Abbé Nicolas-Louis de Lacaille (; 15 March 171321 March 1762), formerly sometimes spelled de la Caille, was a

French French may refer to: * Something of, from, or related to France ** French language, which originated in France ** French people, a nation and ethnic group ** French cuisine, cooking traditions and practices Arts and media * The French (band), ...

astronomer An astronomer is a scientist in the field of astronomy who focuses on a specific question or field outside the scope of Earth. Astronomers observe astronomical objects, such as stars, planets, natural satellite, moons, comets and galaxy, galax ...

and geodesist who named 14 out of the 88 constellations. From 1750 to 1754, he studied the sky at the

Cape of Good Hope The Cape of Good Hope ( ) is a rocky headland on the Atlantic Ocean, Atlantic coast of the Cape Peninsula in South Africa. A List of common misconceptions#Geography, common misconception is that the Cape of Good Hope is the southern tip of Afri ...

in present-day

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

. Lacaille observed over 10,000 stars using a

refracting telescope A refracting telescope (also called a refractor) is a type of optical telescope that uses a lens (optics), lens as its objective (optics), objective to form an image (also referred to a dioptrics, dioptric telescope). The refracting telescope d ...

Biography

Born at Rumigny in the

Ardennes The Ardennes ( ; ; ; ; ), also known as the Ardennes Forest or Forest of Ardennes, is a region of extensive forests, rough terrain, rolling hills and ridges primarily in Belgium and Luxembourg, extending into Germany and France. Geological ...

in eastern France, he attended school in Mantes-sur-Seine (now

Mantes-la-Jolie Mantes-la-Jolie (, often informally called Mantes) is a Communes of France, commune in the Yvelines Departments of France, department in the Île-de-France Regions of France, region of north-central France. It is located to the west of Paris, f ...

). Afterwards, he studied rhetoric and philosophy at the Collège de Lisieux and then theology at the

Collège de Navarre The College of Navarre (, ) was one of the colleges of the historic University of Paris. It rivaled the University of Paris, Sorbonne and was renowned for its library. History The college was founded by Queen Joan I of Navarre in 1305, who provi ...

. He was left destitute in 1731 by the death of his father, who had held a post in the household of the duchess of Vendôme. However, he was supported in his studies by the Duc de Bourbon, his father's former patron. After he graduated, he did not accept ordination as a priest but took

deacon A deacon is a member of the diaconate, an office in Christian churches that is generally associated with service of some kind, but which varies among theological and denominational traditions. Major Christian denominations, such as the Cathol ...

's orders, becoming an

Abbé ''Abbé'' (from Latin , in turn from Greek , , from Aramaic ''abba'', a title of honour, literally meaning "the father, my father", emphatic state of ''abh'', "father") is the French word for an abbot. It is also the title used for lower-ranki ...

. He concentrated thereafter on science, and, through the patronage of

Jacques Cassini Jacques Cassini (18 February 1677 – 16 April 1756) was a French astronomer, son of the famous Italian astronomer Giovanni Domenico Cassini. He was known as Cassini II. Biography Cassini was born at the Paris Observatory. He was first admitted ...

, obtained employment, first in

surveying Surveying or land surveying is the technique, profession, art, and science of determining the land, terrestrial Plane (mathematics), two-dimensional or Three-dimensional space#In Euclidean geometry, three-dimensional positions of Point (geom ...

the coast from

Nantes Nantes (, ; ; or ; ) is a city in the Loire-Atlantique department of France on the Loire, from the Atlantic Ocean, Atlantic coast. The city is the List of communes in France with over 20,000 inhabitants, sixth largest in France, with a pop ...

Bayonne Bayonne () is a city in southwestern France near the France–Spain border, Spanish border. It is a communes of France, commune and one of two subprefectures in France, subprefectures in the Pyrénées-Atlantiques departments of France, departm ...

, then, in 1739, in remeasuring the

French meridian arc The Paris meridian is a meridian line running through the Paris Observatory in Paris, France – now longitude 2°20′14.02500″ East. It was a long-standing rival to the Greenwich meridian as the prime meridian of the world. The "Paris meridi ...

, for which he is honoured with a pyramid at

Juvisy-sur-Orge Juvisy-sur-Orge (, literally ''Juvisy on Orge'') is a commune in the Essonne department in Île-de-France in northern France. It is located southeast of Paris and a few kilometres south of Orly Airport. The city is known for Gare de Juvisy, ...

. The success of this difficult operation, which occupied two years, and achieved the correction of the anomalous result published by

in 1718, was mainly due to Lacaille's industry and skill. He was rewarded by admission to the Royal Academy of Sciences and appointment as Professor of mathematics in the Mazarin college of the

University of Paris The University of Paris (), known Metonymy, metonymically as the Sorbonne (), was the leading university in Paris, France, from 1150 to 1970, except for 1793–1806 during the French Revolution. Emerging around 1150 as a corporation associated wit ...

, where he constructed a small observatory fitted for his own use. He was the author of a number of influential textbooks and a firm advocate of Newtonian gravitational theory. His students included

Antoine Lavoisier Antoine-Laurent de Lavoisier ( ; ; 26 August 17438 May 1794), When reduced without charcoal, it gave off an air which supported respiration and combustion in an enhanced way. He concluded that this was just a pure form of common air and that i ...

and

Jean Sylvain Bailly Jean Sylvain Bailly (; 15 September 1736 – 12 November 1793) was a French astronomer, mathematician, freemason, and political leader of the early part of the French Revolution. He presided over the Tennis Court Oath, served as the mayor of ...

, both of whom were later guillotined during the French Revolution.

Voyage to the Cape of Good Hope

His desire to determine the distances of the planets trigonometrically, using the longest possible baseline, led him to propose, in 1750, an expedition to the

. This was officially sanctioned by

Roland-Michel Barrin de La Galissonière Roland-Michel Barrin de La Galissonière, Marquis de La Galissonière, sometimes spelled Galissonnière (; 10 November 1693 – 6 October 1756), was the French governor of New France from 1747 to 1749 and the victor in the Battle of Minorca ...

. There, he constructed an observatory on the shore of

Table Bay Table Bay (Afrikaans: ''Tafelbaai'') is a natural bay on the Atlantic Ocean overlooked by Cape Town and is at the northern end of the Cape Peninsula, which stretches south to the Cape of Good Hope. It was named because it is dominated by the fl ...

with the support of the Dutch Governor

Ryk Tulbagh Ryk Tulbagh (14 May 1699, Utrecht – 11 August 1771, Cape Town) was Governor of the Dutch Cape Colony from 27 February 1751 to 11 August 1771 under the Dutch East India Company (VOC). Tulbagh was the son of Dirk Tulbagh and Catharina Catte ...

. The primary result of his two-year stay was the observations of nearly 10,000 southern stars, the production of which required observing every night for over a year. In the course of his survey he took note of 42 nebulous objects. He also achieved his aim of determining the lunar and solar

parallax Parallax is a displacement or difference in the apparent position of an object viewed along two different sightline, lines of sight and is measured by the angle or half-angle of inclination between those two lines. Due to perspective (graphica ...

es (

Mars Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmosph ...

serving as an intermediary). This work required near-simultaneous observations from Europe which were carried out by

Jérôme Lalande Joseph Jérôme Lefrançois de Lalande (; 11 July 1732 – 4April 1807) was a French astronomer, freemason and writer. He is known for having estimated a precise value of the astronomical unit (the distance from the Earth to the Sun) using measu ...

. His southern catalogue, called ''Coelum Australe Stelliferum'', was published posthumously in 1763. He found it necessary to introduce 14 new

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The first constellati ...

s which have since become standard. One of these was Mons Mensae, the only constellation named after a terrestrial feature (the

Table Mountain Table Mountain (; ) is a flat-topped mountain forming a prominent landmark overlooking the city of Cape Town in South Africa. It is a significant tourist attraction, with many visitors using the Table Mountain Aerial Cableway, cableway or hik ...

). An 1890 study of this catalogue by B. A. Gould found a considerable number of errors. While at the

Cape A cape is a clothing accessory or a sleeveless outer garment of any length that hangs loosely and connects either at the neck or shoulders. They usually cover the back, shoulders, and arms. They come in a variety of styles and have been used th ...

, Lacaille performed an

arc measurement Arc measurement, sometimes called degree measurement (), is the astrogeodetic technique of determining the radius of Earth and, by Circumference#Circle, extension, Earth's circumference, its circumference. More specifically, it seeks to determine ...

to determine the

radius of the Earth Earth radius (denoted as ''R''🜨 or ''R''E) is the distance from the center of Earth to a point on or near its surface. Approximating the figure of Earth by an Earth spheroid (an oblate ellipsoid), the radius ranges from a maximum (equatoria ...

in the southern hemisphere. He set out a baseline in the

Swartland The Swartland is a region of Western Cape Province that begins some north of Cape Town and consists of the area between the towns of Malmesbury, South Africa, Malmesbury in the south, Darling, Western Cape, Darling in the west, Piketberg in the ...

plain north of present-day Darling. Using

triangulation In trigonometry and geometry, triangulation is the process of determining the location of a point by forming triangles to the point from known points. Applications In surveying Specifically in surveying, triangulation involves only angle m ...

he then measured a 137 km arc of meridian between

Cape Town Cape Town is the legislature, legislative capital city, capital of South Africa. It is the country's oldest city and the seat of the Parliament of South Africa. Cape Town is the country's List of municipalities in South Africa, second-largest ...

and present-day

Aurora An aurora ( aurorae or auroras), also commonly known as the northern lights (aurora borealis) or southern lights (aurora australis), is a natural light display in Earth's sky, predominantly observed in high-latitude regions (around the Arc ...

, determining the

astronomical latitude In geography, latitude is a geographic coordinate that specifies the north-south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from −90° at the south pole to 90° at the ...

s of the end points by means of astronomical-geodetic observations. There is a memorial to his work at a location near Aurora, pictured here. His result suggested that the Earth was lengthened (prolate) instead of flattened (oblate) towards the south pole.

George Everest Sir George Everest, (, ; 4 July 1790 – 1 December 1866) was a British surveyor and geographer who served as Surveyor General of India from 1830 to 1843. After a military education, Everest joined the East India Company and arrived in I ...

, of the Indian Survey, while recuperating from an illness at the Cape nearly seventy years later, suggested that Lacaille's latitude observations had been affected by the

deflection of the vertical The vertical deflection (VD) or deflection of the vertical (DoV), also known as deflection of the plumb line and astro-geodetic deflection, is a measure of how far the gravity direction at a given point of interest is rotated by local mass anoma ...

, caused by

gravitational attraction In physics, gravity (), also known as gravitation or a gravitational interaction, is a fundamental interaction, a mutual attraction between all massive particles. On Earth, gravity takes a slightly different meaning: the observed force be ...

of Table Mountain at the southern end and by the Piketberg Mountain at the northern. In 1838,

Thomas Maclear Thomas Maclear (17 March 1794 – 14 July 1879) was an Ireland, Irish-born Cape Colony astronomer who became Her Majesty's astronomer at the Cape of Good Hope. Early life Born on 17 March 1794, in Newtownstewart, the eldest son of Rev. James ...

, who was Astronomer Royal at the Cape, repeated the measurements over a longer baseline (

Maclear's arc measurement Thomas Maclear (17 March 1794 – 14 July 1879) was an Irish-born Cape Colony astronomer who became Her Majesty's astronomer at the Cape of Good Hope. Early life Born on 17 March 1794, in Newtownstewart, the eldest son of Rev. James Maclear ...

) and ultimately confirmed Everest's conjecture.

Maclear's Beacon Maclear's Beacon is a triangulation station used in Maclear's arc measurement for Earth's circumference determination. The beacon is situated on top of Table Mountain in Cape Town, South Africa. It is situated on the Eastern end on the plateau ...

was erected on the Table Mountain in

to help with the verification.

Computing

During his voyage to the southern hemisphere as a passenger on the vessel ''Le Glorieux'', captained by the noted hydrographer Jean-Baptiste d'Après de Mannevillette, Lacaille became conscious of the difficulties in determining positions at sea. On his return to Paris he prepared the first set of tables of the Moon's position that was accurate enough to use for determining time and longitude by the method of 'Lunars' ( Lunar distances) using the orbital theory of Clairaut. Lacaille worked hard at astronomical calculations; apart from constructing astronomical

ephemerides In astronomy and celestial navigation, an ephemeris (; ; , ) is a book with tables that gives the trajectory of naturally occurring astronomical objects and artificial satellites in the sky, i.e., the position (and possibly velocity) over time. ...

and mathematical tables, he calculated a table of

eclipse An eclipse is an astronomical event which occurs when an astronomical object or spacecraft is temporarily obscured, by passing into the shadow of another body or by having another body pass between it and the viewer. This alignment of three ...

s for 1800 years. Lalande said of him that, during a comparatively short life, he had made more observations and calculations than all the astronomers of his time put together.

Later life

On his return to Paris in 1754, following a diversion to

Mauritius Mauritius, officially the Republic of Mauritius, is an island country in the Indian Ocean, about off the southeastern coast of East Africa, east of Madagascar. It includes the main island (also called Mauritius), as well as Rodrigues, Ag ...

, Lacaille was distressed to find himself an object of public attention. He resumed his work at the Mazarin College. In 1757 he published his ''Astronomiae Fundamenta Novissimus'', containing a list of about 400 bright stars with positions corrected for aberration and

nutation Nutation () is a rocking, swaying, or nodding motion in the axis of rotation of a largely axially symmetric object, such as a gyroscope, planet, or bullet in flight, or as an intended behaviour of a mechanism. In an appropriate reference fra ...

. He carried out calculations on comet orbits and was responsible for giving

Halley's Comet Halley's Comet is the only known List of periodic comets, short-period comet that is consistently visible to the naked eye from Earth, appearing every 72–80 years, though with the majority of recorded apparitions (25 of 30) occurring after ...

its name. His last public lecture, given on 14 September 1761 at the Royal Academy of Sciences, summarised the improvements to astronomy that had occurred during his lifetime. His death, probably caused in part by over-work, occurred in 1762. He was buried in the vaults of the Mazarin College, now the

Institut de France The ; ) is a French learned society, grouping five , including the . It was established in 1795 at the direction of the National Convention. Located on the Quai de Conti in the 6th arrondissement of Paris, the institute manages approximately ...

in Paris.

Honours

In 1754, he was elected a foreign member of the

Royal Swedish Academy of Sciences The Royal Swedish Academy of Sciences () is one of the Swedish Royal Academies, royal academies of Sweden. Founded on 2 June 1739, it is an independent, non-governmental scientific organization that takes special responsibility for promoting nat ...

. He was also an honorary member of the academies of Saint Petersburg and Berlin, the

Royal Society The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, re ...

of London and the

Royal Society of Göttingen Royal may refer to: People * Royal (name), a list of people with either the surname or given name * A member of a royal family or royalty Places United States * Royal, Arkansas, an unincorporated community * Royal, Illinois, a village * Royal, ...

, and the Institute of Bologna. Lacaille has the honor of naming 14 different constellations: *

Antlia Antlia (; from Ancient Greek ''ἀντλία'') is a constellation in the Southern Celestial Hemisphere. Its name means "pump" in Latin and Greek language, Greek; it represents an air pump. Originally Antlia Pneumatica, the constellation was es ...

Caelum Caelum is a faint constellation in the southern sky, introduced in the 1750s by Nicolas Louis de Lacaille and counted among the 88 modern constellations. Its name means "chisel" in Latin, and it was formerly known as Caelum Sculptorium ("Engrave ...

Circinus Circinus is a small, faint constellation in the southern sky, first defined in 1756 by the French astronomer Nicolas-Louis de Lacaille. Its name is Latin for compass, referring to the drafting tool used for drawing circles (it should not be con ...

Fornax Fornax () is a constellation in the southern celestial hemisphere, partly ringed by the celestial river Eridanus (constellation), Eridanus. Its name is Latin for furnace. It was named by French astronomer Nicolas Louis de Lacaille in 1756. Forna ...

* Horologium * Mensa *

Microscopium Microscopium ("the Microscope") is a minor constellation in the southern celestial hemisphere, one of twelve created in the 18th century by French astronomer Nicolas-Louis de Lacaille and one of several depicting scientific instruments. The name ...

Norma Norma may refer to: * Norma (given name), a given name (including a list of people with the name) ** Norma Lizbeth Ramos, a Mexican bullying victim Astronomy *Norma (constellation) * 555 Norma, a minor asteroid * Cygnus Arm or Norma Arm, a spiral ...

Octans Octans is a faint constellation located in the deep southern celestial hemisphere, Southern Sky. Its name is Latin for the eighth part of a circle, but it is named after the octant (instrument), octant, a navigational instrument. Devised by kingd ...

Pictor Pictor is a constellation in the Southern Celestial Hemisphere, located between the star Canopus and the Large Magellanic Cloud. Its name is Latin for painter, and is an abbreviation of the older name Equuleus Pictoris (the "painter's easel"). ...

Pyxis Pyxis is a small and faint constellation in the southern sky. Abbreviated from Pyxis Nautica, its name is Latin for a mariner's compass (contrasting with Circinus, which represents a draftsman's compasses). Pyxis was introduced by Nicolas-Louis ...

Reticulum Reticulum is a small, faint constellation in the southern sky. Its name is Latin for a small net, or reticle—a net of crosshairs at the focus of a telescope eyepiece that is used to measure star positions. The constellation is best viewed b ...

Sculptor Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable sc ...

Telescopium Telescopium is a minor constellation in the southern Celestial sphere, celestial hemisphere, one of twelve named in the 18th century by French astronomer Nicolas-Louis de Lacaille and one of several depicting scientific instruments. Its name i ...

The crater " La Caille" on the

Moon The Moon is Earth's only natural satellite. It Orbit of the Moon, orbits around Earth at Lunar distance, an average distance of (; about 30 times Earth diameter, Earth's diameter). The Moon rotation, rotates, with a rotation period (lunar ...

is named after him.

Asteroid An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). As ...

9135 Lacaille (AKA 7609 P-L and 1994 EK6), discovered on 17 October 1960 by

Cornelis Johannes van Houten Cornelis Johannes "Kees" van Houten (18 February 1920 – 24 August 2002) was a Dutch people, Dutch astronomer. Early life and education Born in The Hague, he spent his entire career at Leiden University except for a brief period (1954–1956) as ...

Ingrid van Houten-Groeneveld Ingrid van Houten-Groeneveld (; ; 21 October 1921 – 30 March 2015) was a Dutch astronomer. Background In a jointly credited trio with Tom Gehrels and her husband Cornelis Johannes van Houten, she was the discoverer of many thousands of as ...

and

Tom Gehrels Anton M.J. "Tom" Gehrels (February 21, 1925 – July 11, 2011) was a Dutch–American astronomer, Professor of Planetary Sciences, and Astronomer at the University of Arizona, Tucson. Biography Youth and education Gehrels was born at Ha ...

Palomar Observatory The Palomar Observatory is an astronomical research observatory in the Palomar Mountains of San Diego County, California, United States. It is owned and operated by the California Institute of Technology (Caltech). Research time at the observat ...

, was also named after him. In honor of his contribution to the study of the southern hemisphere sky, a 60-cm telescope at

Réunion Island Réunion (; ; ; known as before 1848) is an island in the Indian Ocean that is an overseas department and region of France. Part of the Mascarene Islands, it is located approximately east of the island of Madagascar and southwest of the is ...

will be named the Lacaille Telescope.(French)

Main works

*''Leçons élémentaires de Mathématiques'' (1741), frequently reprinted *ditto ''de Mécanique'' (1743), &c. *ditto ''d'Astronomie'' (1746); 4th edition augmented by Lalande (1779) * 2nd edition *Calculations by him of eclipses for eighteen hundred years were inserted in ''L'Art de vérifier les dates'' by

Benedictine The Benedictines, officially the Order of Saint Benedict (, abbreviated as O.S.B. or OSB), are a mainly contemplative monastic order of the Catholic Church for men and for women who follow the Rule of Saint Benedict. Initiated in 529, th ...

historian

Charles Clémencet Charles Clémencet (17035 August 1778) was a French Benedictine historian. He was born in Painblanc, in present-day Côte-d'Or, and was one of the authors who helped complete the great chronological work (the usual short form of a long title). H ...

(1750) *He communicated to the Academy in 1755 a classed catalogue of forty two southern nebulae, and gave in t. ii. of his ''Ephémérides'' (1755) practical rules for the employment of the lunar method of longitudes, proposing in his additions to

Pierre Bouguer Pierre Bouguer () (16 February 1698, Le Croisic – 15 August 1758, Paris) was a French mathematician, geophysicist, geodesist, and astronomer. He is also known as "the father of naval architecture". Career Bouguer's father, Jean Bouguer, ...

's ''Traité de Navigation'' (1760) the model of a nautical almanac. *''Tabulae Solares'' (1758)

Star catalogues

*"Remarques sur le Catalogue suivant des principales Étoiles du Ciel",
Éphémérides des mouvemens célestes
pour dix années, depuis 1755 jusqu'en 1765, et pour le meridien de la ville de Paris'' (1755), pp. xlix-lxiii. *"Table des Ascensions Droites et des Declinaisons Apparentes des Etoiles australes renfermées dans le tropique du Capricorne..."
''Memoires Academie Royale des Sciences'' pour 1752
(1756), pp. 539–592. (describing fourteen new constellations) *"Stellarum ascensiones rectae verae & declinationes verae ad Epocham anni ineuntis 1750",
Astronomiae fundamenta
novissimis solis et stellarum observationibus stabilita, Lutetiae in Collegio mazarineo et in Africa ad Caput Bonae-Spei'' (1757), pp. 233–237. (containing a standard catalogue of 398 stars) *"Stellarum longitudines & latitudines verae ad annum ineuntum 1750, Earum praecipue quae Zodiacales sunt", ''Astronomiae fundamenta'' (1757), pp. 238–239. *"Stellarum Australium Catalogus
''Coelum australe stelliferum''
''seu, Observationes ad Construendum Stellarum Australium Catalogum Institutae: in Africa ad Caput Bonae-Spei'' (1763), (edited by J. D. Maraldi), pp. 139–158. *"Catalogue suivant des principales Étoiles du Ciel, pour le commencement de l'Anee 1750",
Éphémérides des mouvemens célestes
pour dix annees, depuis 1765 jusqu'en 1775, et pour le meridien de la ville de Paris'' (1763), pp. lvii-lxiv. *"Observations sur 515 étoiles du Zodiaque", ''Éphémérides des mouvemens célestes, pour dix annees, depuis 1765 jusqu'en 1775'', (1763) pp. lxv-lxxvii.
''A catalogue of 9766 stars in the southern hemisphere,''
'for the beginning of the year 1750: from the observations of the Abbé de Lacaille, made at the cap of Good Hope in the years 1751 and 1752; with a preface by Sir J. F. W. Herschel'' (1847), giving zone observations of about 10,000 stars, re-edited by F. Baily

Star maps

* "Planisphere contenant les Constellations Celestes comprises entre le Pole Austral et le Tropique du Capricorne", ''Mem. de l'Ac. R. des Sc.'' 1752 (1756), p. 590, plate 20. (French) *
Coelum Australe
, ''Coelum australe stelliferum'' (1763). (Latin) * "Planisphere des Etoiles les Australes dressé par M. i'Abbé de la Caille", ''Atlas Celeste de Flamsteed'' (1776), 2nd ed., plate 29. (French)* "Planisphere des Etoiles les Australes dressé par M. i'Abbé de la Caille", ''Recueil de Planches de l'Encyclopédie par ordre de matieres'' (1789), vol. 7, plate 3. (French) * "Planisphere des Etoiles les Australes dressé par M. i'Abbé de la Caille", ''Atlas Celeste de Flamsteed'' (1795), 3rd ed., plate 29. (French)

Notes

References

*Jean-Baptiste Joseph Delambre, Histoire de l'astronomie au Dix-Huitième siècle, Paris, Bachelier, 1827. * David S. Evans: ''Lacaille: astronomer, traveller; with a new translation of his journal''. Tucson: Pachart, 1992 * I.S. Glass: ''Nicolas-Louis de La Caille, Astronomer and Geodesist''. Oxford: Oxford University Press, 2013 *N.L. de La Caille: ''Travels at the Cape, 1751–53: an annotated translation of Journal historique du voyage fait au Cap de Bonne-Espérance ...''; transl. and ed. by R. Raven-Hart. Cape Town: A.A. Balkema for the Friends of the South African Library, 1976 *Journal historique du voyage fait au Cap de Bonne-Espérance par feu M. l'abbé de La Caille..., Paris, Guillyn, 1763. This work was edited by Abbé Carlier, who attached a discourse on La Caille's life. *
Virtual exhibition on Paris Observatory digital library
{{DEFAULTSORT:Lacaille, Nicolas Louis De 1713 births 1762 deaths People from Ardennes (department) Academic staff of the University of Paris 18th-century French astronomers Members of the French Academy of Sciences Members of the Royal Swedish Academy of Sciences Fellows of the Royal Society Honorary members of the Saint Petersburg Academy of Sciences Catholic clergy scientists French geodesists