, as resident engineer during the building of cast-iron lighthouses.

After this he joined the staff of the Chester and Holyhead Railway and then became assistant to Edwin Clark, working on the Britannia Bridge across the Menai Strait. An account of the first floating of the tubes of the bridge is recorded in The Spectator of 23 June 1849, which was Grove's first appearance in print. During this period, he lived in Chester, hearing music in the cathedral and also becoming familiar with Welsh folksong.

Music and biblical scholarship
While working on the Britannia Bridge Grove came into contact with Robert Stephenson, Isambard Kingdom Brunel, Sir Charles Barry and other eminent visitors to the works. "These distinguished men", Grove later recalled, "noticed me and were as good as gold to me. They counselled me to go to London and forced me into the secretaryship of the Society of Arts, then vacant by the retirement of Mr. Scott Russell." This was in 1849, when the Great Exhibition of 1851 was in preparation. Grove was the society's secretary for the duration of the exhibition.

On 23 December 1851, he married Harriet Bradley, the sister of his old school friend George Bradley. After the Great Exhibition closed in 1852, its principal building, known as "the Crystal Palace", was dismantled and rebuilt in the south London suburb of Sydenham as a centre for education, the arts and leisure. Grove was appointed secretary of the Crystal Palace. He engaged a wind band and a conductor, Heinrich Schallehn. The latter was found to be unsatisfactory, and was replaced by August Manns, who, with Grove's encouragement, developed the band into a full-sized symphony orchestra. With programmes chosen by Grove and Manns, the Crystal Palace concerts became a central feature of London's musical scene and remained so until the end of the century.

Grove wrote the programme notes for the concerts. In 1901, a biographer wrote:
 * The daily and weekly orchestral performances at Sydenham prompted those admirable analytical notices of musical compositions with which the name of George Grove was so long and is so favourably associated. He had always shown a great fondness for music, but had never received any technical training in the art. Entirely self-taught, his knowledge was acquired solely by 'picking up' information. "I wish it to be distinctly understood," he said, "that I have always been a mere amateur in music. I wrote about the symphonies and concertos because I wished to try to make them clear to myself and to discover the secret of the things that charmed me so; and from that sprang a wish to make other amateurs see it in the same way."

Grove's musical analyses avoided all hint of technical jargon and tried to make clear to everyone who read them what, in Grove's opinion, listeners should be aware of in each piece. In a note on Mozart's Symphony No. 39, after referring to Mozart's extraordinary productivity in the year 1788, Grove wrote:
 * The circumstances which necessitated such fearful exertion on this and many other occasions in Mozart's life we have no means of ascertaining. Whatever they were, they were in accordance with a common custom of Nature. She seems to delight in condemning her most gifted sons to an ordeal the very reverse of that which we should anticipate. It seems equally true in Art and in Morals, that it is not by indulgence and favour, but by difficulty and trouble, that the spirit is formed; and in all ages of the world our Davids, Shakspeares, Dantes, Mozarts, and Beethovens must submit to processes which none but their great spirits could survive – to a fiery trial of poverty, ill health, neglect, and misunderstanding – and be "tried as silver is tried," that they may become the teachers of their fellow-men to all time, and shine, like stars in the firmament, for ever and ever.

Grove's Crystal Palace programme notes did not concentrate solely on his favourite Austro-German composers. He embraced a representative selection of composers, notably the Frenchmen Berlioz, Bizet, Delibes, Gounod, Massenet and Saint-Saëns, and the rising generations of British composers – Arthur Sullivan, Hubert Parry, Charles Villiers Stanford, Hamish MacCunn, Edward German and Granville Bantock. Among the composers whom Grove sought to popularise was Schubert, whose music was largely neglected in England. Grove and Manns presented the first performance in England of the Great C major Symphony. Together with his friend Arthur Sullivan, Grove went to Vienna in 1867 in search of Schubert manuscripts. They found several of Schubert's symphonies and much other music, some of which they copied. They were particularly excited about their final discovery, which Grove described thus: "I found, at the bottom of the cupboard, and in its farthest corner, a bundle of music-books two feet high, carefully tied round, and black with the undisturbed dust of nearly half-a-century. … These were the part-books of the whole of the music in Rosamunde, tied up after the second performance in December, 1823, and probably never disturbed since. Dr. Schneider [Schubert's nephew] must have been amused at our excitement; but let us hope that he recollected his own days of rapture; at any rate, he kindly overlooked it, and gave us permission to take away with us and copy what we wanted."

In the early years of the Crystal Palace, Grove devoted much of his leisure time to Biblical scholarship. Discovering that there was no full concordance of the proper names in the Bible, Grove, helped by his wife, began work in 1853 making a complete index of each occurrence of every proper name in the Bible, including the Apocrypha. Between 1860 and 1863, Grove was assistant editor to Sir William Smith in a comprehensive Bible dictionary, contributing more than a thousand pages. Some entries written by Grove, such as that on the prophet Elijah, were equivalent almost to book-length. He visited the Holy Land in 1859 and 1861, and helped to found the Palestine Exploration Fund, of which he became honorary secretary, labouring incessantly on its behalf. The Archbishop of York said that Grove was "virtually the founder and institutor of the Society, and has done wonders for it throughout." Grove later observed, "People will insist on thinking of me as a musician, which I really am not in the very least degree. I took quite as much interest in my investigations into the natural features and the little towns of Palestine which I did for Smith's Dictionary of the Bible or for Arthur Stanley's Sinai and Palestine, as I did for Beethoven and Mendelssohn, indeed perhaps more so."

Grove's Dictionary of Music and Musicians
After nearly twenty years of service at the Crystal Palace, Grove resigned the secretaryship at the end of 1873 and accepted an offer from the publishers Macmillan and Co. to join their staff and become a director of the firm. He edited Macmillan's Magazine and wrote a primer of geography for Macmillan's "History Primers". By far the most important outcome of his connection with Macmillan was A Dictionary of Music and Musicians, for which his name is best remembered. The idea of the dictionary was entirely his own. He stated, in the prospectus of the dictionary, in March 1874, that "The want of English works on the history, theory, or practice of Music, or the biographies of musicians accessible to the non-professional reader, has long been a subject of remark."

Grove conceived of a work to fill the gap he had identified; he originally proposed two volumes of about 600 pages each, but by the time of its first publication, it ran to four volumes containing a total of 3,125 pages. It was issued by Macmillan in alphabetical volumes over a 12-year period ending in 1889. Grove criticised Parry, a leading contributor, for being "inclined to be wordy and diffuse", but articles by Grove on his own particular interests, Beethoven, Mendelssohn and Schubert, were even longer. The Musical Times wrote of the work, "His masterly biographies of Beethoven, Mendelssohn, and Schubert are models of biographical literature, and are written in a most fascinating style. He made two special journeys to Germany to obtain materials for his Mendelssohn article, and more than two to Vienna in connection with Schubert and Beethoven."

Royal College of Music
In the 1880s, London's musical academies were in poor shape. The Royal Academy of Music was moribund, and the National Training School for Music, of which Sullivan was the reluctant and ineffectual head, was in financial and administrative difficulties. There was a proposal to merge the two bodies to create a single effective conservatoire, but the Royal Academy insisted on retaining its independence and later revitalised itself under the leadership of Alexander Mackenzie. The National Training School was re-formed as the Royal College of Music in 1882, and Grove was appointed its first director. Throughout 1882 he led a successful fund-raising campaign that ensured the official opening of the new college by the Prince of Wales on 7 May 1883. Grove received a knighthood on the same day. The teaching staff, whom he appointed, were led by Parry and Stanford, and, as a biographer of Grove says, "carried the college with distinction into the twentieth century."

Grove focused the college's attention on two main activities: practical training and examining. He was determined to raise the general standard of orchestral playing by replacing the existing ad hoc methods of apprentice-based training, private lessons, or study abroad. His second focus, examination, followed the Victorian trend to form professional bodies regulating and standardising the activity of members of each profession. An example is the Institution of Civil Engineers to which Grove had been admitted in 1839. When the Royal Charter establishing the college was being drawn up, Grove ensured that, unlike the Royal Academy, the college should have degree-awarding powers. Mackenzie, seeing the prospect that the new institution would overshadow the Academy, successfully proposed that both bodies should award qualifications jointly. Grove agreed, realising that this course would do much to dispel the damaging hostility that existed between the Academy and the college.

The new Associated Board of the Royal Schools of Music thus formed offered musical qualifications to external candidates from anywhere in the British Empire who could meet its rigorous standards. 1,141 candidates entered for the first examinations in 1890, despite the high entry fee of two guineas. The income helped both institutions to keep their own student fees at an affordable level, which enabled the college to make a full three-year course of study its basic standard. Because of the thorough training thus offered, the high standard of playing of the college's students quickly became known. Leading musicians willingly appeared with the College orchestra, including Joseph Joachim and Hans Richter. Manns, Eugène Ysaÿe and Bernard Shaw praised it strongly. The historian David Wright says of Grove's legacy: "The founding of the RCM in 1883 clearly represents the major turning point for musical training in Britain. The new attitudes it espoused stemmed directly from the professionalizing ethos that modernized and transformed Victorian society."

Retirement and last years
Grove retired at Christmas 1894, when he was succeeded by Parry. By this time, a new building had been constructed for the college. Grove was elected an International Member of the American Philosophical Society in 1895. In 1896 Grove's Beethoven and his Nine Symphonies, "addressed to the amateurs of this country", appeared.

Early in 1899, Grove's health began to fail, and he died, aged 79, on 28 May 1900, in the house at Sydenham in which he had lived for nearly 40 years. He was buried in Ladywell and Brockley Cemetery.

title: George Grove


text:
St. George Jackson Mivart

St. George Jackson Mivart (30 November 1827 – 1 April 1900) was an English biologist. He is famous for starting as an ardent believer in natural selection and later becoming one of its fiercest critics. Mivart attempted to reconcile the theory of evolution as propounded by Charles Darwin with the beliefs of the Catholic Church but was condemned by both Darwin and the Church. His belief in a soul created by God and insistence that evolutionism was not incompatible with the existence of such a God brought him into conflict with other evolutionists, while his theological theories on hell and on the compatibility between science and Catholicism led him to clash with the Church.

Early life
Mivart was born in London. His parents were Evangelicals, and his father was the wealthy owner of Mivart's Hotel (now Claridge's). His education started at the Clapham Grammar School, and continued at Harrow School and King's College London. Following his conversion to Catholicism, he was instructed at St. Mary's, Oscott (1844–1846), and was confirmed there on 11 May 1845. His conversion automatically excluded him from the University of Oxford, then open only to members of the Anglican faith. His mother followed him into the Catholic Church in 1846.

Appointments
In 1851 he was called to the bar at Lincoln's Inn, but he devoted himself to medical and biological studies. In 1862 he was appointed to the chair in zoology at St. Mary's Hospital medical school. In 1869 he became a fellow of the Zoological Society of London, and in 1874 he was appointed by Mgr Capel as Professor of Biology at the short-lived Catholic University College, Kensington, a post he held until 1877.

He was vice-president of the Zoological Society twice (1869 and 1882); Fellow of the Linnean Society from 1862, secretary from 1874 to 1880, and vice-president in 1892. In 1867 he was elected a Fellow of the Royal Society for his work "On the Appendicular skeleton of the Primates". This work was communicated to the society by Thomas Henry Huxley. Mivart was a member of the Metaphysical Society from 1874. He received the degrees of Doctor of Philosophy from Pope Pius IX in 1876, and of Doctor of Medicine from the University of Louvain in 1884.

Mivart and Huxley
Mivart met Huxley in 1859, and was initially a close follower and a believer in natural selection. "Even as a professor he continued to attending Huxley's lectures ... they became close friends, dining together and arranging family visits." However, Huxley was always strongly anti-Catholic, and no doubt this attitude led to Mivart becoming disenchanted with him. Once disenchanted, he lost little time in reversing on the subject of natural selection. In short, he now believed that a higher teleology was compatible with evolution. "As to 'natural selection', I accepted it completely and in fact my doubts & difficulties were first excited by attending Prof. Huxley's lectures at the School of Mines."

Mivart's alternative evolutionism
Even before Mivart's publication of On the Genesis of Species in 1871, he had published his new ideas in various periodicals. Huxley, Lankester, and Flower had come out against his ideas, although O'Leary (2007) reports that "their initial reaction to Genesis of Species was tolerant and impersonal".

Though admitting evolution in general, Mivart denied its applicability to the human intellect (a view also taken by Wallace). His views as to the relationship between human nature and intellect and animal nature in general were given in his books Nature and Thought and Origin of Human Reason.

Mivart was someone Darwin took seriously; Darwin prepared a point-by-point refutation which appeared in the sixth edition of Origin of Species. One of Mivart's criticisms to which Darwin responded was a perceived failure of natural selection to explain the incipient stages of useful structures. Taking the eye as an example, Darwin was able to show many stages of light sensitivity and eye development in the animal kingdom as proof of the utility of less-than-perfect sight (argument by intermediate stages). Another was the supposed inability of natural selection to explain cases of parallel evolution, to which Huxley responded that the effect of natural selection in places with the same environment would tend to be similar.

Mivart's hostile review of the Descent of Man in the Quarterly Review aroused fury from his former intimates, including Darwin himself, who described it as "grossly unfair". Mivart had quoted Darwin by shortening sentences and omitting words, causing Darwin to write: "Though he means to be honourable, he is so bigoted that he cannot act fairly." Relationships between the two men were near breaking point. In response, Darwin arranged for the reprinting of a pamphlet by Chauncey Wright, previously issued in the US, which severely criticised Genesis of Species. Wright had, under Darwin's guidance, clarified what was, and was not, "Darwinism".

The quarrel reached a climax when Mivart lost his usual composure over what should have been a minor incident: In 1873, George Darwin (Charles' son) published a short article in The Contemporary Review suggesting that divorce should be made easier in cases of cruelty, abuse, or mental disorder. Mivart reacted with horror, using phrases like "hideous sexual criminality" and "unrestrained licentiousness". Huxley wrote a counter-attack, and both Huxley and Darwin broke off connections with Mivart. Huxley blackballed Mivart's attempt to join the Athenaeum Club.

Mivart's banned theological articles
In 1892 and 1893 Mivart published three articles on "Happiness in Hell" in the journal Nineteenth Century. Mivart proposed that the punishments of hell were not eternal, and that hell is compatible with some kind of happiness.

These articles were placed on the Index Expurgatorius. This was the first official action of the Catholic Church against Mivart but it "had nothing to do either with evolution or science." Later articles in January 1900 ("The Continuity of Catholicism" and "Scripture and Roman Catholicism" in The Nineteenth Century, and "Some Recent Catholic Apologists" in The Fortnightly Review) led to his being placed under interdict by Cardinal Vaughan. These last articles were written, by Mivart's own admission, in a provocative tone so that the authorities would have to act. In them, reversing his previous stance, he challenged the authority of the Church, concluding that the Bible and Catholic doctrine could not be reconciled with science.
 * "Without attempting to pass judgment on Mivart’s final stance, we can say that his attitude was not solely or principally determined by scientific motives and, more concretely, that evolution did not occupy a determining role in it."

The report of the consultor of the Holy Office dealing with Mivart's case significantly does not mention evolution.

Death
Mivart died of diabetes in London on 1 April 1900. His late heterodox opinions were a bar to his burial in consecrated ground. However, Sir William Broadbent gave medical testimony that these could be explained by the gravity and nature of the diabetes from which he had suffered.

After his death, a long final struggle took place between his friends and the church authorities. On 6 April 1900, his remains were deposited in catacomb Z beneath the Dissenters' Chapel, in the unconsecrated ground of the dissenters' section of the General Cemetery of All Souls, Kensal Green, in a public vault reserved for 'temporary deposits' (most of which were destined for repatriation to mainland Europe or the Americas). His remains were finally transferred to St. Mary's Roman Catholic Cemetery, Kensal Green, on 16 January 1904, for burial there on 18 January 1904.

Legacy
Mivart's name is commemorated in the scientific name of a species of lizard, Emoia mivarti.

Chief works

 * On the Genesis of Species, Macmillan & Co., 1871.
 * An Examination of Mr. Herbert Spencer's Psychology (Dublin 1874–80).
 * Lessons in Elementary Anatomy, 1873.
 * The Common Frog, Macmillan and Co., 1874 [1st Pub. in Nature Series, 1873].
 * Man and Apes: An Exposition of Structural Resemblances and Differences Bearing upon Questions of Affinity and Origin. London: Robert Hardwicke, 1873.
 * "One Point of Controversy with the Agnostics," in Manning, ed. Essays on Religion and Literature, Third Series, Longmans, Green & Co., 1874.
 * Lessons from Nature, 1876.
 * Contemporary Evolution, Henry S. King & Co., 1876.
 * Address to the Biological Section of the British Association, 1879.
 * The Cat: An Introduction to the Study of Backboned Animals, Especially Mammals, John Murray, 1881.
 * Nature and Thought: An Introduction to a Natural Philosophy, Kegan Paul, Trench & Co., 1882.
 * A Philosophical Catechism, 1884.
 * On Truth: A Systematic Inquiry, Kegan Paul, Trench & Co., 1889.
 * The Origin of Human Reason, Being an Examination of Recent Hypotheses Concerning it, Kegan Paul, Trench & Co., 1889.
 * Dogs, Jackals, Wolves and Foxes: Monograph of the Canidæ, Taylor & Francis, for R.H. Porter and Dulau & Co., 1890.
 * Introduction Générale à l'Etude de la Nature: Cours Professé à l'Université de Louvain, Louvain and Paris, 1891.
 * Birds: The Elements of Ornithology, Taylor & Francis, 1892.
 * Essays and Criticisms, Vol. 2, 1892.
 * Types of Animal Life, 1893.
 * Introduction to the Elements of Science. Boston: Little, Brown and Company, 1894.
 * The Helpful Science, Harper & Brothers, 1895.
 * Castle and Manor, 1900.
 * A Monograph of the Lories, or Brush-tongued Parrots, H. R. Porter, 1896.
 * The Groundwork of Science: A Study of Epistemology, John Murray, 1898.

Miscellany

 * Under the Ban: A Correspondence between Dr. St. George Mivart and Herbert Cardinal Vaughan. New York: Tucker Publishing Co., 1900.

Selected articles

 * "Difficulties of the Theory of Natural Selection," Part II, Part III, The Month, Vol. XI, 1869.
 * "On the Use of the Term 'Homology'," The Annals and Magazine of Natural History, No. 32, 1870.
 * "Evolution and its Consequences – A Reply to Professor Huxley," The Contemporary Review, Vol. XIX, 1872.
 * "Contemporary Evolution," Part II, Part III, The Contemporary Review, Vols. XXII/XXIII, 1873/1874.
 * "Instinct and Reason," The Contemporary Review, Vol. XXV, 1875.
 * "Likenesses: or Philosophical Anatomy," The Contemporary Review, Vol. XXVI, 1875.
 * "Natural History of the Kangaroo," Popular Science Monthly, Vol. VIII, 1876.
 * "What are Bats?," Popular Science Monthly, Vol. IX, 1876.
 * "Liberty of Conscience," The Dublin Review, Vol. XXVII, 1876.
 * "Emotion," The American Catholic Quarterly Review, Vol. III, 1878.
 * "The Meaning of Life," The Nineteenth Century, Vol. V, 1879.
 * "The Government of Life," The Nineteenth Century, Vol. V, 1879.
 * "On the Study of Natural History," The Contemporary Review, Vol. XXXV, 1879.
 * "What are Living Beings?," The Contemporary Review, Vol. XXXV, 1879.
 * "Animals and Plants," The Contemporary Review, Vol. XXXVI, 1879.
 * "The Forms and Colours of Living Creatures," The Contemporary Review, Vol. XXXVI, 1879.
 * "The Relation of Animals and Plants to Time," The Contemporary Review, Vol. XXXVII, 1880.
 * "The Geography of Living Creatures," The Contemporary Review, Vol. XXXVII, 1880.
 * "The Relation of Living Beings to One Another," The Contemporary Review, Vol. XXXVII, 1880.
 * "Notes on Spain," Part II, Part III, The American Catholic Quarterly Review, Vol. V, 1880.
 * "The Soul and Evolution," The American Catholic Quarterly Review, Vol. VI, 1881.
 * "A Limit to Evolution," The American Catholic Quarterly Review, Vol. VIII, 1883.
 * "On Catholic Politics," The Dublin Review, Vol. XCIII, 1883.
 * "The Life and Times of Frederic II," Part II, Part III, The American Catholic Quarterly Review, Vol. IX, 1884.
 * "Phases of Faith and Unfaith," The Catholic World, Vol. XXXIX, 1884.
 * "Ecclesiastical Survivals and Revivals," The Catholic World, Vol. XL, 1885.
 * "Organic Nature's Riddle," Part II, The Eclectic Magazine, Vol. XLI, 1885.
 * "Modern Catholics and Scientific Freedom," The Nineteenth Century, Vol. XVIII, 1885.
 * "A Tour in Catholic Teutonia," Part II, The Catholic World, Vol. XLII, 1886.
 * "What Are Animals and Plants?," The American Catholic Quarterly Review, Vol. XI, 1886.
 * "Notes on Colonial Zoology," The Contemporary Review, Vol. LI, 1887.
 * "The Catholic Church and Biblical Criticism," The Nineteenth Century, Vol. XXII, 1887.
 * "Catholicity and Reason," The Nineteenth Century, Vol. XXII, 1887.
 * "The Future of Christianity," The Forum, Vol. III, 1887.
 * "Laughter," The Forum, Vol. III, 1887.
 * "On the Possibly Dual Origin of the Mammalia," Proceedings of the Royal Society of London, Vol. XLIII, 1888.
 * "Why Tastes Differ," The American Catholic Quarterly Review, Vol. XIII, 1888.
 * "Impressions of Life in Vienna," The American Catholic Quarterly Review, Vol. XIII, 1888.
 * "Sins of Belief and Sins of Unbelief," The Nineteenth Century, Vol. XXIV, 1888.
 * "Darwin's Brilliant Fallacy," The Forum, Vol. VII, 1889.
 * "Where Darwinism Fails," The Forum, Vol. VII, 1889.
 * "Professing Themselves to be Wise, They Become Fools," The American Catholic Quarterly Review, Vol. XVI, 1891.
 * "The Foundations of Science," Natural Science, Vol. I, No. 7, 1892.
 * "Happiness in Hell," The Nineteenth Century, Vol. XXXII, 1892.
 * "Catholicity in England Fifty Years Ago—A Retrospect," Part II, Part III, The American Catholic Quarterly Review, Vol. XVII/XVIII, 1892/1893.
 * "Evolution in Professor Huxley," The Nineteenth Century, Vol. XXXIV, 1893.
 * "Christianity and Paganism," The Nineteenth Century, Vol. XXXIV, 1893.
 * "The Index and my Articles on Hell," The Nineteenth Century, Vol. XXXIV, 1893.
 * "L'Ancien Régime," Part II, The American Catholic Quarterly Review, Vol. XVII/XVIII, 1893/1894.
 * "The Newest Darwinism," The American Catholic Quarterly Review, Vol. XIX, No. 76, 1894.
 * "The Evolution of Evolution," The American Catholic Quarterly Review, Vol. XX, 1895.
 * "Balfour's Philosophy. Part I.: Some Consequences of Belief," The American Catholic Quarterly Review, Vol. XXI, 1896.
 * "Balfour's Philosophy. Part II.: Some Reasons for Belief," The American Catholic Quarterly Review, Vol. XXI, 1896.
 * "What Makes a Species?," The American Catholic Quarterly Review, Vol. XXIII, 1898.
 * "Living Nature," The American Catholic Quarterly Review, Vol. XXIII, 1898.
 * "The Continuity of Catholicism," The Nineteenth Century, Vol. XLVII, 1900.
 * "Scripture and Roman Catholicism," The Nineteenth Century, Vol. XLVII, 1900.

title: St. George Jackson Mivart


text:
Piru (spirit)

A piru is a fiend or demon in Finnish mythology. It was borrowed from Slavic mythology and was the counterpart of Perun, Slavic thunder god. However, piru lost its original meaning and refers to only demon in Finnish mythology.

In folklore, a piru is often featured as a nasty spirit of the forest with which a smart aleck either wins or loses a battle of wits, giving or receiving a forfeit in return. In many cases, poltergeist and haunting phenomena are described as "pirus". The Devil may be referred to as (proper noun) Piru, or Pääpiru, the main piru.

"Piru" is also a mild swearword in Finnish.

title: Piru (spirit)


text:
Herbert Vaughan

Herbert Alfred Henry Joseph Thomas Vaughan (15 April 1832 – 19 June 1903) was an English prelate of the Catholic Church. He served as Archbishop of Westminster from 1892 until his death in 1903, and was elevated to the cardinalate in 1893. He was the founder in 1866 of St Joseph's Foreign Missionary Society, known best as the Mill Hill Missionaries. He also founded the Catholic Truth Society and St. Bede's College, Manchester. As Archbishop of Westminster, he led the capital campaign and construction of Westminster Cathedral.

In 1871 Vaughan sent a group of Mill Hill priests to the United States to minister to freedmen. In 1893, the American branch of the society spun off, with Vaughan's permission, to form the Society of St Joseph of the Sacred Heart, whose members are known as Josephites.

Early life and education
Herbert Vaughan was born at Gloucester, the eldest son of Lieutenant-Colonel John Francis Vaughan, of an old recusant (Catholic) family, the Vaughans of Courtfield, Herefordshire. His mother, Eliza Rolls from The Hendre, Monmouthshire, was a Catholic convert and intensely religious. All five of the Vaughan daughters became nuns, while six of the eight sons received Holy Orders and became priests. Two were later called as bishops in addition to Herbert: Roger became Archbishop of Sydney, Australia and John became titular bishop of Sebastopolis and auxiliary bishop in Salford, England. A nephew, Francis, became Bishop of Menevia, Wales.

In 1841 Herbert, the eldest, went to study for six years at Stonyhurst College, then to the Jesuit school of Brugelette, Belgium (1846–1848), and then with the Benedictines at Downside Abbey, near Bath, England.

In 1851 Vaughan went to Rome, and studied for two years at the Collegio Romano, where for a time he shared lodgings with the poet, Aubrey Thomas de Vere. He became a friend and disciple of Henry Edward Manning. Manning, a Catholic convert, became the second Cardinal Archbishop of Westminster following the restoration of the Catholic hierarchy in Great Britain in 1850.

Career
Vaughan received Holy Orders at Lucca in 1854. On his return to England, he became Vice-President of St Edmund's College, at that time the chief seminary in the south of England for candidates for the priesthood. Since childhood, Vaughan had been filled with zeal for foreign missions. He convinced Cardinal Wiseman and the bishops to agree to a proposal to build a seminary in England that would train priests to serve on missions throughout the British Empire. With this goal, he made a fund-raising trip to America in 1863, from which he returned with £11,000.

In 1868, Vaughan became proprietor of The Tablet. He wrote James McMaster, owner of the New York Freeman's Journal and Catholic Register, "No one can appreciate more highly than I do the great mission of the Catholic press in these days of steam and universal education."

He succeeded in opening St Joseph's Foreign Missionary College, Mill Hill Park, London, in 1869. That same year, the Tenth Provincial Council of Baltimore passed a decree exhorting all bishops to establish missions and schools in their dioceses for African Americans. Subsequently, the Council Fathers wrote a letter requesting clergy for that purpose to Vaughan, superior general at Mill Hill. In 1871, Vaughan led a group of priests to the US to establish a mission society to minister to freedmen in the South.

In 1872 Vaughan was consecrated as the second Bishop of Salford, succeeding Bishop William Turner. Vaughan relinquished his position as superior at St. Joseph's College, but in 1876 established St Bede's College, conceived as a "commercial school" to prepare the sons of Manchester Catholics for a life in business and the professions. Vaughan chose to live at Hampton Grange, on the St. Bede's College campus, with his own Bishop's residence on Chapel Street in Salford being given over to a Seminary.

In 1879, as the most eminent local Catholic, Vaughan was chosen by the then Home Secretary, R.A. Cross, 1st Viscount Cross, to be one of the trustees of the £1,000 compensation paid to a Whalley Range farm labourer, William Habron, pardoned for the murder of PC Nicholas Cock. In 1892 Vaughan succeeded Manning as Archbishop of Westminster, receiving the cardinal's hat in 1893 as Cardinal-Priest of Santi Andrea e Gregorio al Monte Celio. Vaughan was a man of different type from his predecessor; he had none of the ultramontane Manning's intellectual finesse or his ardor for social reform. Vaughan did however have a more open attitude to women's enfranchisement, reported as saying, "I believe that the extension of the Parliamentary Franchise to women upon the same conditions as it is held by men would be a just and beneficial measure, tending to raise rather than to lower the course of national legislation." Vaughan was an ecclesiastic of remarkably fine presence and aristocratic leanings, intransigent in theological policy, and in personal character simply devout.

In 1893 the US Mill Hill mission, based in Baltimore, Maryland, reorganised with Vaughan's blessing as an independent institution, known as Society of St. Joseph of the Sacred Heart. Among its founders was the first African-American Catholic priest trained and ordained in the United States, Charles Uncles.

It was due to this theological "purity" that Vaughan assisted in scuttling an opportunity for rapprochement between Rome and the Church of England that was put into motion by a high-church Anglican, Charles Wood, 2nd Viscount Halifax and a French priest, Ferdinand Portal. Through the efforts of Vaughan and Archbishop of Canterbury Edward White Benson, this early form of ecumenism was put down. It culminated with the condemnation of Anglican Orders by Pope Leo XIII in his bull, Apostolicae curae.

It was Vaughan's most cherished ambition to see an adequate Westminster Cathedral. He worked untiringly to secure subscriptions for a capital campaign, with the result that the foundation stone for the cathedral was laid in 1895. When Vaughan died in 1903 at the age of 71, the building was so far complete that a Requiem Mass was said there. His body was interred at the cemetery of St. Joseph's College, the headquarters of the Mill Hill Missionaries in North London but it was moved back to the cathedral and reinterred in the Chapel of St Thomas of Canterbury (the "Vaughan Chantry") in 2005.

Founded

 * St. Joseph Foreign Missionary College, London, United Kingdom
 * St Bede's College
 * St. Joseph Society of the Sacred Heart, Baltimore, MD
 * Westminster Cathedral

Namesake

 * In 1914, the Cardinal Vaughan Memorial School was founded in his memory in Holland Park, London.

Published works

 * Vaughan, Herbert Cardinal, Archbishop of Westminster (1902). The Holy Sacrifice of the Mass (Fourth ed.). St. Louis, Missouri: B. Herder.

title: Herbert Vaughan


text:
Glass-ceramic

Glass-ceramics are polycrystalline materials produced through controlled crystallization of base glass, producing a fine uniform dispersion of crystals throughout the bulk material. Crystallization is accomplished by subjecting suitable glasses to a carefully regulated heat treatment schedule, resulting in the nucleation and growth of crystal phases. In many cases, the crystallization process can proceed to near completion, but in a small proportion of processes, the residual glass phase often remains.

Glass-ceramic materials share many properties with both glasses and ceramics. Glass-ceramics have an amorphous phase and one or more crystalline phases and are produced by a so-called "controlled crystallization" in contrast to a spontaneous crystallization, which is usually not wanted in glass manufacturing. Glass-ceramics have the fabrication advantage of glass, as well as special properties of ceramics. When used for sealing, some glass-ceramics do not require brazing but can withstand brazing temperatures up to 700 °C.

Glass-ceramics usually have between 30% [m/m] and 90% [m/m] crystallinity and yield an array of materials with interesting properties like zero porosity, high strength, toughness, translucency or opacity, pigmentation, opalescence, low or even negative thermal expansion, high temperature stability, fluorescence, machinability, ferromagnetism, resorbability or high chemical durability, biocompatibility, bioactivity, ion conductivity, superconductivity, isolation capabilities,  low dielectric constant and loss, corrosion resistance, high resistivity and break-down voltage. These properties can be tailored by controlling the base-glass composition and by controlled heat treatment/crystallization of base glass. In manufacturing, glass-ceramics are valued for having the strength of ceramic but the hermetic sealing properties of glass.

Glass-ceramics are mostly produced in two steps: First, a glass is formed by a glass-manufacturing process, after which the glass is cooled down. Second, the glass is put through a controlled heat treatment schedule. In this heat treatment the glass partly crystallizes. In most cases nucleation agents are added to the base composition of the glass-ceramic. These nucleation agents aid and control the crystallization process. Because there is usually no pressing and sintering, glass-ceramics have no pores, unlike sintered ceramics.

A wide variety of glass-ceramic systems exist, e.g., the Li2O × Al2O3 × nSiO2 system (LAS system), the MgO × Al2O3 × nSiO2 system (MAS system), and the ZnO × Al2O3 × nSiO2 system (ZAS system).

History
Réaumur, a French chemist, made early attempts to produce polycrystalline materials from glass, demonstrating that if glass bottles were packed into a mixture of sand and gypsum, and subjected to red heat for several days, the glass bottles turned opaque and porcelain-like. Although Réaumur was successful in the conversion of glass to a polycrystalline material, he was unsuccessful in achieving the control of the crystallization process, which is a key step in producing true practical glass ceramics with the improved properties mentioned above.

The discovery of glass-ceramics is credited to a man named Donald Stookey, a renowned glass scientist who worked at Corning Inc. for 47 years. The first iteration stemmed from a glass material, Fotoform, which was also discovered by Stookey while he was searching for a photo-etch-able material to be used in television screens. Soon after the beginning of Fotoform, the first ceramic material was discovered when Stookey overheated a Fotoform plate in a furnace at 900 degrees Celsius and found an opaque, milky-white plate inside the furnace rather than the molten mess that was expected. While examining the new material, which Stookey aptly named Fotoceram, he took note that it was much stronger than the Fotoform that it was created from as it survived a short fall onto concrete.

In the late 1950s two more glass-ceramic materials would be developed by Stookey, one found use as the radome in the nose cone of missiles, while the other led to the line of consumer kitchenware known as Corningware. Corning executives announced Stookey's discovery of the latter "new basic material" called Pyroceram which was touted as light, durable, capable of being an electrical insulator and yet thermally shock resistant. At the time, there were only few materials which offered the specific combination of characteristics that Pyroceram did and the material was rolled out as the Corningware kitchen line August 7, 1958.

Some of the success that Pyroceram brought inspired Corning to put an effort towards strengthening glass which became an effort by the technical director's of Corning titled Project Muscle. A lesser known "ultrastrong" glass-ceramic material developed in 1962 called Chemcor (now known as Gorilla Glass) was produced by Corning's glass team due to the Project Muscle effort. Chemcor would even be used to innovate the Pyroceram line of products as in 1961 Corning launched Centura Ware, a new line of Pyroceram that was lined with a glass laminate (invented by John MacDowell) and treated with the Chemcor process. Stookey continued to forge ahead in the discovery of the properties of glass-ceramics as he discovered how to make the material transparent in 1966. Though Corning would not release a product with his new innovation, for fear of cannibalizing Pyrex sales, until the late 1970s under the name Visions.

Nucleation and crystal growth
The key to engineering a glass-ceramic material is controlling the nucleation and growth of crystals in the base glass. The amount of crystallinity will vary depending on the amount of nuclei present and the time and temperature at which the material is heated. It is important to understand the types of nucleation occurring in the material, whether it is homogeneous or heterogeneous.

Homogeneous nucleation is a process resulting from the inherent thermodynamic instability of a glassy material. When enough thermal energy is applied to the system, the metastable glassy phase begins to return to the lower-energy, crystalline state. The term "homogeneous" is used here because the formation of nuclei comes from the base glass without any second phases or surfaces promoting their formation.

The rate of homogenous nucleation in a condensed system can be described with the following equation, proposed by Becker in 1938.

 * $$I\ =\ A \exp \left( -\frac{\Delta F^*+Q}{k_BT} \right)$$

Where Q is the activation energy for diffusion across the phase boundary, A is a constant, and $$F^*$$ is the maximum activation energy for formation of a stable nucleus, as given by the equation below.

 * $$\Delta F^* = \frac{16 \pi \Delta f_s ^3}{3\Delta f_v ^2}$$

Where $$\Delta f_v$$ is the change of free energy per unit volume resulting from the transformation from one phase to the other, and $$\Delta f_s$$ can be equated with interfacial tension.

Heterogeneous nucleation is a term used when a nucleating agent is introduced into the system to aid and control the crystallization process. The presence of this nucleating agent, in the form of an additional phase or surface, can act as a catalyst for nucleation and is particularly effective if there is epitaxy between the nucleus and the substrate. There are a number of metals that can act as nucleating agents in glass because they can exist in the glass in the form of particle dispersion of colloidal dimensions. Examples include copper, metallic silver, and platinum. It was suggested by Stookey in 1959 that the effectiveness of metallic nucleation catalysts relates to the similarities between the crystal structures of the metals and the phase being nucleated.

The most important feature of heterogenous nucleation is that the interfacial tension between the heterogeneity and the nucleated phase is minimized. This means that the influence that the catalyzing surface has on the rate of nucleation is determined by the contact angle at the interface. Based on this, Turnbull and Vonnegut (1952) modified the equation for homogenous nucleation rate to give an expression for heterogenous nucleation rate.

 * $$I_c\ =\ A^1 \exp \left( -\frac{\Delta F^*\ f(\theta)}{k_BT} \right)$$

If activation energy for diffusion is included, as suggested by Stokey (1959a), the equation then becomes:

 * $$I_c\ =\ A^1 \exp \left( -\frac{\Delta F^*\ f(\theta)+Q}{k_BT} \right)$$

From these equations, heterogeneous nucleation can be described in terms of the same parameters as homogeneous nucleation with a shape factor, which is a function of θ (contact angle). The term $$f(\theta)$$ is given by:

$$f(\theta)=\frac{(2+\cos\theta)(1-\cos\theta)^2}{4}$$

if the nucleus has the form of a spherical cap.

In addition to nucleation, crystal growth is also required for the formation of glass ceramics. The crystal growth process is of considerable importance in determining the morphology of the produced glass ceramic composite material. Crystal growth is primarily dependent on two factors. First, it is dependent upon the rate at which the disordered structure can be re-arranged into a periodic lattice with longer-range order. Second, it is dependent upon the rate at which energy is released in the phase transformation (essentially the rate of cooling at the interface).

Glass ceramics in medical applications
Glass-ceramics are used in medical applications due to their unique interaction, or lack thereof, with human body tissue. Bioceramics are typically placed into the following groups based on their biocompatibility: biopassive (bioinert), bioactive, or resorbable ceramics.

Biopassive (bioinert) ceramics are, as the name suggests, characterized by the limited interaction the material has with the surrounding biological tissue. Historically, these were the "first generation" biomaterials used as replacements for missing or damaged tissues. One problem resulting from using inert biomaterials was the body's reaction to the foreign object; it was found that a phenomenon known as "fibrous encapsulation" would occur, where tissues would grow around the implant in an attempt to isolate the object from the rest of the body. This occasionally caused a variety of problems such as necrosis or sequestration of the implant. Two commonly used bioinert materials are alumina (Al2O3) and zirconia (ZrO2). Bioactive materials have the ability to form bonds and interfaces with natural tissues. In the case of bone implants, two properties known as osteoconduction and osteoinduction play an important role in the success and longevity of the implant. Osteoconduction refers to a material's ability to permit bone growth on the surface and into the pores and channels of the material. Osteoinduction is a term used when a material stimulates existing cells to proliferate, causing new bone to grow independently of the implant. In general, the bioactivity of a material is a result of a chemical reaction, typically dissolution of the implanted material. Calcium phosphate ceramics and bioactive glasses are commonly used as bioactive materials as they exhibit this dissolution behavior when introduced to living body tissue. One engineering goal relating to these materials is that the dissolution rate of the implant be closely matched to the growth rate of new tissue, leading to a state of dynamic equilibrium.

Resorbable ceramics are similar to bioactive ceramics in their interaction with the body, but the main difference lies in the extent to which the dissolution occurs. Resorbable ceramics are intended to gradually dissolve entirely, all the while new tissue grows in its stead. The architecture of these materials has become quite complex, with foam-like scaffolds being introduced to maximize the interfacial area between the implant and body tissue. One issue that arises from using highly porous materials for bioactive/resorbable implants is the low mechanical strength, especially in load-bearing areas such as the bones in the legs. An example of a resorbable material that has seen some success is tricalcium phosphate (TCP), however, it too falls short in terms of mechanical strength when used in high-stress areas.

LAS system
The commercially most important system is the Li2O × Al2O3 × nSiO2 system (LAS system). The LAS system mainly refers to a mix of lithium, silicon, and aluminum oxides with additional components, e.g., glass-phase-forming agents such as Na2O, K2O and CaO and refining agents. As nucleation agents most commonly zirconium(IV) oxide in combination with titanium(IV) oxide is used. This important system was studied first and intensively by Hummel, and Smoke.

After crystallization the dominant crystal phase in this type of glass-ceramic is a high-quartz solid solution (HQ s.s.). If the glass-ceramic is subjected to a more intense heat treatment, this HQ s.s. transforms into a keatite-solid solution (K s.s., sometimes wrongly named as beta-spodumene). This transition is non-reversible and reconstructive, which means bonds in the crystal-lattice are broken and new arranged. However, these two crystal phases show a very similar structure as Li could show.

An interesting property of these glass-ceramics is their thermomechanical durability. Glass-ceramic from the LAS system is a mechanically strong material and can sustain repeated and quick temperature changes up to 800–1000 °C. The dominant crystalline phase of the LAS glass-ceramics, HQ s.s., has a strong negative coefficient of thermal expansion (CTE), keatite-solid solution as still a negative CTE but much higher than HQ s.s. These negative CTEs of the crystalline phase contrasts with the positive CTE of the residual glass. Adjusting the proportion of these phases offers a wide range of possible CTEs in the finished composite. Mostly for today's applications a low or even zero CTE is desired. Also a negative CTE is possible, which means, in contrast to most materials when heated up, such a glass-ceramic contracts. At a certain point, generally between 60% [m/m] and 80% [m/m] crystallinity, the two coefficients balance such that the glass-ceramic as a whole has a thermal expansion coefficient that is very close to zero. Also, when an interface between material will be subject to thermal fatigue, glass-ceramics can be adjusted to match the coefficient of the material they will be bonded to.

Originally developed for use in the mirrors and mirror mounts of astronomical telescopes, LAS glass-ceramics have become known and entered the domestic market through its use in glass-ceramic cooktops, as well as cookware and bakeware or as high-performance reflectors for digital projectors.

Ceramic matrix composites
One particularly notable use of glass-ceramics is in the processing of ceramic matrix composites. For many ceramic matrix composites typical sintering temperatures and times cannot be used, as the degradation and corrosion of the constituent fibres becomes more of an issue as temperature and sintering time increase. One example of this is SiC fibres, which can start to degrade via pyrolysis at temperatures above 1470K. One solution to this is to use the glassy form of the ceramic as the sintering feedstock rather than the ceramic, as unlike the ceramic the glass pellets have a softening point and will generally flow at much lower pressures and temperatures. This allows the use of less extreme processing parameters, making the production of many new technologically important fibre-matrix combinations by sintering possible.

Glass ceramics in cooktops
Glass-ceramic from the LAS-System is a mechanically strong material and can sustain repeated and quick temperature changes, and its smooth glass-like surface is easy to clean, therefore it is often used as a cooktop surface. The material has a very low heat conduction coefficient, which means that it stays cool outside the cooking area. It can be made nearly transparent (15–20% loss in a typical cooktop) for radiation in the infrared wavelengths. In the visible range glass-ceramics can be transparent, translucent or opaque and even colored by coloring agents.

However, glass-ceramic is not totally unbreakable. Because it is still a brittle material as glass and ceramics are, it can be broken - in particular it is less robust than traditional cooktops made of steel or cast iron. There have been instances where users reported damage to their cooktops when the surface was struck with a hard or blunt object (such as a can falling from above or other heavy items).

, there are two major types of electrical stoves with cooktops made of glass-ceramic:
 * A radiant heating stove uses coils or infrared halogen lamps as the heating elements. The surface of the glass-ceramic cooktop above the burner heats up, but the adjacent surface remains cool because of the low heat conduction coefficient of the material.
 * An induction stove heats a metal pot's bottom directly through electromagnetic induction.

This technology is not entirely new, as glass-ceramic ranges were first introduced in the 1970s using Corningware tops instead of the more durable material used today. These first generation smoothtops were problematic and could only be used with flat-bottomed cookware as the heating was primarily conductive rather than radiative.

Compared to conventional kitchen stoves, glass-ceramic cooktops are relatively simple to clean, due to their flat surface. However, glass-ceramic cooktops can be scratched very easily, so care must be taken not to slide the cooking pans over the surface. If food with a high sugar content (such as jam) spills, it should never be allowed to dry on the surface, otherwise damage will occur.

For best results and maximum heat transfer, all cookware should be flat-bottomed and matched to the same size as the burner zone.

Industry and material variations
Some well-known brands of glass-ceramics are Pyroceram, Ceran, Eurokera, Zerodur, and Macor. Nippon Electric Glass is a predominant worldwide manufacturer of glass ceramics, whose related products in this area include FireLite and NeoCeram, ceramic glass materials for architectural and high temperature applications respectively. Keralite, manufactured by Vetrotech Saint-Gobain, is a specialty glass-ceramic fire and impact safety rated material for use in fire-rated applications. Glass-ceramics manufactured in the Soviet Union/Russia are known under the name Sitall. Macor is a white, odorless, porcelain-like glass ceramic material and was developed originally to minimize heat transfer during crewed spaceflight by Corning Inc. StellaShine, launched in 2016 by Nippon Electric Glass Co., is a heat-resistant, glass-ceramic material with a thermal shock resistance of up to 800 degrees Celsius. This was developed as an addition to Nippon's line of heat-resistant cooking range plates along with materials like Neoceram. KangerTech is an ecigarette manufacturer which began in Shenzhen, China which produces glass ceramic materials and other special hardened-glass applications like vaporizer modification tanks.

The same class of material is also used in Visions and CorningWare glass-ceramic cookware, allowing it to be taken from the freezer directly to the stovetop or oven with no risk of thermal shock while maintaining the transparent look of glassware.

title: Glass-ceramic


text:
Talk:Glass-ceramic

Wiki Education Foundation-supported course assignment
This article was the subject of a Wiki Education Foundation-supported course assignment, between 25 August 2020 and 11 December 2020. Further details are available on the course page. Student editor(s): Crook47, Demxr2. Peer reviewers: SRMcGarvey, Racrz8.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 22:26, 16 January 2022 (UTC)

Untitled
Info from the de:-Wikipedia. I'm not an expert on glass-ceramic and I am confused a bit: if glass-ceramic has such a low heat conduction coefficient, why does the plate get hot at all? Is it the infrared radiation heating the pot, which then heats the surface? How does this thing work? Lupo 12:15, 28 Jun 2004 (UTC)

heat conduction coefficient means how much heat the material transmits by conduction; metals tend to have high coefficients (100's of W/m/K) while glass and ceramics have low ones (SiO2 ceramic has 1.04 W/m/K at 200 deg C). Low doesn't mean zero, so the material does transmit slightly, but I would guess (no expert) a lot of the heating occurs by absorption of the infra red radiation by the ceramic just above the heating elements. This is because there must be some infra red absorption (about 15% from the CERAN article).

The German CERAN article says CERAN Platten haben eine hohe Hitzedurchlässigkeit und praktisch keine Wärmeausdehnung. which says that they have a high heat transmission ability (not the same as conductance) and practically no heat expansion. -Wikibob | Talk 21:48, 2004 Oct 5 (UTC)

 * So you're saying that the plate gets hot because of this 15-20% absorbtion of infrared radiation emitted by the burner? Plus maybe by the hot pot above? And the pot itself is heated primarily by the other 80-85% going through the glass-ceramic? Hmmm... the plates get really hot, even if there is no pot on them. (In the first type, using a burner, not in an induction stove.) Time to e-mail Schott? Lupo 07:54, 6 Oct 2004 (UTC)

Why does the glass plate heat up?
The original question was: "If glass-ceramic has such a low heat conduction coefficient, why does the plate get hot at all?"
 * The plate heats up because the conduction coefficient is not zero, as stated above. If you put a hot object on top of the plate, the plate would eventually heat up. A low conduction coefficient just means that it would take a long time for it to heat up. This is a good thing - you want the pot to heat up, not the stove itself. There's no point to heat up the stove surface because it would just be a waste of energy.

So, this leads us to the next question: "Is it the infrared radiation heating the pot, which then heats the surface?"
 * Yes, this is the primary reason why the glass plate heats up. It also heats up because of the infared radiation. However, this contribution is constructed so that it is less. The stove is manufactured so that most of the infared radiation heats the pot, and not the stove surface!

 * All right. Then see my follow-up remark: the plate also gets really hot (didn't measure it, but I sure don't want to touch it!) when there's no pot on the plate. That must then come from these 15-20% of infrared radiation that are absorbed, mustn't it? Or is it just an illusion? I mean, do I only think the plate got hot because when I put my hand above the plate and feel it's hot, my hand gets hit by the other 80-85% that do get through? Hmmm... I think I'll have to buy some kind of thermometer and try to measure the surface temperature of the stove right after switching a plate off, without ever having placed a pot on it. Lupo 08:05, 11 Jun 2005 (UTC)

Finally, the last question: "How does this thing work?"
 * Let's look a microwave oven first. If you placed a metal object in a microwave oven, and started the machine, the metal object would heat up - in fact, it would heat up quite a bit! The technology for stoves with induction coils is an application of this phenomena. Think of the stove as a sort of "open microwave". Hope this helps! --HappyCamper 02:19, 11 Jun 2005 (UTC)
 * Phenomena is plural!
 * Sorry, I don't get that analogy at all. The physics involved between a microwave oven and an induction stove are quite different, I thought. My question on "how does this thing work" was more a short-hand of saying "how does the heat get to the food, and wat heats up the plate". I wasn't asking about an induction stove; I can understand more or less how these work. Thanks for the answers! Lupo 08:05, 11 Jun 2005 (UTC)

Induction ranges & corningware: clearing up some confusion
Some day, I'll come back and add some info about Corningware, the best-known US brand of glass-ceramic materials. The article should also mention vaseline glass.

On to induction ranges: these actually work by hysteresis losses (the current article is wrong about this, btw), also a source of inefficiency in transformer cores. What ultimately heats the food is the energy dissipated when a ferromagnetic pot (austenitic stainless steel, copper, aluminum, and glass pans don't work on iduction ranges unless they're built with a ferritic steel insert) is magnetized in one direction, then the other, 50 to 60 times a second (usually 50 Hz, since they're more popular in Europe). If the coil heats up without any pot on it, chances are very good that your cooktop is of the type with halogen lamps or ohmic heating elements underneath, that work like an Easy-Bake Oven or a normal electric range, respectively. If it glows white, it's halogen; red (only on high heat), and it's a normal heating element that heats the ceramic by conduction. Keep in mind how much thinner a plate is top-to-bottom as opposed to side-to-side.--Joel 23:14, 17 Jun 2005 (UTC)

General remarks
Hi! Sorry, I am new at wikipedia and I just came across the glass-ceramic (gc) article, which is, I am afraid, in some parts quite wrong. However, I am not familiar enough with wiki (I will try to become :) to change it. But some general remarks: ß-spodumen is NOT the major phase in gc. (I suppose you are speaking of the LAS-System, which is only ONE gc system) Exactly speaking there is even no so called ß-spodumen but keatite solid solution. And this keatite s.s. is only existing in gc's which are translucent or opaque, which is the minor amount of gc's used today. For the LAS-System (Li-Al-Si) which is the most used one today, ß-Eucryptite is the major phase. This gc's are transparent and used in cooktops and telescopes, and projectors. If this gc is heated up above ca. 900°C for some time, the ß-Eucryptite changes to ß-keatite (or wrongly saying ß-spodumene). But in general, this phase transformation is NOT wanted (just in some special cases)

BUT also: There are many other Gc's systems which are e.g. MAS (Mg-Al-Si-System), Phlogopit, ZAs (Zn-...), Lithium-Disilikate, ...

There are some other points which are not really good, but I am afraid to change them. Any suggestions?

Best regards Lagodefroy (talk) 14:21, 24 June 2009 (UTC)

Changes to page
Hi all,

ok, nobody complained about my remarks about the errors, so now I wil try to correct the page step by step. As I said, I am new with wiki and unfortunetly I do not have so much time as I want to. Please lets discuss if there is anything you do not agree with!

I made a lot of changes and rewrote the article carefully. However, I am no native English speaker, so please advice here. In addition, the part about the stoves does not fit in my opinion, however I did not delete it. Please advice again.

Lagodefroy (talk) 14:39, 12 January 2010 (UTC)

I have reviewed the article again, and deleted the passage about "vaseline glass" as there is no evidence in the linked article that vaseline glass is a glass-ceramic (which I also doubt strongly). Lagodefroy (talk) 12:03, 27 January 2010 (UTC)

"so called nucleation agents"
Why "so called nucleation agents"? The wording seems to imply that the additives are not nucleation agents, although they are so called. Because if they were nucleation agents, they'd simply be called "nucleation agents", not "so-called nucleation agents". -- Wegesrand (talk) 14:32, 6 January 2011 (UTC)

yep, you're right. It should mean more like "additions which are called nucleation agents"... but I see that it is misleading. I deleted "so called". Lagodefroy (talk) 10:27, 28 January 2011 (UTC)lagodefroy

History of Glass Ceramics
I think a new section about the history of glass-ceramics would improve the quality of this page significantly. The initial discovery of glass-ceramics was an accident. Stanley Donald Stookey was performing an experiment in which his furnace malfunctioned and heated his glass sample to a much higher temperature than intended. He found that the resulting material had much different properties than the initial glass and the original ceramics that it was composed of. This discovery lead to the rapid development of CorningWare and other glass-ceramic materials in the following years. I don't have enough time right now to provide any citations, but I plan on doing so in the near future. --Demxr2 (talk) 16:40, 25 September 2020 (UTC)

I'm going to be bulking out this section specifically with a few short paragraphs on Stookey's discovery of the material and some of the development as time went on. My work on this is still slightly incomplete and I'll be continuing to make slight edits as I find sources to justify those changes. -- Crook47 (talk) 17:27, 6 November 2020 (UTC) Crook47 Crook47 (talk) 17:27, 6 November 2020 (UTC)

Adding New Sections
I am going to add new sections on the Nucleation and Growth processes and also Medical Applications of Glass-Ceramics because both of these are extremely relevant to the topics. Demxr2 (talk) 17:21, 6 November 2020 (UTC)

New cooktop photo
Hi all, I have uploaded a new photo of a glass-ceramic cooktop. I would like to suggest that we could use it to replace the current photo, which is almost 20 years old. Let me know what you think! Elisabeth at SCHOTT (talk) 11:55, 18 April 2024 (UTC)

 * I've updated the photo in the article. Hope that works for you all! Elisabeth at SCHOTT (talk) 09:37, 4 June 2024 (UTC)

title: Talk:Glass-ceramic


text:
William Thomson (bishop)

William Thomson, (11 February 1819 – 25 December 1890) was an English church leader, Archbishop of York from 1862 until his death.

Early life
He was born the eldest son of John Thompson [sic] of Kelswick House, near Whitehaven, Cumberland, and educated at Shrewsbury School and at The Queen's College, Oxford, of which he became a scholar. He took his B.A. degree in 1840, and was soon afterwards made fellow of his college. He was ordained in 1842, and worked as a curate at Cuddesdon. In 1847 he was made tutor of his college, and in 1853 he delivered the Bampton lectures, his subject being The Atoning Work of Christ viewed in Relation to some Ancient Theories. These lectures established his reputation.

Career
Thomson's activity was not confined to theology. He was made fellow of the Royal Society and the Royal Geographical Society. He also wrote a very popular Outline of the Laws of Thought (1842). He sided with the party at Oxford which favoured university reform, but this did not prevent him from being appointed provost of his college in 1855. In 1858 he was made preacher at Lincoln's Inn and a volume of his sermons was published in 1861. In the same year he edited Aids to Faith, a volume written in opposition to Essays and Reviews, the progressive sentiments of which had stirred up controversy in the Church of England.

In December 1861 he became Bishop of Gloucester and Bristol, and within a year he was elevated to Archbishop of York. In this position his moderate orthodoxy led him to join Archbishop Archibald Campbell Tait in supporting the Public Worship Regulation Act, and, as president of the northern convocation, he came frequently into sharp collision with the lower house of that body. But if he thus incurred the hostility of the High Church party among the clergy, he was admired by the laity for his strong sense, his clear and forcible reasoning, and his wide knowledge, and he remained to the last a power in the north of England. In his later years he published an address read before the members of the Royal Society of Edinburgh (1868), one on Design in Nature, for the Christian Evidence Society, which reached a fifth edition, various charges and pastoral addresses, and he was one of the projectors of the Speaker's Commentary, for which he wrote the "Introduction to the Synoptic Gospels."

See the Quarterly Review (April 1892).

Family
His parents were John Thompson (sic, 1791–1878) and Isabella Thompson (–1847) On 24 July 1855 in Oxford, Thomson married Zoë Skene daughter of James Henry Skene (1812–), British Consul at Aleppo.

They had the following children:
 * Ethel Zoë Thomson (1856–), who later edited Thomson's Life and Letters.
 * Wilfred Forbes Home Thomson (1858–1939)
 * Jocelyn Home Thomson (1859–1908)
 * Sir Basil Home Thomson, KCB (21 April 1861 – 26 March 1939), a British intelligence officer, police officer, prison governor, colonial administrator, and writer
 * Zoë Jane Thomson (1862–)
 * Beatrice Mary Thomson (1864–)
 * Alexandra Thomson (1867–1907). Married Col. John Studholme (10 February 1863 – 26 May 1934)
 * Madeline Ita Mary Thomson (1880–)
 * Bernard Henry Home Thomson (1874–1924), his granddaughter is the author Rose Tremain, and his great grandchildren are Rachael Daniel, Tamsin Daniel, Cléon Daniel, and Sebastian Daniel.

title: William Thomson (bishop)