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  • Jesuits and the Early Telescope:Scheiner and Grienberger
    telescope see Reflecting on History The Jesuits unorthodoxy also extended to how they used telescopes Scheiner like several other scientists of his day was very interested in viewing sunspots He decided against the dangerous approach of viewing these sunspots directly through a telescope Instead he chose to view the image projected from the telescope This was Scheiner s famous helioscope Amazing as it might seem today he also built a heavy camera like device a camera obscura and positioned it behind his telescope The image below from a copy of the Rosa Ursina at Queen s University shows how the telescope was used as part of a camera obscura These innovations and those of another Jesuit a Father Grienberger resulted in the finest celestial images during Galileo s lifetime the plates of the sunspots in Father Scheiner s Rosa Ursina Sometimes technological advances bring new problems and cause further technological breakthroughs Scheiner s helioscope was heavier and more complex than other telescope configurations His configuration of telescope and camera obscura was much heavier It was necessary to develop a practical way of tracking celestial bodies in spite of the weight and complexity Another Jesuit Father Grienberger developed a way of mounting telescopes called an equatorial mount which made it possible to track a star by altering position in only one axis The other mounts required altering the telescope position in two axes Even today this mount is considered superior for any serious amateur astronomer and a must for astro photography Newton considered Scheiner s work on optics important enough to obtain a personal copy for his library 4 The Jesuits also have a connection with the spread of telescope technology beyond Europe The first telescope in North America was a gift presented by the Jesuits in 1646 to Jean Bourdon an engineer in New France modern day Quebec 5 The first telescope in China was brought there by Johannes Schreck another Jesuit in 1621 his trip from Europe started in 1618 6 The Jesuit Jean Richaud is wrongly thought to be the first to use telescopes for astronomical purposes in India That honour goes to Jeremiah Shakerley in 1651 Regardless the contributions to astronomy from his early use of the telescope are notable These include observations of a comet and the discovery that the bright star in Alpha Centauri was actually a double star 7 The first telescope in the American colonies was thought to have arrived in the 1660 s and the first telescope in the New World was probably brought over by Portugese mariners in 1614 a telescope was mentioned in records of the battle of Guaxanduba Brazil Copyright Joseph Sant 2015 Cite this page APA Sant Joseph 2015 Jesuits and the Early Telescope Scheiner and Grienberger Retrieved from http www scientus org Jesuits Telescope html 1 van Helden Albert The Telescope in the Seventeenth Century in Isis Vol 65 No 1 Mar 1974 46 van Helden states Moreover the Galilean telescope placed an upper limit on magnification

    Original URL path: http://www.scientus.org/Jesuits-Telescope.html (2016-02-10)
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  • The Early Reflecting Telescope:Cassegrain, Mersenne, and Cavalieri
    s diagrams of his telescopes image was taken from 3 There is a side story to Mersenne s and Cavalieri s works Harmonie Universelle was a book about music but it is important to the history of telescopes Lo Specchio was a book about mirrors and telescopes but is probably more important to the history of classical mechanics Lo Specchio contained the first published description of the parabolic nature of projectile motion Cavalieri s publication of this important concept even caused a short lived rift in his friendship with Galileo Galilei Both Galileo Galilei and Thomas Harriot had described projectile motion in private notes but had never published Mersenne s work on reflecting telescopes was very advanced Today it is doubted that either he or any of his contemporaries including Descartes and Galileo understood the full significance of his work A full understanding of the advanced nature of Mersenne s work would have to wait until the twentieth century An indication of this is that the Mersenne telescope still being produced today is largely a development of the twentieth century Mersenne went further than simply presenting configurations that are used in modern telescopes his designs featured the strong telephoto effect critical to modern photographic lenses This all happened 30 years before Newton s telescope 4 Mersenne actually never did build telescopes to his designs Oddly he was dissuaded from building them by Rene Descartes Descartes felt that reflecting telescopes were impractical Given the technology of the day he was correct It would be more than a century before reflecting telescopes were competitive with refractors The mirrors of the time were made of polished metal which tended to tarnish Also the tolerances for mirrors is four times more critical than for lenses 5 Why are Mersenne s contributions ignored It is difficult to find his name in popular histories of the telescope Mersenne was widely considered to be the inventor of the reflecting telescope in the nineteenth century Several nineteenth century encyclopedias including the Encyclopedia Americana identified Mersenne as the inventor of the reflecting telescope Others if they did not credit him with the invention of the reflecting telescope did mention his contribution to its early development see Google Books Mersenne fell from grace in the twentieth century Mersenne was not even mentioned in a 1943 survey of the early development of the telescope by the historical journal Isis 6 The importance given to a historical figure sometimes depends as much on the dominant biases of the day as on their contributions see Sarton A Case for Bias M Cassegrain Man without a Name On April 15 1672 the Journal de Scravans published an excerpt of a letter from a M de Berce describing a telescope design proposed by a M Cassegrain It had a large primary concave mirror which reflected light onto a smaller secondary convex mirror which then reflected the light back through a hole in the primary mirror to an eyepiece The diagram that was used to illustrate

    Original URL path: http://www.scientus.org/Reflecting-Telescope-History.html (2016-02-10)
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  • Timeline of Telescopes and Lenses

    (No additional info available in detailed archive for this subpage)
    Original URL path: /timeline/telescope.html (2016-02-10)


  • The Real da Vinci Code
    The da Vinci Codices What was in the Da Vinci Codices that was so threatening It was the Parisian Doctors This was a group of priests and bishops from the fourteenth century that had written extensively on classical mechanics They had formulated Newton s First Law of Motion almost three hundred years before Newton had 3 They had defined constantly accelerated motion centuries before Galileo Galileo s description and geometric proof of the Odd Number Rule was largely the same as those of the Parisian Doctor Bishop Oresme Galileo did know of the Parisian Doctors work We know this Galileo s own writings that he was aware of the Doctors work There was another threat posed by the Doctors There was a direct line from the Parisian Doctors to another group the Oxford Calculators see The Calculatores This was another group of priests and bishops studying classical mechanics They had developed the mean speed theorem centuries before Galileo had proposed it see How original is Galileo s work on kinematics Science and Censorship The answer to the Duhem Problem was to censor his work Academic conspiracy theories sound no more believable than the Da Vinci Code s Priory of Sion a twentieth century hoax that Dan Brown brought to life in his novels But the academic censorship of Duhem s work has credible witnesses Duhem s publisher Hermann et Cie refused to publish the final volumes of his Systeme du Monde The excuse given was financial hardship The real reason why Duhem s work would not be published was divulged by an insider into the workings of the French scientific establishment the head of the Institute d Histoire des Sciences at the Sorbonne Abel Rey It was not financial concerns Hermann et Cie was being pressured by very powerful anti clerical elements in government and academe not to promise publication of his work The information in the manuscripts was not something they wanted published His works showed that significant advances in the science of mechanics had occured well before the Scientific Revolution and during a time when the church was the central influence on society 4 Abel Rey is one of the heroes of the story Abel Rey was himself anti clerical This did not stop him from supporting Helene Duhem s 40 year long fight to publish her father s last works The censorship didn t stop with a hostile publisher Duhem had crossed the line with the second volume of the System du Monde George Sarton the editor of Isis believed strongly that Science and Christianity conflict Duhem name would rarely be mentioned in Isis while Sarton was editor Sarton allowed the publication of a virulent personal attack on one of the giants of the history of science by a graduate student The student even suggested that one of the great physicists of the late nineteenth century didn t fully grasp the physics he was discussing 5 Sarton like Duhem was a specialist in Medieval History Some of

    Original URL path: http://www.scientus.org/Real-DaVinci-Code.html (2016-02-10)
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  • Sarton, History and Bias
    borders Thomas Bradwardine was so famous that he had even been mentioned in Geoffrey Chaucer s The Canterbury Tales In that work he had been placed in league with the greatest philosophers St Augustine and Boethius Bradwardine and a follower of his school Paul of Venice had also received the greatest honor possible for a medieval academic being bestowed with a special surname Bradwardine had received the honorary title doctor profundus and Paul of Venice had received the name doctor profundissimus Overlooking these three figures in a treatment of medieval science would be like overlooking Einstein in a treatment of 20th century science Medieval physics was downplayed in spite of its direct relevance to later advances The Calculatores had proposed the mean speed theorem This was supposed to be one of Galileo s important contributions to science Jean Buridan had proposed a theory of impetus very similar to Galileo s own impetus theory This would eventually be refined by Newton into the theory of inertia There was one article written in German in Isis devoted to Thomas Bradwardine an important Calculatore and and none to Jean Buridan Buridan was mentioned in a 16 page survey of physics that covered all physics over the entire middle ages 4 The journal s treatment of early modern science poses some problems as well One scientist from this period was Father Domingo De Soto He had published the correct law of free fall in the mid sixteenth century 75 years before Galileo s important works on mechanics It is amazing how little interest there was in the first author to publish such an important theorem This in spite of the fact that Duhem had discussed his work in the early twentieth century 5 It is now known that the De Soto s Physics which outlines the correct law of free fall was already in its eight edition during Galileo s university days at Pisa De Soto s Physics was being read and taught Galileo may even have been told the correct law of free fall De Soto s work was commonly taught in Jesuit schools in Italy and other parts of Europe before Galileo finally decided on the correct law of free fall in Padua Galileo is known to have corresponded with Jesuit scientists while at Padua 6 Copyright Joseph Sant 2015 Cite this page APA Sant Joseph 2015 Sarton History and Bias Retrieved from http www scientus org Sarton Isis html 1 JStor JStor JStor Search Engine The JStor search engine is a service available which allows you to search and retrieve a wide variety of academic e journals It allows a user to search 11 different journals on the History of Science and Technology including Isis A search was done for articles in Isis with any reference to Duhem between 1912 to 1952 There was a total of 36 hits Most of these articles had only cursory mention of his name or work This averages 1 article referencing his name per year

    Original URL path: http://www.scientus.org/Sarton-Isis.html (2016-02-10)
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  • George Sarton, Isis and Historian Bias
    book was virulently anti Christian and anti Catholic Worse with regard to George Sarton is that the book was never credible The book referenced events from a historical fiction of Christopher Columbus written by the popular fiction author Washington Irving as fact George Sarton s strong anti church bias is not a problem on its own Historians are human Scientists have their biases too Scientific methods are not intended to eliminate the researcher s bias which is impossible but to neutralize the effect of these biases on the final results of the research Besides if a case can be made that George Sarton had an anti church bias an equally good case could be made that another historian of his era Pierre Duhem had a pro church and pro french bias And it would also be naive to think that modern historians do not have biases There are differences between George Sarton Pierre Duhem and modern historians that do make his bias very important George Sarton was much more than a historian of science He was the father of the history of science and he guided the profession through its early years He was the editor of the most important English language journal on the history of science Isis He was also an important educator He had a tremendous influence on what was studied and what was published during his lifetime The situation was different with Pierre Duhem Pierre Duhem was only a historian of science and a thermodynamicist and a philosopher of science not an editor or educator He had no control over the publication of others people s work or what research they followed Modern historians of science are different too They are working in a mature field with several reputable journals and where multiple biases are tolerated

    Original URL path: http://www.scientus.org/Sarton-Isis-Bias.html (2016-02-10)
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  • The Church and the Early Telescope
    that the priests contribution to the development of the early telescope was never mentioned in the program or on the accompanying website see Galileo s Battle for the Heavens The Matthew Effect is a tendency discussed by historians where credit for discoveries or inventions is incorrectly attributed to already famous scientists There is probably no better example of this effect than the history of the early telescope There were many scientists who made critical contributions to the development of the early telescope see Timeline of the Telescope Popular histories typically only discuss two Galileo and Newton Those excluded include famous thinkers such as Kepler and Descartes and several Roman Catholic priests There were several advances in theoretical optics and telescope construction during Galileo s lifetime that would impact the development of telescopes for centuries to come Oddly Galileo was not involved in any of these advances His importance to the history of the telescope lies in the fact that he made the use of telescopes respectable in science This on its own is a very important contribution His skill as an artisan especially polishing lenses also resulted in telescopes that were a considerable improvement over those that preceded him Florence Galileo s birthplace had been the pre eminent center for lens making in Europe since the late thirteenth century see Timeline of the Telescope Year 1289 But beyond this it is difficult to name one advance made by Galileo in the theory or construction of telescopes that is in use today That is not true of the church scientists of his day especially the Jesuits The scientists who had the greatest influence on the future of optics and telescope construction from Galileo s day were Johannes Kepler Rene Descartes Wilebrord Snell Father Marin Mersenne Father Bonaventura Cavalieri Father Christopher Scheiner and Father Christopher Grienberger The first three developed a theoretical foundation for refraction and reflection that would be built upon in the following centuries The four fathers made critical contributions to the technology of telescopes All of their contributions are still in use today Fathers Marin Mersenne and Bonaventura Cavalieri together would propose the basic geometric shape that would be used in modern reflecting research telescopes see Reflecting on History Father Christopher Scheiner a Jesuit would be the first to construct a modern astronomical telescope using theory proposed by Johannes Kepler Christopher Grienberger a Jesuit colleague of Scheiner s would propose an extremely sophisticated method of mounting telescopes to better follow celestial bodies as they arc through the night sky Father Scheiner would use Grienberger s equatorial mount to produce the finest celestial images of the early seventeenth century The contributions of Father Nicolo Zucchi another Jesuit may not have been as important as the scientists listed above but he was able to demonstrate that using telescopes combining lenses and mirrors was viable This was in 1616 50 years before Newton s famous reflecting telescope He was the master craftsman who also built refracting telescopes for Johannes Kepler at the

    Original URL path: http://www.scientus.org/Telescope-Scheiner-Cassegrain.html (2016-02-10)
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  • Timeline of Classical Mechanics and Free Fall
    Methodologists The Calculatores New Medieval Universities Timeline Galileo s Battle for the Heaven s Galileo s Twin Galileo and the Elephant Stellar Parallax Timeline of Mechanics Galileo s Contemporaries Duhem The DaVinci Code Sarton A Case for Bias Sarton The Isis Files Timeline of Classical Mechanics and Free Fall To move timeline left or right drag either top or bottom band 901BC 801BC 701BC 601BC 501BC 401BC 301BC 201BC 101BC

    Original URL path: http://www.scientus.org/timeline/classical-mechanics.html (2016-02-10)
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