Denis Albert Bardou (15 February 1841 – 14 March 1893) was a French manufacturer of precision optical instruments.

Early life

He was born in Paris, the son of Pierre Gabriel Bardou, optician, and Gertrude Aglaé Anna Guichard. Denis Albert's grandfather had founded the Maison Bardou in 1819, an optical company in Paris, which had then passed to his father.

Career

In 1865, Denis Albert assumed control of the family business.Légion d’honneur file, Denis Albert Bardou, cote LH/114/21.
/ref> The company was located at his residence at 55, rue de Chabrol. The company manufactured and sold astronomical

telescope A telescope is a device used to observe distant objects by their emission, Absorption (electromagnetic radiation), absorption, or Reflection (physics), reflection of electromagnetic radiation. Originally, it was an optical instrument using len ...

s, spyglasses,

binoculars Binoculars or field glasses are two refracting telescopes mounted side-by-side and aligned to point in the same direction, allowing the viewer to use both eyes (binocular vision) when viewing distant objects. Most binoculars are sized to be held ...

microscopes A microscope () is a laboratory instrument used to examine objects that are too small to be seen by the naked eye. Microscopy is the science of investigating small objects and structures using a microscope. Microscopic means being invisibl ...

and

opera glasses Opera glasses, also known as theater binoculars or Galilean binoculars, are compact, low-power optical magnification devices, usually used at performance events, whose name is derived from traditional use of binoculars at opera performances. Ma ...

. The telescopes included both equatorial and azimuthal models with silvered glass mirrors (10, 16, 20 cm). Between 1867 and 1891 the Bardou company won numerous awards at expositions of

Le Havre Le Havre is a major port city in the Seine-Maritime department in the Normandy (administrative region), Normandy region of northern France. It is situated on the right bank of the estuary of the Seine, river Seine on the English Channel, Channe ...

Philadelphia Philadelphia ( ), colloquially referred to as Philly, is the List of municipalities in Pennsylvania, most populous city in the U.S. state of Pennsylvania and the List of United States cities by population, sixth-most populous city in the Unit ...

, and Paris, including a gold medal at the Exposition Universelle in Paris in 1889. It furnished optical instruments to the French Ministère de la Guerre,

Ministère de la Marine The Ministry of the Navy () was a section of the French government – apart from the Ministry of War – that was in charge of the French navy and colonies. The ministry combined the administration of the navy, the colonies like New France an ...

and to foreign governments. The Maison Bardou and its fellow Paris-based competitors the Secrétan and Mailhat companies were among the leading French precision optics manufacturers of the early twentieth century. Bardou telescopes and optical products were widely exported to Europe, the United States and further afield.

Other activities

Bardou became a member of the

Société astronomique de France The Société astronomique de France (SAF; ), the France, French astronomical society, is a non-profit association in the public interest organized under French law (Association loi de 1901). Founded by astronomer Camille Flammarion in 1887, its ...

in 1888 (only one year after it was established). Advertisements for his company's telescopes appeared frequently in the pages of the society's bulletin.

Death and legacy

Bardou died on 14 March 1893 in his home in Paris. In 1896, Jules Vial, an engineer, became the successor to the Maison Bardou. He continued manufacturing telescopes under the name “Bardou” or “Bardou-Vial” for at least the next 15 years. By 1899, the company had moved to 59, rue Caulaincourt, Paris.

Notable telescopes

Besides manufacturing small telescopes, Bardou also built large ones upon request. * When Camille Flammarion built his observatory in Juvisy-sur-Orge in 1883, he commissioned Bardou to construct the large

equatorial mount An equatorial mount is a mount for instruments that compensates for Earth's rotation by having one rotational axis, called ''polar axis'', parallel to the Earth's axis of rotation. This type of mount is used for astronomical telescope mount, tel ...

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 ...

of 240 mm diameter and 3600 mm

focal length The focal length of an Optics, optical system is a measure of how strongly the system converges or diverges light; it is the Multiplicative inverse, inverse of the system's optical power. A positive focal length indicates that a system Converge ...

.Colette Aymard et Laurence-Anne Mayeur
« L’observatoire de Juvisy-sur-Orge, l’« univers d’un chercheur » à sauvegarder »
In Situ nline 29 , 2016, published 13 July 2016, consulted 16 June 2017. * In 1889, the Société Astronomique de France commissioned Bardou to build an equatorial mount refractor with a 108 mm diameter for the Observatory of the rue Serpente atop its new headquarters in the

6th arrondissement of Paris The 6th arrondissement of Paris (''VIe arrondissement'') is one of the 20 Arrondissements of Paris, arrondissements of the capital city of France. In spoken French, it is referred to as ''le sixième''. The arrondissement, called Luxembourg in ...

.Marie-Claude Paskoff. Observer à Paris avec la SAF hier et aujourd’hui. '' l’Astronomie'', vol. 119, décembre 2005, p. 641. Camille Flammarion at the eyepiece of his 9½-inch Bardou refractor at his Juvisy observatory.jpg,

Camille Flammarion Nicolas Camille Flammarion FRAS (; 26 February 1842 – 3 June 1925) was a French astronomer and author. He was a prolific author of more than fifty titles, including popular science works about astronomy, several notable early science fiction ...

at the eyepiece of his 9½-inch Bardou refractor at his Juvisy observatory Telescopio bardou.jpg, Bardou telescope that Camille Flammarion donated to the Sociedad Científica Camille Flammarion of

Jaén, Spain Jaén () is a Municipalities in Spain, municipality of Spain and the capital of the Jaén Province, Spain, province of Jaén, in the autonomous community of Andalusia. The city of Jaén is the administrative and industrial centre for the provinc ...

References

{{DEFAULTSORT:Bardou, Denis Albert Telescope manufacturers 1841 births 1893 deaths