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The decision to go to the Moon was made much sooner than September 1962. In his Special Message to the Congress on Urgent National Needs made on 25 May 1961, President Kennedy announced that I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the earth. ...

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Unlike the short-range rockets which are all solid fueled, making a solid-fuel long range rocket is very challenging. The main technical problem is that the fuel block which is very large can develop a crack under mechanical and thermal stress. The flame will immediately spread into the crack, and the whole thing will explode. The second difficult problem ...

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The transition that occurred took place outside of mathematics, although it eventually affected mathematical practice and teaching. Seidenberg documents early construction practices that used pegs and ropes, and the traditional story is that Pythagoras learned geometry from Egyptian rope-stretchers. The story is not very credible, but it testifies to the ...

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It was a theoretical invention. A special case, optimal elliptic transfer between two circular orbits, a.k.a. the Hohmann transfer, was described by Hohmann in The Attainability of Heavenly Bodies (1925), see Washington: NASA Technical Translation F-44, 1960 on Internet Archive. It is accomplished by two burns, one prograde one retrograde. Hohmann, ...

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lmgtfy google cache of mimivanderhave.com 1945 The first double-pane, insulated window was introduced That's without attribution; door and window claims From single to double pane windows… The true evolution of double pane windows originated in 1913 when the Andersen Lumber Co. became the first to manufacture wood window frames. In 1932 they ...

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No, Pasteur did not invent swan necked bottles, he only invented a novel use for them as described in the quote. Venetian craftsmen produced swan necked glass bottles for decorative purposes back in 16th century. They were imported to Iran under the reign of Shah Abbas I (1587–1629) and became a traditional glassware there, the Persian name is ashkdān. Their ...

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Jazari is referring to "an Arabic treatise of unknown date and authorship" that describes a monumental water-clock. It is not listed among Archimedes's works in any ancient sources, and according to Hill, most of it was written by several Arabic authors. The "author" is now referred to as Pseudo-Archimedes. Ridwan al-Saati built Jayrun water clock based on ...

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There seems to be little secondary literature on this so answering the OP questions fully would take some serious digging into the original sources. One promising secondary source that I was unable to locate is Ceccarelli and Koetsier, Burmester and Allevi: A Theory and its Application for Mechanism Design at the end of 19th Century, Proceedings of IDETC/CIE ...

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In answer to your second part of the question regarding $j$ for $\sqrt{-1}$, this was introduced into text books describing Power System Analysis of AC power circuits in the early 1900s by Charles P. Steinmetz. I am not sure of the earliest date but my guess is between late 1890s and 1920s but certainly no later than 1923 as Steinmetz died in 1923. ...

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This question has been discussed on Math overflow: https://mathoverflow.net/questions/116627/useless-math-that-became-useful/116653#116653 This is about conic sections in general. In my answer I gave them as example of "useless mathematics which became useful centuries later". Some tried to challenge this statement. One of the conjectures mentioned that ...

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I am not going to trace back to the antiquity the whole history of ellipses and the instruments that drew them; I trust that more knowledgeable users would comment on Meneachmus, Proclus and others. Instead, let me offer some clear purpose for which ellipses were (and still are) used, namely for depicting circles in perspective in paintings and drawings. One ...

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One of the most important contributions of Latins to engineering was road-building. This certainly pre-dates contacts with the Greek civilization: so called "strade consolari" departing from Rome (thus the Italian way of saying "all roads lead to Rome") and connecting the principal area of Italy were built already starting from the early Latin period (when ...

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Brunel (1806-1859) in 1822 was a candidate to the École Polytechnique. Augustin-Louis Cauchy (1789-1857) graduated in civil engineering and in 1816 was appointed professor at École Polytechnique. The seminal Cours d'Analyse was published by Cauchy in 1821 as Cours d'Analyse de l’École Royale Polytechnique. On this ground, we have to presume that the ...

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I doubt it that the $i$ notation would have been used for $\sqrt{-1}$ before Euler because even Euler himself did not start using it until a rather late date, and moreover used $i$ in a different sense namely for an infinite integer, in his Introductio and Institutiones.

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The engine in question does not lift water; rather it pushes water up from the bottom of the vessel. As is clearly shown in the animated image here, condensed steam is forced into the bottom of the lifting pipe. A freeze-frame from that page: So long as the combination of partial vacuum in the cylinder (as steam condenses into liquid) and the net mass (...

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