The Works of John Playfair ...: With a Memoir of the Author ...A. Constable & Company, 1822 - 8 من الصفحات |
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accurate Albert Girard algebraic Alhazen analysis ancient angles appears applied areas astronomer axis Bacon Bernoulli calculus cause centre centrifugal force circle colour conclusion considered Copernicus curve deduced degree Descartes direction discovered discoveries distance earth effect employed entirely epicycle equal equation error experiment explained facts fluxions force Galileo genius geometer geometry given gravity heavens Huygens infinitely ingenious inquire instantia instruments invention investigation John Bernoulli Kepler knowledge known laws of Kepler Leibnitz light mathematical mathematicians matter means measure ment method method of Exhaustions method of fluxions moon motion moving body natural philosophy nature neral Newton objects observed optical orbit phenomena philosopher physical planets principle problem produced proposition Ptolemy quadrature ratio rays reasoning rectilineal refraction remarkable resolved round seemed solution square stars supposed surface telescope theory thing tion treatise true truth Tycho variable quantities velocity vis viva
مقاطع مشهورة
الصفحة 163 - Rather admire; or if they list to try Conjecture, he his fabric of the Heavens Hath left to their disputes, perhaps to move His laughter at their quaint opinions wide Hereafter, when they come to model Heaven And calculate the stars, how they will wield The mighty frame; how build, unbuild, contrive To save appearances; how gird the sphere With centric and eccentric scribbled o'er, Cycle and epicycle, orb in orb...
الصفحة 431 - That gravity should be innate, inherent, and essential to matter, so that one body may act upon another at a distance through a vacuum, without the mediation of anything else, by and through which their action and force may be conveyed from one to another, is to me so great an absurdity that I believe no man who has in philosophical matters a competent faculty of thinking can ever fall into it.
الصفحة 332 - Law of Continuity — according to which nothing passes from one state to another without passing through all the intermediate states.
الصفحة 73 - As things are at present conducted," he adds, " a sudden transition is made from sensible objects and particular facts to general propositions, which are accounted principles, and round which, as round so many fixed poles, disputation and argument continually revolve. From the propositions thus hastily assumed, all things are derived by a process compendious and precipitate ; ill suited to discovery, but wonderfully accommodated to debate. The way that promises success is the reverse of this. It...
الصفحة 23 - Cycloid afforded a number of problems, well calculated to exercise the proficients in the geometry of indivisibles, or of infinites. It is the curve described by a point in the circumference of a circle, while the circle itself rolls in a straight line along a plane. It is not quite certain when this curve, so remarkable for its curious properties, and for the place which it occupies in the history of geometry, first drew the attention of mathematicians. In the year...
الصفحة 383 - Sarum in proposing me a candidate ; and which, I hope, will be further conferred upon me by my election into the Society ; and if so, I shall endeavour to testify my gratitude, by communicating what my poor and solitary endeavours can effect towards the promoting your philosophical designs.
الصفحة 75 - is not like a plane mirror, which reflects the images of things exactly as they are ; it is like a mirror of an uneven surface, which combines its own figure with the figures of the objects it represents.
الصفحة 431 - It is inconceivable, that inanimate brute matter should, without the mediation of something else, which is not material, operate upon and affect other matter without mutual contact, as it must be, if gravitation, in the sense of Epicurus, be essential and inherent in it.
الصفحة 99 - That the squares of the times of the revolutions of the planets are as the cubes of their mean distances from the sun.
الصفحة 105 - When in any investigation the understanding is placed in equilibria, as it were, between two or more causes, each of which accounts equally well for the appearances, as far as they are known, nothing remains to be done, but to look out for a fact which can be explained by one of these causes and not by the other.