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HENRY, JOSEPH - THE DISCOVERY OF SELF-INDUCTION - GERMAN VERSIONBiblio.com

JANSSEN, PIERRE JULES CESAR - THE DISCOVERY OF HELIUM IN THE SUNBiblio.com

Éclipse de Soleil du 18 Aout 1868. Rapport adressé par M. Janssen au Maréchal de France Président du Bureau des Longitude.

187844231Paris G. Masson 1878. 8vo. Contemp. hcalf raised bands gilt spine. Light wear along edges. Small stamps on verso of titlepage. In: "Annales de Chimie et de Physique" 4e Series - Tome 15. 512 pp. a. 3 folded engraved plates. The entire volume offered. Janssen's memoir: pp. 414-426. First appearance of this milestone paper in chemistry physics and astronomy announcing the discovery of the helium lines in the spectrum of the sun. It was Lockyer in the same year that named it 'helium' for Helios the Greek God of the Sun. Helium was not discovered on the earth before 1895 by William Ramsay and it was Crookes who established its identity with the helium Janssen and Lockyer observed in the spectrum of the sun."He Janssen met immortality by travelling to India in 1868 to study the total eclipse. It was then that he observed the helium line and forwarded the spectral data to ockyer. He also noted the size of the solar prominences. The day after the eclipse he attempted to take their spectra again and succeeded despite the absence of the obscuring moon. he then announced jubilantly that it was the day after the eclipse that was the real eclipse day for him. Lockyer also reported this method of studying prominences without an eclipse.Like Lockyer he lived to see his observation of the helium line vindicated by Ramsay's discovery of that element on earth."Asimov."This the discovery of helium lines in the sun by Lockyer was announced on the same day by the French astronomer Janssen who was in India observing a total eclipse. As a result the French government some ten years later struck a medallion showing the heads of both scientists.By that time the two men had made a much more dramatic discovery at the same time this time in cooperation. Janssen studying the spectrum ofthe sun during the eclipse had noted a fine line he did not recognize. he send a report on this to Lockyer an acknowledges expert on solar spectra. Lockyer compared the reported position of the line with lines of known elements concluding that it must belong to a yeat unknown element possibly not even existing on the earth. He named the element from the Greek word for the sun."Asimov.Parkinson "Breakthroughs" 1868 A. - The volume contains other notable papers by Dumas Berthelot et al. hardcover

Herman H. J. Lynge & Søn A/S · Danemark7 500,00 DKK≈ 1 007,25 €

JOHN HARRISON AND THE DISCOVERY OF LONGITUDEBiblio.com

A 1765 account of John Harrison on discovering longitude at sea using artificial timekeepers from the Annual Register for 1765

1793373234J. Dodsley London 1793. 5th Edition. Hardcover. Very Good Condition. 21 pages. This 1765 article published in The Annual Register provides a detailed account of John Harrison's groundbreaking work in solving the longitude problem at sea through the use of artificial time-keepers. Harrison an English clockmaker developed the marine chronometer a device that allowed sailors to accurately determine their longitude while at sea. His invention was crucial for safe navigation reducing the risk of ships becoming lost or wrecked due to miscalculations. The article outlines the proceedings and debates surrounding Harrison's work including his struggles with the Longitude Board which was reluctant to grant him the full 20000 prize promised under the 1714 Longitude Act. Despite proving the accuracy of his time-keepers Harrison faced political opposition and bureaucratic delays before finally receiving recognition for his achievements. Published at around the same time that Harrison's book of a similar title was published this contemporary 21 page account quotes Harrison extensively and represents the opinions and ideas regarding navigation from the perspective of the time. The whole volume extends to around 600 pages. Bound in modern but not recent brown buckram with a contrasting black leather lettering piece gilt title. Library label to the endpapers stamp on first blank and label to reverse of the title page. The first blank has a hand note stating "Given by Lt.Col. A.R. Hurst". Hurst has served with the Royal Field Artillery in the First World War. The whole volume is very clean with bright pages very firmly bound and in attractive condition. Size: 13.5 x 21 cms. Category: Antiquarian & Rare; Featured Items; Printed before 1800; Special Features. This item may require more postage than the rates shown for delivery outside the UK. If extra postage is required we will contact you before processing your order and you will be given the details and option to decline the extra cost. J. Dodsley hardcover

Cosmo Books · Royaume-Uni209,80 £GB≈ 239,55 €

LECOQ de BOISBAUDRAN, PAUL EMILE - ANNOUNCING THE DISCOVERY OF THE ELEMENT GALLIUMBiblio.com

Caractéres chimique et spectroscopiques d'un nouveau métal le Gallium découvert dans une blende de la mine de Pierrefitte vallée d'Argelès Pyrénées. Séance du Lundi 20 Septembre 1875. Sur quelques propriétés dy gallium. Séance du Lundi 6.

187547271Paris Gauthier-Villars 1875. 4to. No wrappers. In: "Comptes Rendus Hebdomadaires des Séances de L'Academie des Sciences" Tome 81 No 12 and No 23. Pp. 485- 508 a. 1065- 1148. 2 entire issues offered. Boisbaudran's papers: pp. 493-495 a. pp. 1100-1105. First printing of the paper in which Boisbaudran announced his discovery of Gallium together with the first printing of the paper in which he by a series of experiments proved that Gallium the metal that he had discovered amd named in honour of France is a true element. A larger paper on the discovery was published in 1877 in "Annales de Chimie et Physique". In 1879 Bausbaudran was awarded the Davy Medal for his discovery of Gallium. "In 1875 Boisbaudran spectroscopically discovered a new element gallium which he found in zinc blende from a mine in Hautes-Pyrénées. Continuing his work in Wurtz’s laboratory in Paris he was a able to obtain the free metal by electrolysis of a solution of the hydroxide in potassium hydroxide. Gallium Boisbaudran realized was the "eka-aluminum" predicted by Mendeleev and was the first of Mendeleev’s predicted elements to be isolated. Boisbaudran’s finding thus provided valuable evidence for the validity of Mendeleev’s periodic classification of the elements."DSB."Lecoq de Boisbaudran announced his discovery by spectroscopic analysis of the new element gallium. Mendeleev had first predicted its existence and had named it eka-aluminium. The discovery was made in the author's private laboratory in a specimen of zinc blende from the Pierrefitte mine in the Angelès Valley in the Hautes Pyrénées. He describes how on the evening of 27 August 1875 he detected the existence of this new element which he named "gallium" in honor of France Gallia. A month later he "performed in Wurtz's laboratory in Paris.a series of experiments to prove that gallium.is a true element"Weeks. he discusses how he eventually isloated small amounts of pure metallic gallium and determined its physical and chemical properties. The paper the paper offered first describes gallium compounds e.g. ammonium gallium alum chloride oxide and sulphate."Roy G. Neville II p. 29. unknown

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LEIBNIZ (LEIBNITZ), GF - CHRISTIAAN HUYGENS - JOHANN BERNOULLI - JACOB BERNOULLI ET AL - THE DISCOVERY OF THE "CATENARY CURVE"Biblio.com

1. De Linea in quam Flexile se pondere proprio curvat ejeuque usu insignia adinveniendi quotcunque medias proportionales & Logarithmos. - 2. De Solutionibus Problematis Catenarii vel Funicularis in Actis A. 1691 aliisque a Dn. I.B. propositis. 1-2:.

169141859Leipzig Grosse & Gleditsch 1691. 4to. Contemp. full vellum. Faint handwritten title on spine. a small stamp on titlepage. In: "Acta Eruditorum Anno MDCLXXXXI". 85906 pp. and 13 of 15 folded engraved plates. The 2 first plates lacks but they do not belong to the papers listed.Leibniz' papers: pp.277-281 a. 1 plate pp. 435-439. Johann Bernoulli: pp. 274-276 a. 1 plate. Huygens: pp. 281-282. - Jacob Bernoulli: pp. 282-290 a. 1 plate. All papers first apperance. All 5 of extreme importence in the development of the Calculus. Leibniz' 2 papers on the catenary curve paper 1-2 offered here was written at the instigation of Jacques Bernoulli. Following the example of Blaise Pascal who had initiated in 1658 a contest for the construction of the cycloid Leibniz also provoked the geometers of his time by challenging them to submit at the fixed date of mid-1691 their geometric method for the construction of the catenary curve. Leibniz later provided the answer followed by Johann Bernoulli and Huygens.'These two papers are a historical account of the origin of the study of this transcendental curve and at the same time the first physical-geometric construction showing the species-relationship between the catenary and the logarithmic curves as two companion curves; one arithmetic the other geometric. All of the differentials of the catenary curve are arithmetic means of corresponding differentials of the logarithmic curve; and all of the differentials of the logarithmic curve are geometric means of the catenary.'"The Catenary is the form of a hanging fully flexible rope or chain the name comes from "catena" which means 'chain' suspended on two points. The interest in this curve originated with Galileo who thought that is was a parabola. Young Christiaan Huygens proved in 1646 that this cannot be the case. What the actual form was remained an open question till 1691 when Leibniz Johann Bernoulli and the then much older Huygens sent solutions to the problem to the "Acta" Jakob Bernoulli 1690 Johann Bernoulli 1691 Huygens 1691 and Leibniz 1691 - these 4 1691-papers offered here - in which the previous year Jakob Bernoulli had challenged mathematicians to solve it. As published the solutions did not reveal the methods but through later publications of manuscripts these methods have been known. Huygens applied with great paper 4 virtuosity the by then classical methods of 17th century infinitesimal mathematics and he needed all his ingenuity to reach a satisfactory solution. Leibniz the papers 1-2 and Bernoulli paper 3 applying the new Calculus found the solutions in a much direct way. In fact the catenary was a test-case between the old and the new style in the study of curves and only because the champion of the old style was a giant like Huygens the test-case can formally be considered as ending in a draw." Grattan-Guiness in "From the Calculus to Set Theory 1630-1910.".The paper by JACOB BERNOULLI no. 5 offered here is a milestone papers as it marks the invention of the "SYSTEM OF POLAR COORDINATES" with points located by reference to a fixed point and a line through that point. Although newton had earlier also devised such a coordinate system in 1671 his work was not known so that the credit for the discovery generally goes to Bernoulli. Parkinson Breakthroughs 1691.Further papers contained in this volume of Acta Eruditorum:DENYS PAPIN: Mecanicorum de Viribus Motricibus sententia asserta a D. Papino adversius C.G.G. L. Leibniz objectiones. pp. 6-13. The plate lacks. - and Dion. Papini Observationes quaedam circa materias ad Hydraulicam spectantes. Pp. 208-213 a. 1 plate. This importent paper is part of the LEIBNIZ-PAPIN-CONTROVERSY.JACOB BERNOULLI: Specimen Calculi Differentialis in dimensione Parabolæ helicoidis ubi de flexuris curvarum in genere carundem evolutionibus. Pp. 13-22. The plate lacks. - and J.B. Demonstratio Centri Oscillationis ex Natura Vectis reperta occassione eorum quæ super hac materia in Historia Literaria Roterodamensi recensentur articulo.Pp.317-321.LEIBNIZ: O.V.E. Additio ad Schediasma de Medii Resistentia publicatum in Actis mensis Febr. 1889. Pp. 177-178. and O.V.E. Quadratura Arithmetica Communis Sectionum Conicarum quæ centrum babent.Pp. 178-182 a. 1 plate.TSCHIRNHAUS: Singularia Effecta Vitri Caustici bipedalis quod omnia magno sumtu hactenus constructa specula ustoria virtute superat per D.T. Pp. 517-520 hardcover

Herman H. J. Lynge & Søn A/S · Danemark25 000,00 DKK≈ 3 357,50 €