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Artigo Acesso aberto

Smithson Tennant,

... Isaac Newton having observed that inflammable bodies had a greater refraction, in proportion to their density, than ... diamond was capable of resisting the effects of a violent heat when the air was carefully excluded, ... remained to be determined whether the diamond was a distinct substance, or one of the known inflammable ... this question till M. Lavoisier, in 1772, undertook a series of experiments for this purpose. He exposed the diamond to the heat produced by a large lens, and was thus enabled to bum ...

Tópico(s): Historical and Literary Studies

1797 - Royal Society | Philosophical Transactions of the Royal Society of London

Artigo Acesso aberto

Edward Pigott, Henry Englefield,

... by determining their periodical changes of light, established a strong affinity between them and our sun; and ... with changes perhaps even sufficiently rapid to afford a ready means for determining accurately differences of terrestrial longitudes. This would be a most satisfactory, useful, and profitable discovery, and may be the lot of those who have but a slight knowledge of astronomy, provided that with great exactness, and a good memory, a constant look out be given. The discoveries which , ... Crown . The constellation of Sobieskiʼs Shield consists of a very few stars, and was formed by Hevelius, ...

Tópico(s): Historical and Architectural Studies

1797 - Royal Society | Philosophical Transactions of the Royal Society of London

Artigo Acesso aberto

Alessandro Volta,

... d'un professeur de Bologna, Mr. Galvani, qui a paru il y a à-peu-près un an, avec ce titre; Aloysii ... autres celui du Dr. Brugnatelli de Pavie, qui a pour titre, Giornale Fisico-medico; auquel j'ai ... Banks. pour être communiqué, s’il le croit à propos, à cette savante Compagnie, corame un foible temoignage de ma reconnoissance pour 1'honneur qu’elle m’a fait de m’associer à son corps, et de inon zele et empressement à répondre à son invitation de lui faire part, de terns ...

Tópico(s): Neurology and Historical Studies

1793 - Royal Society | Philosophical Transactions of the Royal Society of London

Artigo Acesso aberto

Thomas Young,

... which are supposed to be the results of a uniform tension of a surface, resisting the pressure of a fluid, either uniform, or varying according to a given law. Segner, who appears to have been the first that maintained a similar opinion, has shown in what manner the ... is evidently the cause of the want of a perfect coinci­dence of some of his experiments ... experiment; that is, that for each combination of a solid and a fluid, there is an appropriate angle of contact ... glass and water, and in all cases where a solid is perfectly wetted by a fluid, is ...

Tópico(s): Advanced Thermodynamics and Statistical Mechanics

1805 - Royal Society | Philosophical Transactions of the Royal Society of London

Artigo Acesso aberto

George Rennie,

... considered as deviating from my subject, ill taking a cursory view of the labours of others.The ... it deserves our serious attention.The passage over a deep and rapid river, the coustruetion of a great and noble edifice, or the combination of a more complicated piece of mechanism, are arts so ... writers are founded, have given rise to such a multiplleity of contradictory conclusions, that it is difficult ... us.Emerson, in his Mechanics, has'laid down a number of rule~ and approximations.Professor Robison in ...

Tópico(s): Historical Philosophy and Science

1819 - Taylor & Francis | The Philosophical Magazine

Artigo Acesso aberto

Thomas Young,

... on the methods of appreciating the accuracy of a long series of observations in general, I have ... I have obtained from my investigations, in such a form as might serve either to accompany the ... to be laid before the Royal Society as a distinct communication. 1. On the estimation of the advantage of multiplied ob­servations . It has been a favourite object of research and speculation, among the ... accuracy of experimental re­sults, maybe reduced to a numerical form. It is indeed true, that this ... inclination to employ the doctrine of chances as a sort of auxiliary in the pursuit of a ...

Tópico(s): Probability and Statistical Research

1819 - Royal Society | Philosophical Transactions of the Royal Society of London

Artigo

Michael Faraday,

... and varied refractive and dispersive powers, render glass a most important agent in the hands of the ... is frequently stopped in her progress by them; a fact fully proved by the circumstance that Mr. ... first opticians, has not been able to obtain a disc of flint glass four inches and a half in diameter, fit for a telescope, within the last five years, or a similar disc of five inches in diameter within ... solution of the same practical problem. He was a man of profound science, and had all the ... knowledge they acquired was altogether practical and personal, a matter of minute experience, and not of a ...

Tópico(s): History and Developments in Astronomy

1830 - Royal Society | Philosophical Transactions of the Royal Society of London

Artigo

Michael Faraday,

... the Portable Oil-gas Company, is colourless, of a specific gravity less than that of water; insoluble ... alcohol, ether, oils, &c.; and combustible, burning with a dense flame. It is strikingly distinguished from the ... 250°, or above, for ebullition. By repeated distillations a series of products were obtained from the most ... 200°. On subjecting these, after numerous rectifications, to a low temperature, it was found that some of them concreted into a crystalline mass, and ultimately a substance was obtained ...

Tópico(s): Spacecraft and Cryogenic Technologies

1833 - Royal Society | Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London

Primary Document Acesso aberto

Williamson, Peter,

"Together with a description of the most convenient roads for the British forces to invade Canada in three divisions and make themselves masters of it ...

0000 - Gale Group | Sabin

Artigo

Peter Mark Roget,

... deception which Dr. Roget describes, takes place when a carriage-wheel, rolling along the ground, is viewed through the intervals of a series of vertical bars, such as those of a palisade, or of a Venetian window-blind. In these circumstances, all the ... their position recedes from the vertical, and being a maximum for the horizontal spokes. The convexity of ... to Dr. Roget the proper mode of obtaining a clue to their explanation. It results from his experiments, that a certain degree of velocity in the wheel is ...

Tópico(s): Historical Geography and Cartography

1833 - Royal Society | Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London

Artigo

... Mr. Tulley’s compound achromatic microscopes, consisting of a combination of object-glasses of short focus and ... attention; and as it is often erroneously estimated, a method is pointed out of ascertaining it with ... for every practical purpose. He then enters into a detailed description of the several parts of an ... rapidly moving the objects, and bringing into view a succession of them, while the light remains the ... great stress is laid on the importance of a skilful management of the light. In stating the ...

Tópico(s): History and Developments in Astronomy

1833 - Royal Society | Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London