{"arkId":"cl010112711","url":"https:\/\/collections.louvre.fr\/ark:\/53355\/cl010112711","modified ":"2025-12-10","title":"T\u00e9lescope \u00e0 r\u00e9flexion","titleComplement":"","denominationTitle":[{"type":"Titre","value":"T\u00e9lescope \u00e0 r\u00e9flexion"}],"displayDateCreated":"Epoque \/ p\u00e9riode : Louis XV (1715-1774) (Occident-\u003E\u00e9poque moderne = Ancien R\u00e9gime-\u003Edynastie des Bourbons)\r\n\r\nDate de cr\u00e9ation\/fabrication : vers 1760","currentLocation":"Sully, [OArt] Salle 609 - Nicolas et Simone Landau, Vitrine 4","room":"Salle 609, Aile Aile Sully, Niveau 1","isMuseesNationauxRecuperation":false,"dateCreated":[{"startYear":1760,"endYear":"","imprecision":"vers","text":"3e quart du XVIIIe si\u00e8cle","type":"Date de cr\u00e9ation\/fabrication","doubt":""}],"creator":[{"label":"Passemant, Claude-Sim\u00e9on","attributionLevel":"Attribution actuelle","linkType":"","dates":[{"date":"1702","place":"","type":"date de naissance"},{"date":"1769","place":"","type":"date de mort"}],"creatorRole":"Fabricant, facteur","authenticationType":"marque (estampilles, poin\u00e7ons...)","doubt":"","attributedBy":"","attributedYear":"","wikidata":"Q26870227"}],"objectNumber":[{"value":"OA 10766","type":"Num\u00e9ro principal"}],"collection":"D\u00e9partement des Objets d\u0027art du Moyen Age, de la Renaissance et des temps modernes","printsDrawingsEntity":"","printsDrawingsCollection":"","objectType":"instrument scientifique (mesure, calcul, observation, etc.)","originalObject":"","printState":"","description":"\u0022Le t\u00e9lescope, port\u00e9 sur un pied tourn\u00e9, est mont\u00e9 sur un genou auquel il est reli\u00e9 par une plaque viss\u00e9e sur son ventre. Le dispositif optique est constitu\u00e9 d\u2019un grand miroir circulaire du c\u00f4t\u00e9 de l\u2019oculaire avec une ouverture en son centre ; il collecte la lumi\u00e8re et la renvoie sur un petit miroir \u00e0 l\u2019oppos\u00e9 qui dirige de nouveau les rayons vers les lentilles de l\u2019oculaire.  La mise au point se fait en tournant l\u2019extr\u00e9mit\u00e9 du tube principal ; des rails en spirale font coulisser une petite pi\u00e8ce reli\u00e9e au petit miroir pour le faire avancer ou reculer. Cette extr\u00e9mit\u00e9 est aussi prot\u00e9g\u00e9e d\u2019un couvercle, tandis que l\u2019oculaire poss\u00e8de une targette.\r\nEn 1668, Isaac Newton avait r\u00e9alis\u00e9 le premier t\u00e9lescope \u00e0 r\u00e9flexion capable de fonctionner. Ce type de t\u00e9lescope avait l\u2019avantage de donner, avec une petite taille, un grossissement identique aux immenses lunettes de l\u2019\u00e9poque ; il permettait aussi d\u2019\u00e9viter le probl\u00e8me de l\u2019aberration chromatique (les rayons de diff\u00e9rentes couleurs composant la lumi\u00e8re blanche ne se focalisent pas tous au m\u00eame point lorsqu\u2019ils passent \u00e0 travers une lentille de verre). La difficult\u00e9 de fabrication de ces instruments retarda, n\u00e9anmoins, leur production jusqu\u2019aux ann\u00e9es 1720. En France, Claude-Sim\u00e9on Passemant fut le premier \u00e0 les commercialiser et, en 1738, il contribua \u00e0 leur diffusion en publiant un trait\u00e9 sur le sujet ; on y trouve notamment la composition de ses miroirs : \u00e0 20 onces de cuivre rouge, il m\u00eale 9 onces d\u2019\u00e9tain et 8 onces d\u2019arsenic (Passemant, 1738).\u0022 (Fr\u00e9montier-Murphy, 2002)","inscriptions":"Signature : \r ; \u0022PASSEMANT AU LOUVRE. AU DESSUS. DE LACADEMIE. FRANCOISE. A PARIS\u0022 (\u00e0 une extr\u00e9mit\u00e9 du tube principal)","namesAndTitles":"","onomastics":"","dimension":[{"type":"Hauteur","value":"43","displayDimension":"43 cm","unit":"cm","anteriorPrecision":"","posteriorPrecision":"","tri":1,"note":""},{"type":"Longueur","value":"23,7","displayDimension":"23,7 cm","unit":"cm","anteriorPrecision":"","posteriorPrecision":"","tri":2,"note":""},{"type":"Longueur","value":"5,2","displayDimension":"5,2 cm","unit":"cm","anteriorPrecision":"","posteriorPrecision":"","tri":3,"note":""},{"type":"Diam\u00e8tre","value":"15,8","displayDimension":"15,8 cm","unit":"cm","anteriorPrecision":"","posteriorPrecision":"","tri":4,"note":""},{"type":"Diam\u00e8tre","value":"4,5","displayDimension":"4,5 cm","unit":"cm","anteriorPrecision":"","posteriorPrecision":"","tri":5,"note":""},{"type":"Diam\u00e8tre","value":"2","displayDimension":"2 cm","unit":"cm","anteriorPrecision":"","posteriorPrecision":"","tri":6,"note":""}],"shape":"","materialsAndTechniques":"Mat\u00e9riau\/Technique : Poirier teint\u00e9 noir lest\u00e9 de plomb, alliage cuivreux, galuchat de raie teint\u00e9 rose, miroir, verre\r\nMat\u00e9riau : poirier\r\nTechnique : teint\u00e9 = teint\u00e9e (techniques bambou\/ bois\/ corne\/ ivoire\/ \u00e9caille) (noir)\r\nMat\u00e9riau : plomb\r\nMat\u00e9riau : alliage cuivreux\r\nMat\u00e9riau : peau de raie\r\nTechnique : teint\u00e9 (techniques peaux\/cuir) (rose)\r\nMat\u00e9riau : miroir\r\nMat\u00e9riau : verre","placeOfCreation":"Palais du Louvre (Paris-\u003EPalais  = Palais du = Palais de = Palais de la = Palais des)","dateOfDiscovery":"","placeOfDiscovery":"","provenance":"","historicalContext":[],"objectHistory":"Collection Nicolas Landau (1887-1979) ; legs Marcelle Landau, 1980","jabachInventory":"","napoleonInventory":"","previousOwner":[{"value":"M. Landau, Nicolas","note":"","role":", Collectionneur"},{"value":"Mme Landau, Marcelle","note":" (don d\u0027un ensemble de 166 instruments scientifiques, en ex\u00e9cution des volont\u00e9s de son \u00e9poux Nicolas Landau)","role":", Donateur"}],"acquisitionDetails":[{"mode":"don manuel","doubt":"","dates":[{"type":"date","value":"1979","startYear":1979,"endYear":1979},{"type":"date de l\u0027arr\u00eat\u00e9\/d\u00e9cision","value":"22\/11\/1979","startYear":1979,"endYear":1979}]}],"ownedBy":"Etat","heldBy":"Mus\u00e9e du Louvre, D\u00e9partement des Objets d\u0027art du Moyen Age, de la Renaissance et des temps modernes","longTermLoanTo":"","index":{"Mode d\u0027acquisition":[{"value":"don manuel"}],"Period":[{"value":"Louis XV (1715-1774)"}],"Places":[{"value":"Palais du Louvre"}],"objectType":[{"value":"instrument scientifique (mesure, calcul, observation, etc.)"}]},"bibliography":[{"bibliographyRef":"Fabre, Alexia ; Malgouyres, Philippe (dir.), La lune : du voyage r\u00e9el aux voyages imaginaires, cat. exp. (Paris, Galeries nationales du Grand Palais, 1er avril-22 juillet 2019), Paris, R\u00e9union des mus\u00e9es nationaux-Grand Palais, 2019","bibliographyDate":"2019","bibliographyDetail":"p. 68, ill. 70, n\u00b0 61","comparison":false},{"bibliographyRef":"Fr\u00e9montier-Murphy, Camille, Les Instruments de math\u00e9mathiques, XVIe-XVIIIe si\u00e8cle : cadrans solaires, astrolabes, globes, n\u00e9cessaires de math\u00e9matiques, instruments d\u0027arpentage, microscopes, Paris, R\u00e9union des mus\u00e9es nationaux (RMN), 2002","bibliographyDate":"2002","bibliographyDetail":"p. 328-329, N\u00b0 207","comparison":false}],"exhibition":[{"value":"La lune. Du voyage r\u00e9el aux voyages imaginaires, Paris (Externe, France), Galeries nationales du Grand Palais, 01\/04\/2019 - 22\/07\/2019 "}],"relatedWork":[],"image":[{"urlImage":"https:\/\/collections.louvre.fr\/media\/cache\/large\/0000000021\/0000112711\/0000246777_OG.JPG","urlThumbnail":"https:\/\/collections.louvre.fr\/media\/cache\/small\/0000000021\/0000112711\/0000246777_OG.JPG","copyright":"\u00a9 2012 GrandPalaisRmn (mus\u00e9e du Louvre) \/ Martine Beck-Coppola","type":"","position":0},{"urlImage":"https:\/\/collections.louvre.fr\/media\/cache\/large\/0000000021\/0000112711\/0000246778_OG.JPG","urlThumbnail":"https:\/\/collections.louvre.fr\/media\/cache\/small\/0000000021\/0000112711\/0000246778_OG.JPG","copyright":"\u00a9 2012 GrandPalaisRmn (mus\u00e9e du Louvre) \/ Martine Beck-Coppola","type":"","position":1},{"urlImage":"https:\/\/collections.louvre.fr\/media\/cache\/large\/0000000021\/0000112711\/0000246779_OG.JPG","urlThumbnail":"https:\/\/collections.louvre.fr\/media\/cache\/small\/0000000021\/0000112711\/0000246779_OG.JPG","copyright":"\u00a9 2012 GrandPalaisRmn (mus\u00e9e du Louvre) \/ Martine Beck-Coppola","type":"","position":2}]}