Edward Singleton Holden

“ I think, my Kepler, we will laugh at the extraordinary stupidity of the multitude. What do you say to the leading philosophers of the faculty here, to whom I have offered a thousand times to show my studies, but who. . . have never consented to look at planets, nor Moon, nor telescope? Verily, just as serpents close their ears, so do these men close their eyes to the light of truth. ”

“ From this moment no competent witness could doubt the truth of the Copernican system—Galileo less than any one.
An opportunity unique in the history of the world was presented to Galileo and he utilized it to the full. He went from triumph to triumph. The phases of Venus, the mountains of the moon, the constitution of the Milky Way, the tricorporate figure of Saturn, the solar spots, the moons of Jupiter, were death-blows to the systems of Aristotle and of Ptolemy, and were skilfully utilized to establish the system of Copernicus. ”

“ This is daily done, if possible, on every one of the ships sailing out of New York City, and on the skill of her officers, the goodness of her chronometers, and the accuracy of their rates, depends the safety of her passengers and cargo. To all men of business, then, in their appointments and affairs on shore and in their commercial ventures by sea, the fact that a standard time is easily attainable and perfectly correct is of no slight importance. To travelers, whether by sea or land, it is truly a matter of life and death. ”

“ Sixteen hundred years earlier Lucretius had come near to the same truth: “For whenever bodies fall through water and thin air they must quicken their descents in proportion to their weights, because the body of water and subtle nature of air can not retard everything to an equal degree; on the other hand, empty void can not offer resistance to anything in any direction at any time, but must continually give way; and for this reason all things must be moved and borne along with equal velocity, though of unequal weights, through the unresisting void.” ”

“ If his experiments were to be believed, the words of Aristotle were false. If the philosophy of Aristotle were false in one part it might be false in all. The experiments must therefore be denied, and their author discredited. It is recorded that the experiments were, in fact, denied. The facts of experience were met with argument. Galileo's retorts were bitter and brilliant, his sarcasms searching and unsparing. Before the end of his three years' engagement as professor had expired, he had involved himself in a hopeless wrangle with his colleagues and with Aristotelians throughout Italy. ”

“ THERE is a certain fascination in our scanty knowledge of the elder nations of the earth, which is due quite as much to their chronological position as to the intrinsic interest of their doings and sayings; and it owes not a little of its keenness to the very scantiness of that knowledge.
We are continually told that this is a practical century; that we are utilitarians in the strictest sense; that there is no romantic faculty left to us; that we are apt to scorn all knowledge which has not a direct practical bearing on the daily life and interests of us all. ”

“ The Grand Duke and most of the court were his admiring friends. He had every freedom for research if only he would leave the interpretation of scripture to theological experts. ‘Write freely, but keep outside the sacristy’ his friends advised. Why did he remain in Rome? To convert the Congregation of the Index to Copernicanism? This would have been a triumph for science, and a personal triumph as well. The Roman Curia had absolutely no interest in science as such. They were determined that religion should not suffer. Galileo's brilliant lectures were not conceived in the spirit that convinces. ”

“ On the earth a pendulum stops because of the resistance of the air and the friction at its supports. Remove the air and annul the friction and it will swing forever until some impressed force stops it, so Galileo announced. Kepler was incessantly trying to conceive how a planet could continue to move in its orbit, and was forced to conclude that some inherent energy, perhaps an angel, perpetually acted to keep it moving. Galileo's law announces that if it is once set in motion it will continue to move until some impressed and extraneous force causes it to stop. ”

“ Since the wide ocean of science is difficultly traversed by men of little understanding, and, on the other hand, the intelligent have no occasion for copious instruction, a particle of tuition conveys science to a comprehensive mind, and, having reached it, expands of its own impulse. ”

“ Nature, on the contrary, is inexorable and unchangeable, and cares not whether her hidden causes and modes of working are intelligible to the human understanding or not, and never deviates from her prescribed laws.” It appears to me, therefore, says Galileo, that no effect of nature, which experience places before our eyes, or is the necessary conclusion derived from evidence, should be rendered doubtful by passages of Scripture which contain thousands of words admitting of various interpretations, for every sentence of Scripture is not bound by such rigid laws as is every effect of Nature. ”

“ There is little doubt but that the long and dreary hours spent over the drawing-table were an admirable though tedious preparation for the series of astronomical delineations which have been of so solid a use to science. But, finally, in the lack of real opportunities, architecture ceased to be a profession, and became a business, a means to live simply. ”

“ The lesson of patience which can be learned from the labors of these successors is no mean one. To this patience, supplemented by a skill which usually must be of a high order, we owe the later discoveries of the telescope, such as the finding of the eighth satellite of Saturn (by Bond and Lassell) , and of the two interior moons of Uranus (Lassell, 1847 and 1851) , and of the satellite of Neptune.
There is hardly an object in the whole heavens—planets, of course, excepted—which has been so thoroughly and faithfully studied as the Great Nebula in Orion. ”

“ We require our thoughts to be suggested sometimes by an age of old and quaint habits, of strange people with stranger gods. In our busy life, it is a relief to turn to the Hindoo, who could spare the time "to sit beneath the tree and contemplate his own perfections," or to the Egyptian who evolved pyramids, and obelisks, and avenues of sphinxes, out of his infinite leisure. ”

“ The opinion of most astronomers has been, that personal equation is not purely a physiological phenomenon, but likewise a psychological. The time required for the sound of the clock to reach the observer's brain, and the time required for the light to pass from the image of the star, so as to excite the nerves of vision, are both very small: it is the coördinating power of the brain that works slowly—and absolute personal equation is largely the measure of the time required for the brain to superpose two different sensations, to coördinate impressions derived from different sets of nerves. ”

“ If in the stone, why does it ever come to rest? Aristotle's answer is that ‘a motion is communicated to the air, the successive parts of which urge the stone onward; each portion of the air continues to act for some little time after it has been acted upon, and the motion ceases when it comes to a particle which can not act after it has been acted upon.’ The confusion of this explanation is complete. ”

“ Galileo's discoveries were received with incredulity by the wisest men of Italy. The warm-hearted Kepler (April, 1610) was the first to recognize ‘the divinity of his genius.’ Little by little they made their way as Galileo demonstrated them triumphantly to friends and enemies. Arguments of all sorts were brought against them and against the heliocentric theory which they supported.
Animals, which move, have limbs and muscles; the earth has no limbs and muscles, therefore it does not move. It is angels who make Saturn, Jupiter, the sun, etc., turn round. ”

“ Events in themselves are of small moment; the impression that events produce is the only revelation of the public consciousness. Never before has its generous aversion for intolerance burst forth so strongly as for the sufferings of Galileo. ”

“ Every military engineer who had watched the flight of a projectile was aware that the received notions of mechanics would not explain its motions. No theory of the impact of such projectiles had even been proposed. A whole science was to be created. The doctrine of mechanical equilibrium is statics—and this science was founded by Archimedes. The doctrine of mechanical motion is dynamics—and nothing was done in this science till the time of Galileo. ”

“ Fortunately, this study demanded very few auxiliary pieces of apparatus: the telescope has to be directed upon the sun, its motor-clock keeps it constantly pointed upon the same spot, and the observer has to follow, with infinite diligence and patience, the elusive details which the moments of best vision may allow him to glimpse. ”

“ It was no wonder that young Langley, whose genius lay in quite another direction, should look about him, after his graduation from the school, to see if there were not some practicable way in which he could pursue those mechanical and astronomical studies that already had fascinated him. He had little inclination to enter college, and the openings in astronomy proper were very rare in those years, even rarer than now. Since he was ten years old, he had been reading and studying astronomy, making small telescopes, using these and others, with various success, but always with ardor. ”

“ Were there no such selective absorption, the temperature of the soil in the tropics, under a vertical sun, would probably not rise to that of the freezing-point of mercury. "The temperature of this planet, and with it the existence, not only of the human race but of all organic life on the globe, appears, from the results of the Mount Whitney expedition, to depend far less on the direct solar heat" than on the hitherto neglected quality of selective absorption. ”

“ When they are once familiar, new pleasures are discovered; and not until then do they begin to gain acceptance. Kepler ‘shuddered’ at the very idea of an infinite universe. Even he had not completely shaken off the Ptolemaic conception of a limited world. The authority of the Roman Church had been in theory literally universal, and Copernicus limited its world to one small planet, not so large as Jupiter as Galileo showed a few years later. ”

“ It is true that especial attention has been paid by some astronomers to the smaller stars in this nebula; while some, as Herschel the younger, have evidently bestowed more care upon the grades of light in the nebula itself; but, on the whole, we shall find that the number and faintness of the small stars, seen by any astronomer in any one limited region, are a very fair test of his own assiduity, and of the excellence of his telescope. ”

“ The ideas of Aristotle as to motion and rest were not physical, but metaphysical. An example will illustrate his mode of reasoning which satisfied the scientific world for something like two thousand years. When a stone is thrown from the hand why does it continue to move for a time, and why does it eventually come to rest? Where is the cause of motion—in the hand?—or in the stone? ”

“ The farm-laborer who eats his dinner in the field at the time that shadows cast by the sun point north and south is the victim of his own ignorance, as he sometimes anticipates the noon of watches and clocks by more than a quarter of an hour, and is sometimes equally in retard. ”

“ The heliocentric doctrine has for a century been making its way into the minds of thoughtful men on the general ground of its simplicity and symmetry. Galileo appears to have thought that now, when these original recommendations of the system had been reenforced by his own discoveries and reasonings, it ought to be universally acknowledged as a truth and a reality. And when arguments against the fixity of the sun and the motion of the earth were adduced from scripture, he could not be satisfied without maintaining his favorite opinion to be conformable to scripture as well as to philosophy ”

“ Every particle of matter in the universe attracts every other particle with a force directly as the masses of the two particles, and inversely as the squares of the distance that separates them. With these laws as bases of calculation the question may be answered: What orbit will a planet describe about the sun? The answer is, a conic section, an ellipse for example. Again: What will be the law of the motion of each planet in its ellipse? The answer is: Its radius-vector will sweep over equal areas in equal times. Again: In a system of such planets, how will their orbits be related? ”

“ We can never be sure we have eliminated them so long as the human mind or body is a part of the machine by means of which we are comparing or registering events; and, just so long as mind or body is employed, we can be sure that personal differences will not only exist, but that they will vary from day to day. ”

“ In astronomical observations the senses are trained to a fine delicacy, and old observers acquire a constancy of habit which gives to their work a homogeneousness that is wanting in that of younger men.
We have given a brief account of the early method of estimating the time of a star's transit across a spider-line in the field of the telescope by the method of eye and ear; there is yet another method now in common use, which it is necessary to understand before we pass to the consideration of the means of determining personal equation. ”