Walter William Bryant

“ If the earth should cease to attract its waters to itself all the waters of the sea would he raised and would flow to the body of the moon. The sphere of the attractive virtue which is in the moon extends as far as the earth, and entices up the waters; but as the moon flies rapidly across the zenith, and the waters cannot follow so quickly, a flow of the ocean is occasioned in the torrid zone towards the westward. If the attractive virtue of the moon extends as far as the earth, it follows with greater reason that the attractive virtue of the earth extends as far as the moon and much farther ”

“ It is universally admitted that those phenomena which come under the daily observation of mankind, and which on that account do not possess any salient features on which the imagination can repose, are generally those which are most liable to elude the inquiries of ordinary minds. The principles which Galileo established by his sagacious researches had the effect of elevating mechanical science to the dignity of one of the most important subjects which can concern the attention of mankind. ”

“ He despises "The common herd of prophesiers who describe the operations of the stars as if they were a sort of deities, the lords of heaven and earth, and producing everything at their pleasure. They never trouble themselves to consider what means the stars have of working any effects among us on the earth whilst they remain in the sky and send down nothing to us which is obvious to the senses, except rays of light." ”

“ Galileo then knelt before the Inquisition, read aloud the prescribed form of abjuration, and signed it. This must have been the climax of the moral torture of the last ten months. We may acquit the Inquisition of having inflicted physical torture, and Galileo's actual imprisonment could only have been for the three days, June 21 to 24, and was probably not even in a dungeon. It seems as if a very little harshness of this kind at the beginning of the trial would have been enough to kill the old man, who was already ill, but he would then have escaped practically all the punishment intended. ”

“ When we come to consider his claims to fame, it is necessary to pay due regard to a sense of proportion. It is a commonplace to observe that his astronomical discoveries were bound to be made as, a direct consequence of the invention of the telescope, so that, though he is popularly known almost entirely by them, they cannot be rated very highly in comparison with his achievements in other directions. The science of dynamics may be said to have been started by him, and he came very near to more than one great discovery for which later scientists have, earned undying glory. ”

“ The exigencies of the censorship prevented any of the most powerful arguments being pushed right home, as it was necessary at every critical point to emphasise the formality that the Copernican system was not to be regarded as true but only as a not impossible hypothesis. Some such display might be made by a skilled fencer against a hopelessly inferior opponent, who wears, however, a coat of adamant guaranteed to shatter the blade that touches it, so that no victory is to be allowed, every stroke being obliged to recoil. ”

“ Nothing which consists of corporeal matter is absolutely light, but that is comparatively lighter which is rarer, either by its own nature, or by accidental heat. And it is not to be thought that light bodies are escaping to the surface of the universe while they are carried upwards, or that they are not attracted by the earth. ”

“ The moral bullying to which he was subjected is very, like the physical twisting of a boy's arm, until he admits that his tormentor is a "perfect gentleman," or some such obvious falsehood. So generally has the abjuration been regarded as compulsory perjury on the part of Galileo, that more than a century after his death a story was invented that immediately after his public denial of the earth's motion he muttered "Eppur si muove," but though doubtless he thought something of the kind, it is absolutely certain that the story is false. ”

“ Those which have failed seem to us only fanciful; those which have been more fortunate appear sublime. When in search of that which really existed, he has sometimes found it; when he devoted himself to the pursuit of a chimera, he could not but fail, but even then he unfolded the same qualities, and that obstinate perseverance that must triumph over all difficulties but those which are insurmountable. ”

“ If we wish to form a clear idea of Galileo's services to science, we must not only take account of his great inventions and discoveries, but also of his elegant style, his comprehensive sagacity and fertility of argument, whether on behalf of truth or in the exposure of error. ”

“ It was obvious that the period was not simply proportional to the distance, as the outer planets were all too slow for this, and he concluded "either that the moving intelligences of the planets are weakest in those that are farthest from the sun, or that there is one moving intelligence in the sun, the common centre, forcing them all round, but those most violently which are nearest, and that it languishes in some sort and grows weaker at the most distant, because of the remoteness and the attenuation of the virtue". ”

“ When a plane containing the earth's axis and passing through the centre of the sun also passes through that of the moon or a planet, at the same side of the earth, the moon or planet is in conjunction, or if on opposite sides of the earth, the moon or planet is in opposition. ”

“ Copernicus had required a great deal of faith to support his system in the face of enormous practical difficulties. Galileo's telescope had disposed of some of these difficulties, by showing that the stars are much farther off than the planets and the sun, and that certainly some of the planets do revolve about the sun; Jupiter's moons also showed the possibility that the earth might not be the centre of the system, although it clearly has a moon revolving round it. ”

“ He went carefully into the question of refraction, the importance of which Tycho had been the first astronomer to recognise, though he only applied it at low altitudes, and had not arrived at a true theory or accurate values. Kepler wasted a good deal of time and ingenuity on trial theories. He would invariably start with some hypothesis, and work out the effect. He would then test it by experiment, and when it failed would at once recognise that his hypothesis was a priori bound to fail. He rarely seems to have noticed the fatal objections in time to save himself trouble. ”

“ Of all the writers who have lived in an age which was only emerging from ignorance and barbarism, Galileo has most entirely the tone of true philosophy, and is most free from the contamination of the time in taste, sentiment, and opinion. ”

“ Galileo, having thus acquired some economic security, threw himself with increased ardour into the investigations that he loved, and set to work systematically to test by experiment everything in Aristotle's mechanics. ”

“ There is no doubt that Kepler strongly resented having to depend so much for his income on such methods which he certainly did not consider creditable.
It was probably Galileo whose praise of the new Tables induced the Grand Duke of Tuscany to send Kepler a gold chain soon after their publication, and we may perhaps regard it as a mark of favour from the Emperor Ferdinand that he permitted Kepler to attach himself to the great Wallenstein, now Duke of Friedland, and a firm believer in Astrology. The Duke was a better paymaster than either of the three successive Emperors. ”

“ On the other hand it must not be forgotten that such accidents have a habit of happening only to great men, and that if Kepler loved to give reins to his imagination he was equally impressed with the necessity of scrupulously comparing speculative results with observed facts, and of surrendering without demur the most beloved of his fancies if it was unable to stand this test. ”

“ The sagacity and skill which Galileo displays in resolving the phenomena of motion into their constituent elements, and hence deriving the original principles involved in them, will ever assure to him a distinguished place among those who have extended the domains of science. ”

“ With these figures in his mind, Kepler looked up the greatest optical inequality of Mars, the angle between the straight lines from Mars to the Sun and to the centre of the circle. [1] The secant of this angle was 1⋅00429, so that he noted that an ellipse reduced from the circle in the ratio of 1⋅00429 to 1 would fit the motion of Mars at the mean distance as well as the apses.
It is often said that a coincidence like this only happens to somebody who "deserves his luck," but this simply means that recognition is essential to the coincidence. ”