Watch 1505
This article's factual accuracy is disputed. (April 2020) |
Manufacturer | Peter Henlein |
---|---|
Display | Analogue |
Introduced | 1505 |
Movement | Analogue |
The Watch 1505 /ˌwɒtʃ fɪfˈtiːn ˈəʊ ˈfɑːɪv/ (also named PHN1505 or Pomander Watch of 1505) is the world's first watch. It was crafted by the German inventor, locksmith and watchmaker Peter Henlein from Nuremberg, during the year 1505, in the early German Renaissance period, as part of the Northern Renaissance.[1][2][3] However, other German clockmakers were creating miniature timepieces during this period, and there is no definite evidence Henlein was the first.[4][5] It is the oldest watch in the world that still works. The watch is a small fire-gilded copper sphere, an oriental pomander, and combines German engineering with Oriental influences.[6] In 1987, the watch reappeared at an antiques and flea market in London.[1] The initial price estimation for this watch is between 50 and 80 million dollars (May 2014).[7]
History
[edit]Nuremberg
[edit]The years between 1470 and 1530 are generally considered as the heyday (Blütezeit) of the city of Nuremberg.[8] In that time, the city became a center of craft, science and humanism. The new worldview of the Renaissance took hold in the Bavarian city.[9] During the Middle-Ages, Nuremberg grew under the Hohenstaufen and Luxembourgers to become one of the most important cities in the Holy Roman Empire. One main reason for this was that Nuremberg was one of the two trading centers on the route between Italy and northern Europe. Thanks to this advantage, as well as burgeoning craftsmanship and long-distance trade, the city became wealthy. Based on this wealth, political, religious, artistic, cultural and technological aspects developed that would make Nuremberg one of the most important cultural centers of the Renaissance north of the Alps, and a center of humanism and Reformation.[9]
A popular quote about the Nuremberg Esprit (spirit of Inventions = Nürnberger Witz) from this time is: Nuremberg jokes and frills are known throughout the world.[10][a] Another well-known saying at the time of the Holy Roman Empire positioned the various different European centers of the age, including Nuremberg’s special atmosphere: “If I had Venice’s power, Augsburg’s splendor, Nuremberg’s esprit, Strasburg’s weapons and Ulm’s money, I would be the richest man in the world.”[11][b][12]
Watch Invention
[edit]The first timepieces to be worn, made in the 16th century initially in the German cities of Nuremberg and Augsburg, were transitional in size between clocks and watches.[13] Portable timepieces were made possible by the invention of the mainspring.[14][4] Peter Henlein was the first German craftsman to make ornamental timepieces worn as pendants, which were the first timepieces to be worn on the body. His fame (as the inventor of the watch) is based on a passage by Johann Cochläus in 1511.[c][5][15] Since then, Henlein is generally known as the inventor of the first portable watches.[16][17][18] In the early 16th century, he became the first to install small movements in the capsule of a pomander with olfactory essences.[19] In 1505, Peter Henlein of Nuremberg was the first to build the portable pomander watch, the first watch of the world.[d][21][22][23][24][25][26][27]
The production of this watch was made possible primarily by a previously unseen scale of miniaturization of the torsion pendulum and coil spring mechanism, placed in a technical unit by Peter Henlein, a technological innovation and novelty of the time, operating in all positions.[20][28][14]
Henlein created the pomander watch while he lived in the Franciscan Monastery in Nuremberg,[29][30] where he gained knowledge of the Oriental world gathered over centuries,[31] Henlein acquired the new techniques and tools which helped him creating the first watch in the form of a gilt pomander.[e][32]
In his lifetime, Henlein created other or similar types of watches (e.g., drum watches - the later called the Nuremberg eggs).[33][34] He also crafted a tower clock for Lichtenau castle in 1541, and was known as a maker of sophisticated scientific instruments.[5]
Rediscovery
[edit]The story of the watch's reappearance began in 1987, at an antique-flea market in London. The watch sequentially changed ownership between collectors who were unaware of its actual worth, until in 2002 a private collector purchased the pomander watch.[3] A committee assessed the watch in 2014, particularly the assertion that the pomander dates back to 1505, and was signed by Henlein himself.[35][32]
Aesthetics
[edit]The design consisted of two small half-spheres, joined by a binding hinge. The upper half of the pomander can be opened to reveal a second – slightly smaller – half-sphere underneath. The top of that inner sphere shows the dial. The upper surface of the dial shows Roman numbers for the first half of the day, and on the outer side of the dial Arabic numerals for the second half of the day. This shows the transition to the new use of numerals at this time in history.[19]
The pomander watch displays small engravings of the city of Nuremberg at the beginning of the 16th century, e. g. the Henkerturm built in the year 1320, which can still be visited today or the still standing Weinstadel. Other symbols are also engraved on the watch, such as sun, serpents or laurels engraved on the watch.[36]
Technical description
[edit]The casing consists of copper, fire gilded on the outside and fire silver-plated on the inside of the watch. Apart from a renewed brass sprocket, the movement is made completely of iron. The detailed dimensions are:[36][32]
- Casing diameter: 4.15 cm x 4.25 cm (with equator ring 4.5 cm) - Weight 38.5 g
- Movement diameter: 3.60 cm x 3.55 cm - Weight: 54.1 g
A key is used to wind up the watch movement. The Watch 1505 produces a calculated running time of 12 hours.[32]
Inscriptions
[edit]On the watch housing, an old Latin banner is engraved. The inscription is: DVT ME FUGIENT AGNOSCAM R. The possible two translations are:[32]
- 1505 - The time will escape me (Henlein), but I (the watch) will recognize the correct time
- In the year 1505 – My watches will flee (run), and recognize the correct time.
The letters „MDV PHN“ are engraved under the examined silver plating and were found on the inside of the casing underneath the outer face of the clock. The hypothetical indication of the engraving is: 1505 Peter Henlein Nuremberg.[32] Tiny PH-letters, often smaller than half a millimeter, were also found. Peter Henlein was a locksmith and had no qualification as a watchmaker, as there were none (there was no existing occupation or guild). He was not allowed to sign his work officially, as he was not a member of the locksmith's guild. In the early days of watchmaking, locksmiths often were involved in the production as they were accustomed to making small metal components.[32]
Symbolism of the watch
[edit]The Pomander (derived from the French pomme ‘ambre in German Bisamapfel) also called Riechapfel, was a status symbol from the Orient, and often represented first encounter by the Europeans with the fragrances of the Orient. It became as a valued symbolic gift of diplomatic exchange between leading personalities in from the East to the West, and was believed to have a healing and protective effect.[6][37] For example Jacob Cornelisz. van Oostsanen created 1518 a portrait of Jan Gerritz van Egmond van de Dijenborgh, the elected major of Alkmaar, in 1518, with a pomander in his hand.[38] The pomander form was spread in the Middle Ages from the Orient throughout Europe. The watch itself can be seen as a cultural encounter between the European engineering and the Oriental form.[6] Pomanders were worn due to the poor hygienic conditions in the cities. The musk-perfume inside the pomander had a disinfectant and odor resistant effect.[39]
The serpent is one of the oldest mythological symbols in civilization, going back as far as the Summer in Mesopotamia. The serpent eating its own tail (the Ouroboros) is a symbol for the infinity of the universe and the eternal life. It also represents the orbit of the sun,[40][41] duality,[42] and an Ancient Egyptian alchemist symbol (The All is one).[43][44]
The symbolism of the laurel passed over into Roman culture, which held laurels as a symbol of victory.[45] It is also associated with immortality,[46] with ritual purification, prosperity and health.[47][48]
The symbolism of the sun on the pomander, as the source of energy and light for life on earth has been a central object in culture and religion since prehistory. Ritual solar worship has given rise to solar deities in theistic traditions throughout the world, and solar symbolism is ubiquitous. Apart from its immediate connection to light and warmth, the sun is also important in timekeeping as the main indicator of the day and the year.[49]
Financial worth
[edit]A paper from 1524 records that Heinlein was paid 15 florins (one florin is approximately between 140 and 1000 modern US dollars)[50] for a gilt pomander watch.[51] The initial price estimation is around 50 - 80 million dollars, according to the AntiqueWeek magazine (May 2014).[7]
Examinations and confirmation
[edit]Several examinations (micro- and macro-photographic and metallurgical examinations, as well as a 3D computer tomography[52]) were made to proof the authenticity of the watch. The general examinations-result showed that the pomander watch was created by Henlein in the year 1505.[1][3][53][32]
There is also a confirmation of the date of invention, verifying that the engravings lie beneath under the layer of a medieval method of fire gilding. The invention was celebrated at the 400th anniversary of the German Watchmakers’ Association in 1905.[54][32] On this occasion, a monument fountain dedicated to Peter Henlein was built in Nuremberg.[55][56]
Also Johann Neudörfers also wrote in 1547 that Henlein invented the pomander watches (die bisam Köpf zu machen erfunden).[f][57]
The Walhalla in Donaustauf, which is a memorial for "politicians, sovereigns, scientists and artists of the German tongue",[58] honors Peter Henlein with the words inventor of the watch.[g][59]
Other pomander watches by Peter Henlein
[edit]Nowadays, there are only two preserved pomander watches in the world. The one from 1505 is in private ownership, and the Pomander Watch of Melanchthon, from 1530, which is owned by the Walters Art Museum in Baltimore. It was most probably a gift by the City of Nuremberg, to the Nuremberg Reformer Philipp Melanchthon and Peter Henlein was commissioned to create this personalized watch. Also an empty housing of a pomander watch can be found at the Wuppertal Watch Museum.[60][32]
The former watchmaker and art collector Jürgen Abeler from the Wuppertaler Watch Museum concludes about pomander watches in his book: „So if any one of the preserved watches at all should be linked with the person of Peter Henlein, it can only be this watch in the pomander.“[61]
Historical influences of the watch
[edit]This section may require cleanup to meet Wikipedia's quality standards. The specific problem is: grammar needs to be fixed, and the whole things needs to be rewritten to show how it's related to watch 1505 specifically. (May 2024) |
The systemized knowledge of the earliest-known civilization of the Sumer, such as systemized knowledge of astronomical calculations and mathematics (sexagesimal number system for measuring time, geographical coordinates and angels, 60 second minute and 60 minute hour, 360 degrees etc.) was safeguarded and further developed ancient knowledge and scientific process during the Golden Age of Islam, leading to the perfection of mechanical clocks and the first watch invention in Nuremberg, a process covering a broad historical stretch of time.[62]
One of the first culture-historical encounter of the Europeans with technology from the Orient was a mechanical water clock from the Abbasid Caliph of Bagdad Harun Al-Rashid (ruled 786 – 809 CE)[63] sent as one of the gifts to the Holy Roman Emperor Charlemagne on the occasion of his coronation in 800 CE, in Aachen[64] The House of Wisdom, an intellectual center in the Caliphates Capital of Baghdad and the Islamic Golden Age started influencing the world civilization and its discoveries, by starting to translate (Translation Movement) and developing ancient knowledge and its discoveries,[65] from one of the most influential texts of all time, Almagest by Ptolemy (AD 100-170), to the influential The Book of Knowledge of Ingenious Mechanical devices by the Muslim polymath Ismail al-Jazari in 1206, describing 100 mechanical devices.[66]
The widespread network of the Muslim Caliphates interconnected with the world's known trade routes, mainly the Silk Road from China to the Caliphate of Cordoba and Al-Andalusian Spain, were not only the most important trade routes but also networks of knowledge transfer.[65] The broad network made it necessary to have primarily navigation devices, such as astrolabes, which were introduced to Europe from Muslim Spain in the early 12th century.[67] The Andalusian engineer Ibn Khalaf al-Muradi wrote the technological manuscript Kitāb al-asrār fī natā'ij al-afkār (The Book of Secrets in the Results of Thoughts).[68] The manuscript provides information about a "Castle and Gazelle Clock" and many other forms of complicated clocks and ingenious devices.[69]
The astronomer and mathematician of the German Renaissance, Regiomontanus who was influenced by the year of Italian Renaissance environment went to Nuremberg and verifiably influenced the circle of humanists and scholars around Peter Henlein. He is famous for building the first observatory in Germany, in Nuremberg.[70] During Peter Henlein’s time at the Franciscan Monastery of Nuremberg, it supported many different scholars and very learned personalities. For example, the monk Friedrich Krafft built a complicated Astrologium in this monastery.[71] Thus Peter Henlein the inventor of the watch not only came into contact with new techniques and tools, but also with a spiritual and intellectual environment of craftsmanship.[29] The earliest medieval European clockmakers were Catholic monks.[72]
The attempt to make clocks smaller and portable was always a challenge for clockmakers, Peter Henlein is not the inventor of portable clocks, but rather of wearable time measurement; the watch, the smallest personalized timekeeping device of his time.[32][73] By combining an Oriental status symbol, the pomander (or fragrance apple), with a miniaturized watch movement, his invention changed the way we measure and manage time.[32] Historically, the watch was crafted at the same time Leonardo da Vinci painted Mona Lisa.[74]
See also
[edit]Literature
[edit]- Ernst von Bassermann-Jordan: Alte Uhren und Ihre Meister, page 47 - 51, publisher: Wilhelm Diebener Leipzig, 1926. German, ISBN 3766704346
- Catherine Cardinal: Die Zeit an der Kette, page 16, publisher: Klinkhardt & Biermann Munich, 1985. German, ISBN 3781402541
- Thomas Eser: Die älteste Taschenuhr der Welt?, publisher: Verlag des Germanischen Nationalmuseums, 2014. German, ISBN 3781402541
- Samuel Guye, Henri Michael: Uhren und Messinstrumente, Orell Füssli Verlag Zürich, 1970. German, ISBN 3894872608
- Maren Winter: Die Stunden der Sammler, Heyne, 2004. German, ISBN 9783548602240
- Jürgen Abeler: In Sachen Peter Henlein, Wuppertaler Uhrenmuseum, Wuppertal 1980. German, ISBN 9783923422234
- Walter Spiegel: Taschenuhren, Mosaik, Munich 1981. German, ISBN 3570055345
- Hans Dominik: Das ewige Herz - Meister Peter Henleins Nürnberger Oerlein, Wilhelm Lippert Berlin, 1942. German, ISBN 9783548360003
- Thomas Eser: Die älteste Taschenuhr der Welt? Der Henlein-Uhrenstreit. Nürnberg 2014. German, ISBN 9783936688924 (Digitalisat)
References
[edit]Footnotes
- ^ Popular quote (Nürnberger Witz) in German: Nürnberger Witz und Tand sind durch die Welt bekannt.[10]
- ^ Popular quote from that time in German: Hätt ich Venedigs Macht und Augsburger Pracht, Nürnberger Witz, Straßburger Geschütz und Ulmer Geld, wär ich der Reichste in der Welt.
- ^ The translation of Johann Cochläus: Peter Hele, still a young man, fashions works which even the most learned mathematicians admire. He shapes many-wheeled clocks out of small bits of iron, which run and chime the hours without weights for forty hours, whether carried at the breast or in a handbag[5]
- ^ No other source can proof an older watch, which was created before - according to older sources, before the watch-reappearance, the previous assumed year of the invention was 1504[20] or 1510[18]
- ^ For the assumption that the first watch could have been created during the time of Henlein's stay in the monastery, there is amongst others also the letter of a nun Felicitas Grundherrin as proof. In it, she expressed the wish to have some „orrlei“ [transl.: watch] to be sent to her for pastime.[29]
- ^ Original quote from Neudörfers 1547: (...) so die kleinen Uhrlein in die Bisam Köpf zu machen erfunden - translated: so invented the little clock to make the muskrat head[57]
- ^ Original words (Walhalla memorial): Erfinder der Sackuhren, Adalbert Müller wrote additionally 1884: Seines Zeichens ein Schlosser, wohnhaft in der seit Jahrhunderten durch Bewerbsamkeit und Erfindungsgeist sich hervortuhenden Stadt Nürnberg[59]
Citations
- ^ a b c Wiebke Neelsen: Das Taschenuhr-Rätsel ist gelöst - Untersuchung Älteste Bisamapfeluhr in einem Neusser Labor, Westdeutsche Zeitung, October 20, 2014, German.
- ^ The oldest watch in the world, YourWatchHub. Retrieved December 7, 2018.
- ^ a b c Television Report (Video), Westdeutscher Rundfunk, German. Retrieved December 7, 2018.
- ^ a b Usher, Abbot Payson (1988). A History of Mechanical Inventions. Courier Dover. p. 305. ISBN 0-486-25593-X.
- ^ a b c d Dohrn-van Rossum, Gerhard; Thomas Dunlap (1996). History of the Hour: Clocks and Modern Temporal Orders. USA: Univ. of Chicago Press. p. 121. ISBN 0-226-15510-2.
- ^ a b c Bisamapfel, Museum für Angewandte Kunst (Cologne), Renate Smolich, 1983, German.
- ^ a b Eric C. Rodenberg: Intricate pomander clock may be the first pocket watch In: AntiqueWeek. The Weekly Antique Auction & Collecting Newspaper 46, Nr. 2326, 2014, p 1, 3.
- ^ Stadtgeschichte, City of Nuremberg, German. Retrieved December 11, 2018
- ^ a b Nürnberg - Stadt der Erfinder und Künstler, Bayerischer Rundfunk, March 28, 2013, German Television Report. Retrieved December 11, 2018
- ^ a b Sebastian Gulden: Wo der "Nürnberger Witz" zu Hause ist, Nordbayern - part of Nürnberger Nachrichten, January 16, 2018. German.
- ^ Konrad Dieterich Haßler: Die BuchdruckerGeschichte Ulm's, Stettin, 1840. German.
- ^ Marco Kirchner: Sagen und Legenden aus Augsburg, John Verlag, German. July 2016, ISBN 9783942057288.
- ^ Milham, Willis I. (1945). Time and Timekeepers. New York: MacMillan. pp. 133–137. ISBN 0-7808-0008-7.
- ^ a b Carlisle, Rodney P. (2004). Scientific American Inventions and Discoveries. USA: John Wiley & Sons. pp. 143. ISBN 0471244104.
watch clock henlein.
- ^ From Cosmographia Pomponii Melae, 1511
- ^ Fanthorpe, Lionel; Fanthorpe, Patricia (2007). Mysteries and Secrets of Time. Dundurn Press. p. 26. ISBN 978-1-55002677-1.
- ^ Reinhard Kalb: Peter Henleins «Dosenuhr» war klein und bequem zu tragen, Nürnberger Nachrichten, German. September 16, 2009.
- ^ a b The first modern-day clock was invented by a locksmith, India Today, April 20, 2018, Retrieved December 7, 2018.
- ^ a b Bisamapfeluhren, renaissanceuhr.de, German. Retrieved December 9, 2018.
- ^ a b Alex Hebra: The Physics of Metrology, Springer Science+Business Media, 2010, p. 57. ISBN 9783211783818.
- ^ Johann Cochlaeus: Cosmographia Pomponii Melae, Nuremberg 1511.
- ^ Eduard Weigert: Weitere Bisamapfeluhr im Rampenlicht, Nürnberger Zeitung (newspaper), German. December 3, 2014.
- ^ Hartmut Voigt: Zank um Zeitmesser - Historische Uhr ist nicht in Henlein-Schau zu sehen, Nürnberger Nachrichten, German. November 14, 2014.
- ^ Nina Pauler, Jutta Olschewski: Wurde das Henlein- Jubiläum verschlafen?, Nürnberger Nachrichten, German. February 2, 2011.
- ^ Ruth Hoffmann: Das gespaltene Reich, Stern (magazine), German. 2006, Nr. 47. ISSN 0039-1239
- ^ Andrew Simms & Ruth Potts: The New Materialism , bread, print & roses, ISBN 9780955226335
- ^ Gudrun Wolfschmidt:Sterne Weisen Den Weg - Geschichte Der Navigation, Beiträge zur Geschichte der Wissenschaft, p. 179, 2009, German. ISBN 9783837039696.
- ^ It's About Time, Museum of Printing (Massachusetts), Richard Romano. Retrieved December 18, 2018.
- ^ a b c Heinrich Lunardi: 900 Jahre Nürnberg - 600 Jahre Nürnberger Uhren, Universitäts-Verglagsbuchhandlung, p. 99 - 113, German. Wien 1974. ISBN 3700300905
- ^ Ulrich Schmidt: Das ehemalige Franziskanerkloster in Nürnberg, Verlag der Nürnberger Volkszeitung, Nürnberg 1913. German.
- ^ Albert Hourani: Der Islam im europäischen Denken: Essays, Fischer Verlag, December 2017. German, ISBN 9783105619520
- ^ a b c d e f g h i j k l The 1505 pomander watch - Research material. Retrieved December 7, 2018.
- ^ Jürgen Abeller: Zeit-Zeichen - die tragbare Uhr von Henlein bis heute, Harrenberger Edition, p. 14–20, German. Dortmund 1983. ISBN 3883793620
- ^ Bruton, Eric, The History of Clocks and Watches, 1979, page 109.
- ^ Birgit Ruf: Stunde der Wahrheit, Nürnberger Nachrichten, December 3, 2014.
- ^ a b Elizabeth Doerr: Is This The World’s Oldest Known Watch? A Peter Henlein Mystery From 1505, Quill & Pad, December 23, 2014. Retrieved December 9, 2018
- ^ Bisamäpfel, Forschungsstelle Realienkunde. German, Retrieved December 12, 2018
- ^ Jacob Cornelisz. van Oostsanen, Web Gallery of Art. Retrieved December 12, 2018
- ^ Ernst von Bassermann-Jordan: Alte Uhren und Ihre Meister, page 47 - 51, publisher: Wilhelm Diebener Leipzig, 1926. German, ISBN 3766704346
- ^ "Apollon, Python". Apollon.uio.no. Archived from the original on 2012-01-19. Retrieved 2012-12-07.
- ^ Robbins, Lawrence H. "AlecC. Campbell, George A. Brook, Michael L. Murphy (June 2007)." World's Oldest Ritual Site? The" Python Cave" at Tsodilo Hills World Heritage Site, Botswana". NYAME AKUMA." the Bulletin of the Society of Africanist Archaeologists (67). Retrieved 1 (2010).
- ^ Malkowski, Edward F. (2007-10-03). The Spiritual Technology of Ancient Egypt p223. Inner Traditions/Bear. ISBN 9781594777769. Retrieved 2012-12-07.
- ^ "Savior, Satan, and Serpent: The Duality of a Symbol in the Scriptures". Mimobile.byu.edu. Archived from the original on 2013-01-29. Retrieved 2012-12-07.
- ^ Linda Alchin: Circle of Ouroboros, Mummies2Pyramids. Retrieved December 20, 2018.
- ^ De Cleene, Marcel; Lejeune, Marie Claire (2003). Compendium of symbolic and ritual plants in Europe, Volume 1. Man & Culture. p. 129. OCLC 482791069.
- ^ Pliny the Elder. Natural History Book XV.39.
- ^ Annette Giesecke (2014). The Mythology of Plants: Botanical Lore from Ancient Greece and Rome. J. Paul Getty Museum. pp. 35–36.
- ^ Pliny the Elder. Natural History Book XV, 35.
- ^ Madanjeet Singh: The Sun: Symbol of Power and Life, Harry N Abram, 1993. ISBN 9780810938380
- ^ Bazzicchi, Oreste (2011). Il paradosso francescano tra povertà e società di mercato. Effatà Editrice. p. 98. ISBN 978-88-7402-665-4.
- ^ Campbell, Gordon (2006). The Grove Encyclopedia of Decorative Arts, Vol. 1. London: Oxford University Press. pp. 250–251. ISBN 0195189485.
- ^ 3D animation of the Pomander Watch from 1505, the world's oldest known watch (Video), TPW Prüfzentrum, retrieved December 7, 2018.
- ^ Jülich: Vermutlich älteste Taschenuhr der Welt aus dem Jahre 1505 entdeckt, City of Cologne, German. September 13, 2007.
- ^ Horolosieal Exposition at Nuremberg, Scientific American, Volume 92 Number 18 (May 1905).
- ^ Der Peter-Heinlein-Brunnen in Nürnberg, Nürnberg.Bayern-online.de, German. Retrieved December 9, 2018.
- ^ Nürnberger Kunststücke, Traumwanderungen.de, German. Retrieved December 10, 2018.
- ^ a b Gerhard Dohrn-Van Rossum: Die Geschichte der Stunde, Carl Haner Verlag Munich 1992, p. 119, German. ISBN 3446160469.
- ^ Official Guide booklet, 2002, p. 3
- ^ a b Adalbert Müller: Donaustauf und Walhalla, German, 1844.
- ^ Spherical Table Watch (Melanchthon's Watch), Walters Art Museum. Retrieved December 7, 2018.
- ^ Jürgen Abeler: In Sachen Peter Henlein, Wuppertaler Uhrenmuseum, 1980. German. ISBN 9783923422234.
- ^ Mesopotamian Astronomy, https://explorable.com/. Retrieved December 20, 2018.
- ^ T.M.P. Duggan: On the Tradition of Islamic Figural Sculpture to 1300, Mediterranean Journal of Humanities, p. 61 - 86.
- ^ Water Clock, Aljazaribook. Retrieved December 20, 2018.
- ^ a b Isabella Bengoechea: Iraq’s Golden Age: The Rise and Fall of the House of Wisdom, culturetrip, September 9, 2016. Retrieved December 20, 2018
- ^ Ismail al-Jazari: The Book of Knowledge of Ingenious Mechanical Devices.
- ^ John M. Hobson (2004), The Eastern Origins of Western Civilisation, p. 141, Cambridge University Press, ISBN 0521547245.
- ^ Ahmed Djebbar: "Technology in the service of progress: The examples of hydraulic technologies," in Civilization in the Mirror of Universal, UNESCO, 2010, p. 292-304.
- ^ Koenraad Van Cleempoel. "The Migration of Instrumental Knowledge from Flanders to Spain," in: Silent Messengers: The Circulation of Material Objects of Knowledge in the Early Modern Low Countries, Sven Dupré and Christoph Herbert Lüthy (eds.), (Transaction Publishers, 2011), p. 76.
- ^ Johannes Regiomontanus: Calendar, University of Glasgow, August 9, 1482.
- ^ Claudia Krüll (1980), "Krafft, Friedrich", Neue Deutsche Biographie (in German), vol. 12, Berlin: Duncker & Humblot, pp. 643–644
- ^ Harald Kleinschmidt: Understanding the Middle Ages, Boydell & Brewer p. 26. ISBN 9780851157702
- ^ Karla Eckert: Eine Laune. Das Verlangen, die verrinnende Zeit zu messen, ist zeitlos., Tagesspiegel, German. September 17, 1994.
- ^ Pedretti, Carlo (1982). Leonardo, a study in chronology and style. Johnson Reprint Corporation. ISBN 978-0384452800.