CHAPTER XXXIII.

MODERN ASTRONOMY.

Still, however, the world was not convinced of the truth of the Copernican system. One man here or there saw and acknowledged its reality. The mass of mankind continued firmly to believe that they dwelt at the universe center, and utterly to scout the idea of a moving earth. Indeed, it may be very much doubted whether, not merely the mass of mankind, but even the most civilized and cultivated portion of that mass, had as yet, to any wide extent, heard a whisper of the new theories. Knowledge, in those days, traveled from place to place with exceeding deliberation.

Another great man arose, contemporary with Kepler--a man whose story seizes more strongly upon our imagination than that of the severe and successful studies of Kepler. From an ordinary worldly point of view, Kepler would hardly be looked upon as altogether a successful man. He was poor, and in sickly health. His chief book was promptly prohibited by Rome--then a power in the whole reading world of Europe to an extent which can hardly be realized in these days of freedom. Kepler’s book was placed in the forbidden category, side by side with the dying publication of Copernicus. This checked all hope of literary gains, and life with Kepler was one long struggle. But if he could have looked ahead two or three hundred years; if he could have foreseen the time when not a few wise men of science alone, but all the civilized world, including the very Church which condemned him, should meekly have accepted and indorsed his discoveries,--then he would have been able to gauge the measure of his own real success.

Moreover, with all his troubles, Kepler was so happy as to escape absolute persecution. He lived in a country which knew something of liberty as an ideal; he was left to write and work freely; and, at least, no public recantation of what he held to be truth was forced from him.

Galileo’s was a sadder tale. A Florentine of noble birth, he turned his attention early to science as the needle turns to the north, and before the age of twenty-seven he already occupied a foremost position as mathematical lecturer at Pisa. There it was that he direfully offended the philosophers of the day by proving Aristotle to be in the wrong. For Aristotle was the great master of the schoolmen. His philosophy and theories were accepted as final, and whatsoever could not be proved in accordance with them was regarded as untrue. Aristotle had declared that if two weights--the one being ten times as heavy as the other--were dropped together from a height, the heavier weight would reach the ground ten times as quickly as the lighter.

Everybody believed this, and nobody had ever thought of putting it to the test of actual trial. Aristotle had said so, and Aristotle was indorsed as a whole by all the schools of Europe; and what more could possibly be wanted by any reasonable human being? But Galileo was not so easily satisfied. He looked into the matter independently, bent upon finding out, not what Aristotle had thought or what the Church might support, but simply what actually _was_.

[Illustration: PROMINENT ASTRONOMERS OF THE NINETEENTH CENTURY.]

Then, in view of many observers, called together for the occasion, he dropped, at the same instant, from the top of the leaning tower of Pisa, a shot weighing one pound and another shot weighing a hundred pounds. And, behold! both reached the ground simultaneously. There was not a fraction of difference between the two. To prove Aristotle wrong was to prove everybody wrong, the authorities of the Church included. Men calmly declined to believe their own eyes, and Galileo was in very evil odor.

From falling bodies he went on to subjects of yet wider interest to people in general. He read about and eagerly embraced the Copernican system. Not only did he accept it himself, but he vigorously set to work to teach and convince others also. This, as might only be expected, aroused vehement opposition. But Galileo was still in the heyday of his powers, and he was not to be easily silenced. In those days he could afford to press onward in the teeth of resistance, and to laugh at men who would not listen.

When at Venice, a report reached him of a certain optician in Holland who had happened to hit upon a curious “combination of lenses,” through which objects afar off could be actually seen as if they were near. Galileo promptly seized upon the notion, and within twenty-four hours he had rigged up a small, rough telescope out of an old organ-pipe and two spectacle-glasses.

Thus the first telescope was made--a very elementary affair, formed of two lenses, convex and concave, and capable of magnifying some three times--a mere child’s toy compared with telescopes of the present day, but of exceeding value and interest, because it was the very first; because in all the history of the world no telescope had ever been manufactured before.

This earliest effort was speedily improved upon. The next trial produced a tube which could magnify seven or eight times; and in a little while, Galileo had a telescope magnifying as much as thirty-two times. Even thirty-two times does not sound very startling to us; but in those days the revelations of such an instrument came upon men like a thunderclap.

Through it could be seen clearly the broken nature of the moon’s surface--the craters, the shadows, the mountains. Through it could be seen the phases of Venus, which no man had ever yet detected, but which Copernicus had declared must certainly exist, if indeed his system were a reality. Through it could be seen four of the moons of Jupiter, and their ceaseless journeyings. Through it could be seen spots upon the face of the sun, the movements of which showed the rotation of the sun upon his axis. Through it could be seen the very curious shape of Saturn, caused by his rings, though a much stronger power was needed to separate the rings from the body of the planet.

Of all these discoveries, and many others also made by Galileo, none seemed worse to the bigoted schoolmen of his day than the preposterous notion of black spots upon the sun’s face.

Rather curiously, no human being seems ever before then to have noticed such spots, though often they are quite large enough to be detected by the naked eye. A general belief had been held that the sun was and must be perfect--an absolutely spotless and unblemished being, the purest symbol of celestial incorruptibility--and the said discovery went right in the teeth of deductions drawn from, and lessons founded upon, this belief. Therefore the schoolmen held out and determinedly resisted, and would have nought to do with Galileo or his telescopes, shutting their eyes to marvels newly revealed.

But Kepler was a true scientist, a man who earnestly pursued truth, and sought to discover it at any hazard. He and Galileo were contemporaries, and they held communication on these subjects. Some of Galileo’s discoveries went quite as much in the teeth of some of Kepler’s most dearly-loved theories as they did in the teeth of the schoolmen’s most dearly-loved doctrines. Yet, none the less, Kepler welcomed them with great delight and eagerness, showing thereby his true greatness of character.

Till after the age of fifty, Galileo was allowed to go on undisturbed, or at least not materially disturbed, by opposition in his career of success--observing, learning, theorizing, calculating, explaining, teaching--a prominent figure indeed. Not only did he take a large share in establishing firmly the Copernican system of astronomy, but some of the principal laws of motion were discovered by him. He first found the uses of a pendulum, and there is strong reason for believing that the first microscope, as well as the first telescope, was from his hands.

But after the age of fifty, reverses came, and one blow succeeded another. Rome had been gradually waking up to the true sense of all that was implied by his discoveries and his teaching, and at length she let loose her thunders--impotent thunders enough, so far as regarded any permanent checking of the progress of truth, but by no means impotent to crush one defenseless victim, the champion of scientific truth in that country and age.

Years of greater or less opposition, amounting often to persecution, were followed by an imperious order commanding him to Rome. There he was examined and severely “questioned,” and recantation was forced from him, worth as much as such forced recantations commonly are worth.

Even then he did not cease from the work that he loved; even in prison he carried it on; even when he might not write, nothing could stop him from thinking. But his health was broken; his liberty was taken away; illness followed illness; his favorite daughter died; his eyesight gradually failed; the last book that he wrote might not for a long while be printed; and at last he passed away, mercifully set free from those who, in an essentially bigoted and intolerant age, were incapable of appreciating his greatness.

They would fain _then_ have denied him even a respectable grave. Now, all the civilized world unites to honor the name of Galileo.