Colonel
Colonel (abbreviated as Col., Col or COL) is a senior military officer rank used in many countries. It is also used in some police forces and paramilitary organizations.
In the 17th, 18th and 19th centuries, a colonel was typically in charge ...
Sir George Everest
CB FRS FRAS FRGS (; 4 July 1790 – 1 December 1866) was a British surveyor and geographer who served as
Surveyor General of India
The Surveyor General of India is the Head of Department of Survey of India, A department under the Ministry of Science and Technology of Government of India. The Surveyor General is also the most senior member of the Survey of India Service, an o ...
from 1830 to 1843.
After receiving a military education in Marlow, Everest joined the
East India Company
The East India Company (EIC) was an English, and later British, joint-stock company founded in 1600 and dissolved in 1874. It was formed to trade in the Indian Ocean region, initially with the East Indies (the Indian subcontinent and Sou ...
and arrived in India at the age of 16. He was eventually made an assistant to
William Lambton
Lieutenant-Colonel William Lambton, FRS (c. 1753 – 20 or 26 January 1823) was a British soldier, surveyor, and geographer who began a triangulation survey in 1800-1802 that was later called the Great Trigonometrical Survey of India. His init ...
on the
Great Trigonometric Survey
The Great Trigonometrical Survey was a project that aimed to survey the entire Indian subcontinent with scientific precision. It was begun in 1802 by the British infantry officer William Lambton, under the auspices of the East India Company.G ...
, and replaced Lambton as superintendent of the survey in 1823. Everest was largely responsible for surveying the
meridian arc
In geodesy and navigation, a meridian arc is the curve between two points on the Earth's surface having the same longitude. The term may refer either to a segment of the meridian, or to its length.
The purpose of measuring meridian arcs is to ...
from the southernmost point of India north to
Nepal
Nepal (; ne, नेपाल ), formerly the Federal Democratic Republic of Nepal ( ne,
सङ्घीय लोकतान्त्रिक गणतन्त्र नेपाल ), is a landlocked country in South Asia. It is ma ...
, a distance of about , a task that took from 1806 to 1841 to complete. He was made Surveyor General of India in 1830, retiring in 1843 and returning to England.
In 1865, the
Royal Geographical Society
The Royal Geographical Society (with the Institute of British Geographers), often shortened to RGS, is a learned society and professional body for geography based in the United Kingdom. Founded in 1830 for the advancement of geographical scien ...
renamed Peak XV – at the time only recently identified as the world's highest peak – to
Mount Everest
Mount Everest (; Tibetan: ''Chomolungma'' ; ) is Earth's highest mountain above sea level, located in the Mahalangur Himal sub-range of the Himalayas. The China–Nepal border runs across its summit point. Its elevation (snow hei ...
in his honour.
Andrew Scott Waugh, his protégé and successor as surveyor general, had been responsible for putting his name forward in 1856. Everest's name was used as a compromise due to the difficulty of choosing between multiple local names for the mountain. He initially objected to the honour, as he had had nothing to do with its discovery and believed his name was not easily written or pronounced in
Hindi
Hindi (Devanāgarī: or , ), or more precisely Modern Standard Hindi (Devanagari: ), is an Indo-Aryan language spoken chiefly in the Hindi Belt region encompassing parts of northern, central, eastern, and western India. Hindi has been ...
.
Sir George's surname is pronounced ("EEV-rist").
Biography
Everest was born on 4 July 1790, but his birthplace is uncertain.
["George Everest was born on 4 July 1790 but the location is open to doubt. This uncertainty as to his birthplace arises because his father William Tristram Everest had an estate near Crickhowell in south ]Wales
Wales ( cy, Cymru ) is a country that is part of the United Kingdom. It is bordered by England to the east, the Irish Sea to the north and west, the Celtic Sea to the south west and the Bristol Channel to the south. It had a population in ...
and some reference works suggest he was born there. ..George's baptismal certificate certainly indicates that he was baptized in Greenwich but although the certificate also bears his date of birth it does not indicate the locality." He was baptised at
St Alfege Church,
Greenwich
Greenwich ( , ,) is a town in south-east London, England, within the ceremonial county of Greater London. It is situated east-southeast of Charing Cross.
Greenwich is notable for its maritime history and for giving its name to the Greenwich ...
, London, on 27 January 1791. He was born either at Greenwich or at Gwernvale Manor, his family's estate near
Crickhowell
Crickhowell (; cy, Crucywel , non-standard spelling ') is a town and community in southeastern Powys, Wales, near Abergavenny, and is in the historic county of Brecknockshire.
Location
The town lies on the River Usk, on the southern edge ...
,
Brecknockshire
, image_flag=
, HQ= Brecon
, Government= Brecknockshire County Council (1889-1974)
, Origin= Brycheiniog
, Status=
, Start= 1535
, End= ...
(now part of
Powys
Powys (; ) is a county and preserved county in Wales. It is named after the Kingdom of Powys which was a Welsh successor state, petty kingdom and principality that emerged during the Middle Ages following the end of Roman rule in Britain.
Geog ...
),
Wales
Wales ( cy, Cymru ) is a country that is part of the United Kingdom. It is bordered by England to the east, the Irish Sea to the north and west, the Celtic Sea to the south west and the Bristol Channel to the south. It had a population in ...
. Everest was the eldest son and third of six children born to Lucetta Mary (née Smith) and William Tristram Everest. His father was a solicitor and
justice of the peace
A justice of the peace (JP) is a judicial officer of a lower or '' puisne'' court, elected or appointed by means of a commission ( letters patent) to keep the peace. In past centuries the term commissioner of the peace was often used with the s ...
, part of a "Greenwich family of long standing", and was successful enough to acquire a large estate in
south Wales
South Wales ( cy, De Cymru) is a loosely defined region of Wales bordered by England to the east and mid Wales to the north. Generally considered to include the historic counties of Glamorgan and Monmouthshire, south Wales extends westwards ...
. His grandfather John Everest, the son of a butcher, was the first in the family to enter the legal profession. The Everest family in Greenwich can be traced at least as far back as the late 1600s, when Tristram Everest – John's great-grandfather – was a butcher in Church Street.
[
Everest was educated at the Royal Military College (Cadet Branch) in ]Marlow, Buckinghamshire
Marlow (; historically Great Marlow or Chipping Marlow) is a town and civil parish within the Unitary Authority of Buckinghamshire, England. It is located on the River Thames, south-southwest of High Wycombe, west-northwest of Maidenhead and ...
, before joining the East India Company
The East India Company (EIC) was an English, and later British, joint-stock company founded in 1600 and dissolved in 1874. It was formed to trade in the Indian Ocean region, initially with the East Indies (the Indian subcontinent and Sou ...
as a cadet in 1806. He was commissioned as a second lieutenant
Second lieutenant is a junior commissioned officer military rank in many armed forces, comparable to NATO OF-1 rank.
Australia
The rank of second lieutenant existed in the military forces of the Australian colonies and Australian Army unt ...
in the Bengal Artillery
The Bengal Army was the army of the Bengal Presidency, one of the three presidencies of British India within the British Empire.
The presidency armies, like the presidencies themselves, belonged to the East India Company (EIC) until the Govern ...
, and sailed for India the same year.[
]
Everest was a Freemason
Freemasonry or Masonry refers to fraternal organisations that trace their origins to the local guilds of stonemasons that, from the end of the 13th century, regulated the qualifications of stonemasons and their interaction with authorities ...
, initiated (date unknown) in Neptune Lodge, Penang, under the authority of the United Grand Lodge of England
The United Grand Lodge of England (UGLE) is the governing Masonic lodge for the majority of freemasons in England, Wales and the Commonwealth of Nations. Claiming descent from the Masonic grand lodge formed 24 June 1717 at the Goose & Gridiron ...
. Later, having returned to England, he joined Prince of Wales's Lodge, London, on 20 February 1829.
Early career in India
Little is known about Everest's earliest years in India, but he apparently had a talent for mathematics and astronomy. He was seconded to Java
Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's mo ...
in 1814, where Lieutenant-Governor Stamford Raffles
Sir Thomas Stamford Bingley Raffles (5 July 1781 – 5 July 1826) was a British statesman who served as the Lieutenant-Governor of the Dutch East Indies between 1811 and 1816, and Lieutenant-Governor of Bencoolen between 1818 and 1824. He is ...
appointed him to survey the island. He returned to Bengal in 1816, where he improved British knowledge of the Ganges
The Ganges ( ) (in India: Ganga ( ); in Bangladesh: Padma ( )). "The Ganges Basin, known in India as the Ganga and in Bangladesh as the Padma, is an international river to which India, Bangladesh, Nepal and China are the riparian states." is ...
and the Hooghly. He later surveyed a semaphore
Semaphore (; ) is the use of an apparatus to create a visual signal transmitted over distance. A semaphore can be performed with devices including: fire, lights, flags, sunlight, and moving arms. Semaphores can be used for telegraphy when arr ...
line from Calcutta
Kolkata (, or , ; also known as Calcutta , the official name until 2001) is the capital of the Indian state of West Bengal, on the eastern bank of the Hooghly River west of the border with Bangladesh. It is the primary business, commer ...
to Benares
Varanasi (; ; also Banaras or Benares (; ), and Kashi.) is a city on the Ganges river in northern India that has a central place in the traditions of pilgrimage, death, and mourning in the Hindu world.
*
*
*
* The city has a syncretic tra ...
, covering approximately . Everest's work came to the attention of Colonel William Lambton
Lieutenant-Colonel William Lambton, FRS (c. 1753 – 20 or 26 January 1823) was a British soldier, surveyor, and geographer who began a triangulation survey in 1800-1802 that was later called the Great Trigonometrical Survey of India. His init ...
, the leader of the Great Trigonometrical Survey
The Great Trigonometrical Survey was a project that aimed to survey the entire Indian subcontinent with scientific precision. It was begun in 1802 by the British infantry officer William Lambton, under the auspices of the East India Company.Gi ...
(GTS), who appointed him as his chief assistant. He joined Lambton at Hyderabad
Hyderabad ( ; , ) is the capital and largest city of the Indian state of Telangana and the ''de jure'' capital of Andhra Pradesh. It occupies on the Deccan Plateau along the banks of the Musi River, in the northern part of Southern Indi ...
in 1818, where he was in the process of surveying a meridian arc
In geodesy and navigation, a meridian arc is the curve between two points on the Earth's surface having the same longitude. The term may refer either to a segment of the meridian, or to its length.
The purpose of measuring meridian arcs is to ...
northward from Cape Commorin. He was responsible for much of the fieldwork, and in 1820 contracted malaria
Malaria is a mosquito-borne infectious disease that affects humans and other animals. Malaria causes symptoms that typically include fever, tiredness, vomiting, and headaches. In severe cases, it can cause jaundice, seizures, coma, or death. ...
, necessitating a period of recovery spent at the Cape of Good Hope
The Cape of Good Hope ( af, Kaap die Goeie Hoop ) ;''Kaap'' in isolation: pt, Cabo da Boa Esperança is a rocky headland on the Atlantic coast of the Cape Peninsula in South Africa.
A common misconception is that the Cape of Good Hope is ...
.[
Everest returned to India in 1821. He succeeded as superintendent of the GTS upon Lambton's death in 1823, and over the following years extended his predecessor's efforts on the arc up to ]Sironj
Sironj is a town and a municipality in Vidisha district in the Indian state of Madhya Pradesh
Madhya Pradesh (, ; meaning 'central province') is a state in central India. Its capital is Bhopal, and the largest city is Indore, with Jabalpur ...
, in present-day Madhya Pradesh
Madhya Pradesh (, ; meaning 'central province') is a state in central India. Its capital is Bhopal, and the largest city is Indore, with Jabalpur, Ujjain, Gwalior, Sagar, and Rewa being the other major cities. Madhya Pradesh is the second ...
. Everest suffered from poor health, however, and the effects of fever and rheumatism left him half paralysed. He left for England in 1825, where he spent the following five years recuperating. Everest was elected as a Fellow of the Royal Society
Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural knowledge, including mathemati ...
in March 1827. Most of his free time was spent lobbying the East India Company for better equipment and studying the methods used by the Ordnance Survey
Ordnance Survey (OS) is the national mapping agency for Great Britain. The agency's name indicates its original military purpose (see ordnance and surveying), which was to map Scotland in the wake of the Jacobite rising of 1745. There was a ...
; he frequently corresponded with Thomas Frederick Colby
Thomas Frederick Colby FRS FRSE FGS FRGS (1 September 17849 October 1852), was a British major-general and director of the Ordnance Survey (OS).
A Fellow of the Royal Astronomical Society and Royal Society, Colby was one of the leading geograp ...
.[
He became acquainted with Indian thought according to his niece Mary Boole:
It is very likely he introduced Indian thought to others as well:
]
Surveyor General of India
In June 1830, Everest returned to India to continue his work on the GTS, and was simultaneously appointed Surveyor General of India
The Surveyor General of India is the Head of Department of Survey of India, A department under the Ministry of Science and Technology of Government of India. The Surveyor General is also the most senior member of the Survey of India Service, an o ...
. The arc from Cape Commorin to the northern border of British India was finally completed in 1841, under the supervision of Andrew Scott Waugh. To his dismay, much of his time was spent on administrative concerns, as well as combating criticism from home. The East India Company had provisionally appointed Thomas Jervis as Everest's successor, and Jervis subsequently delivered a series of lectures to the Royal Society on the perceived deficiencies of Everest's methods. In response, Everest penned a series of open letters to Prince Augustus Frederick, Duke of Sussex
Prince Augustus Frederick, Duke of Sussex, (27 January 1773 – 21 April 1843) was the sixth son and ninth child of King George III and his queen consort, Charlotte of Mecklenburg-Strelitz. He was the only surviving son of George III who did not ...
, the society's president, in which he lambasted the society "for meddling in matters of which they know little". Jervis withdrew from consideration, and Everest successfully secured the appointment of his protégé Waugh as his successor. He resigned in November 1842 and his commission was formally revoked in December 1843, at which point he returned to England.[
]
Later life
In 1845 Everest was a passenger on the first voyage of the SS ''Great Britain'', which was the first crossing of any ocean on the world by a screw propelled steamship. In 1847, Everest published ''An Account of the Measurement of Two Sections of the Meridional Arc of India'', for which he was awarded a medal by the Royal Astronomical Society
(Whatever shines should be observed)
, predecessor =
, successor =
, formation =
, founder =
, extinction =
, merger =
, merged =
, type = NG ...
. He was later elected to fellowship of the Royal Asiatic Society
The Royal Asiatic Society of Great Britain and Ireland, commonly known as the Royal Asiatic Society (RAS), was established, according to its royal charter of 11 August 1824, to further "the investigation of subjects connected with and for the en ...
and the Royal Geographical Society
The Royal Geographical Society (with the Institute of British Geographers), often shortened to RGS, is a learned society and professional body for geography based in the United Kingdom. Founded in 1830 for the advancement of geographical scien ...
. Everest was promoted to colonel
Colonel (abbreviated as Col., Col or COL) is a senior military officer rank used in many countries. It is also used in some police forces and paramilitary organizations.
In the 17th, 18th and 19th centuries, a colonel was typically in charge ...
in 1854, made a Commander of the Order of the Bath
The Most Honourable Order of the Bath is a British order of chivalry founded by George I on 18 May 1725. The name derives from the elaborate medieval ceremony for appointing a knight, which involved bathing (as a symbol of purification) as ...
in February 1861, and created a Knight Bachelor
The title of Knight Bachelor is the basic rank granted to a man who has been knighted by the monarch but not inducted as a member of one of the organised orders of chivalry; it is a part of the British honours system. Knights Bachelor are ...
in March 1861. He died at his home in Hyde Park Gardens on 1 December 1866, and was buried in St Andrew's Church, Hove, near Brighton
Brighton () is a seaside resort and one of the two main areas of the City of Brighton and Hove in the county of East Sussex, England. It is located south of London.
Archaeological evidence of settlement in the area dates back to the Bronze A ...
.[
]
Naming of Mount Everest
George Everest had no direct connection with the mountain that bears his name, which he never saw. He was, however, responsible for hiring Andrew Scott Waugh, who made the first formal observations of the mountain, and Radhanath Sikdar
Radhanath Sikdar (Bengali: রাধানাথ শিকদার; 5 October 1813 – 17 May 1870) was an Indian mathematician who is best known for calculating the height of Mount Everest. He was the first person to calculate the height of M ...
, who calculated its height. Before its significance was realised, Mount Everest was originally known as Peak "B" and later as Peak XV. In March 1856, Waugh wrote to the Royal Geographical Society
The Royal Geographical Society (with the Institute of British Geographers), often shortened to RGS, is a learned society and professional body for geography based in the United Kingdom. Founded in 1830 for the advancement of geographical scien ...
to announce that the mountain was believed to be the highest in the world, and proposed that it be named "after my illustrious predecessor", as it was "without any local name that we can discover" – the "native appellation, if it has any, will not very likely be ascertained before we are allowed to penetrate into Nepal". There were in fact several native names among the Nepal
Nepal (; ne, नेपाल ), formerly the Federal Democratic Republic of Nepal ( ne,
सङ्घीय लोकतान्त्रिक गणतन्त्र नेपाल ), is a landlocked country in South Asia. It is ma ...
ese and Tibet
Tibet (; ''Böd''; ) is a region in East Asia, covering much of the Tibetan Plateau and spanning about . It is the traditional homeland of the Tibetan people. Also resident on the plateau are some other ethnic groups such as Monpa people, ...
ans, but those areas were closed off to the British at the time and people living further to the south of the Himalayas did not have a specific name for the peak. In the decade after 1856, Waugh's proposal was widely debated by the Royal Geographical Society and similar bodies. Other scholars of India put forward native names that they believed to be correct, such as Brian Houghton Hodgson
Brian Houghton Hodgson (1 February 1800 or more likely 1801 – 23 May 1894) was a pioneer naturalist and ethnologist working in India and Nepal where he was a British Resident. He described numerous species of birds and mammals from the Hima ...
's "Deva-dhunga" and Hermann Schlagintweit's "Gaurisankar". Everest himself objected to his name being used, as "the native of India" could not pronounce it and it could not be easily written in Hindi
Hindi (Devanāgarī: or , ), or more precisely Modern Standard Hindi (Devanagari: ), is an Indo-Aryan language spoken chiefly in the Hindi Belt region encompassing parts of northern, central, eastern, and western India. Hindi has been ...
. Nonetheless, in 1865 the society officially settled on "Mount Everest" as the name.
Family
Everest had several siblings, including two younger brothers. George's first younger brother was Robert Everest, chaplain to the East India Company and author of ''A Journey Through the United States and Part of Canada''. His second (his youngest brother) was the Thomas Roupell Everest, the father of Mary Everest and a lay homoeopath
Homeopathy or homoeopathy is a pseudoscientific system of alternative medicine. It was conceived in 1796 by the German physician Samuel Hahnemann. Its practitioners, called homeopaths, believe that a substance that causes symptoms of a dise ...
.
Everest's third child, Ethel Everest, was an associate of Emma Cons and friend of Lilian Baylis. She provided financial support for the founding of Morley College in south London.
One of Everest's sons, Lancelot Feilding Everest, was educated at Harrow School
Harrow School () is a Public school (United Kingdom), public school (English Independent school (United Kingdom), independent boarding school for boys) in Harrow on the Hill, Greater London, England. The school was founded in 1572 by John Lyon (sc ...
and Trinity College, Cambridge
Trinity College is a constituent college of the University of Cambridge. Founded in 1546 by King Henry VIII, Trinity is one of the largest Cambridge colleges, with the largest financial endowment of any college at either Cambridge or Oxford. ...
, and was called to the Bar by Lincoln's Inn
The Honourable Society of Lincoln's Inn is one of the four Inns of Court in London to which barristers of England and Wales belong and where they are called to the Bar. (The other three are Middle Temple, Inner Temple and Gray's Inn.) Lincol ...
. He practised as a barrister in chambers in London and was also the principal author of ''The Law of Estoppel''. Lancelot's eldest son, Cyril Feilding Everest, enlisted in the Canadian Infantry on 17 November 1914 and was killed in action on 9 October 1916 at the Battle of the Somme
The Battle of the Somme (French: Bataille de la Somme), also known as the Somme offensive, was a battle of the First World War fought by the armies of the British Empire and French Third Republic against the German Empire. It took place be ...
.
Everest's niece, Mary Everest, married mathematician George Boole
George Boole (; 2 November 1815 – 8 December 1864) was a largely self-taught English mathematician, philosopher, and logician, most of whose short career was spent as the first professor of mathematics at Queen's College, Cork in ...
in Gloucestershire on 11 September 1855. In spite of the absence of formal training, Mary was a fine mathematician in her own right, as was one of her daughters, Alicia Boole Stott. Alicia's son, Leonard Boole Stott, studied medicine and became a pioneer in the treatment and control of tuberculosis
Tuberculosis (TB) is an infectious disease usually caused by '' Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, ...
, work for which he was later appointed an OBE Mary Boole's daughter Margaret was the mother of Sir Geoffrey Ingram Taylor OM, a graduate of Trinity College, Cambridge, a renowned mathematician and physicist, and a major figure in fluid dynamics and wave theory.
Sir George Everest house in Mussoorie, India
Everest owned a house in Mussoorie
Mussoorie is a hill station and a municipal board, near Dehradun city in the Dehradun district of the Indian state of Uttarakhand. It is about from the state capital of Dehradun and north of the national capital of New Delhi. The hill s ...
, Uttarakhand, India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area, the List of countries and dependencies by population, second-most populous ...
, for about 11 years. He purchased it, sight unseen, from General Whish. Although now virtually derelict, it still has its roof, and there have been various plans to make it into a museum.
Built in 1832, the house is known today as Sir George Everest's House and Laboratory, or Park House. The house is situated in Park Estate about west of Gandhi Chowk / Library Bazaar (the west end of Mall Road in Mussoorie). Its location has panoramic views of the Doon Valley on one side and the Aglar River valley and the Himalayan Range to the north.
The house is under the jurisdiction of the Tourism Department. There are underground water cisterns (or perhaps pits for storing ice, since water is scarce in the area) that are quite deep and lie uncovered in the front yard outside the house, filled with litter and posing danger of slipping.
The interior has been stripped but the fireplaces, roof, and the door and window frames still remain. The house is secured by steel grills and cannot be entered. Now that this property is better known and the access road has been improved, the walls are covered with graffiti and then periodically whitewashed clean.
Recent new fencing, tree planting and the construction of a ticket booth (as of late 2015) indicate that at some point it will cost to enter the property. The inside has signs of renovation several years ago, such as ceramic floor tiles in the kitchen and electrical switch boxes. Conservation architects at the Indian National Trust are vying for this project.
References
Further reading
* John Keay. 2000. ''The Great Arc''. London: Harper Collins. .
* J. R. Smith. 1999. ''Everest: The Man and the Mountain''. Caithness: Whittles Publishing. .
*Dean, Riaz. 2019. ''Mapping The Great Game: Explorers, Spies & Maps in Nineteenth-century Asia''. Oxford: Casemate (UK). pp. 100–123 (Chap.4). ISBN
The International Standard Book Number (ISBN) is a numeric commercial book identifier that is intended to be unique. Publishers purchase ISBNs from an affiliate of the International ISBN Agency.
An ISBN is assigned to each separate edition a ...
978-1-61200-814-1.
External links
*
* https://www.explortheinfinity.com/george-everests-house/
George Everest Travel Guide, History
Photographs of Sir George Everest's house and laboratory, in Mussoorie, India
* https://www.theguardian.com/theguardian/from-the-archive-blog/2011/jul/21/mount-everest-name-1856
* http://www.nndb.com/people/583/000195995/
* https://www.historychannel.com.au/this-day-in-history/150th-anniversary-death-sir-george-everest/
* http://www.themodernantiquarian.com/site/530/gwernvale.html
* http://www.megalithic.co.uk/article.php?sid=4060
{{DEFAULTSORT:Everest, George
1790 births
1866 deaths
Burials in Sussex
Fellows of the Royal Geographical Society
Fellows of the Royal Society
Graduates of the Royal Military Academy, Woolwich
Mount Everest
People from Crickhowell
Royal Artillery officers
Surveyors General of India
British surveyors
British geographers
Knights Commander of the Order of the Bath
Knights Bachelor