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vations and reckonings, be within three or four miles of Cape Race." A comparison of these two remarks, under the circumstances in which we were placed at the moment, brought my mind to the conclusion that it is greatly to be wished that the means should be discovered of finding the ship's place more accurately, or that navigators would give Cape Race a little wider berth. Still, I do not remember that one of the steam-packets between England and America was ever lost upon that formidable point.

"We must," said he, "by our last obser- | superable, and which to the same extent has existed in no other science-namely, that all the leading phenomena are in their appearance delusive. It is indeed true that in all sciences superficial observation can only lead, except by chance, to superficial knowledge; but I know of no branch in which, to the same degree as in astronomy, the great leading phenomena are the reverse of true, while they yet appeal so strongly to the senses that sagacious philosophers in antiquity who could foretell eclipses and who discovered the precession of the equinoxes still believed that the earth was at rest in the centre of the universe, and that all the hosts of heaven performed a daily revolution about it as a centre.

It appears to me by no means unlikely that with the improvement of instrumental power, and of the means of ascertaining the ship's time with exactness, as great an advance beyond the present state of art and science in finding a ship's place at sea may take place as was effected by the invention of the reflecting quadrant, the calculation of lunar tables and the improved construction of chronometers. In the wonderful versatility of the human mind, the improvement, when it takes place, will very probably be made by paths where it is least expected.

Whatever advances may be made in astronomical science, theoretical or applied, I am strongly inclined to think that they will be made in connection with an increased command of instrumental power. The natural order in which the human mind proceeds in the acquisition of astronomical knowledge is minute and accurate observation of the phenomena of the heavens, the skilful discussion and analysis of these observations and sound philosophy in generalizing the results. In pursuing this course, however, a difficulty presented itself which for ages proved in

It usually happens in scientific progress that when a great fact is at length discovered it approves itself at once to all competent judges. It furnishes a solution to so many problems and harmonizes with so many other facts that all the other data as it were crystallize at once about it. In modern times we have often witnessed such an impatience, so to say, of great truths to be discovered that it has frequently happened that they have been found out simultaneously by more than one individual. A disputed question of priority is an event of very common very common occurrence. Not so with the true theory of the heavSo complete is the deception practised on the senses that it failed more than once to yield to the announcement of the truth, and it was only when the visual organs were armed with an almost preternatural instrumental power that the great fact found admission to the genera! mind.

ens.

It is supposed that in the very infancy of science Pythagoras or his disciples explained the apparent motion of the heavenly bodies about the earth by the diurnal revolution of the earth on its axis. But this theory, though bearing so deeply impressed upon it the great seal of truth, simplicity, was in such glaring contrast with the evidence of the senses that it failed of acceptance in antiquity or the Middle Ages. It found no favor with minds like those of Aristotle, Archimedes, Hipparchus, Ptolemy, or any of the acute and learned Arabian or mediæval astronomers. All their ingenuity and all their mathematical skill were exhausted in the development of a wonderfully complicated and ingenious but erroneous theory. The great master-truth, rejected for its simplicity, lay disregarded at their feet.

At the second dawn of science the great fact again beamed into the mind of Copernicus. Now, at least, in that glorious age which witnessed the invention of printing, the great mechanical engine of intellectual progress, and the discovery of America, we may expect that this long-hidden revelation, a second time proclaimed, will command the assent of mankind. But the sensible phenomena were still too strong for the theory; the glorious delusion of the rising and the setting sun could not be overcome. Tycho de Brahe furnished his observatory with instruments superior in number and quality to all that had been collected before, but the great instrument of discovery which, by augmenting the optic power of the eye, enables it to penetrate beyond the apparent phenomena and to discern the true constitution of the heavenly bodies was wanting at Uranienburg. The observations of Tycho, as dis

cussed by Keppler, conducted that most fervid, powerful and sagacious mind to the discovery of some of the most important laws of the celestial motions, but it was not till Galileo, at Florence, had pointed his telescope to the sky that the Copernican system could be said to be firmly established in the scientific world.*

On this great name, my friends, assembled as we are to dedicate a temple to instrumental astronomy, we may well pause for a moment.

There is much in every way in the city of Florence to excite the curiosity, to kindle the imagination and to gratify the taste. Sheltered on the north by the vine-clad hills of Fiesole, whose Cyclopean walls carry back the antiquary to ages before the Roman, before the Etruscan, power, the flowery city (Fiorenza) covers the sunny banks of the Arno with its stately palaces. Dark and frowning piles of medieval structure; a majestic dome the prototype of St. Peter's; basilicas which enshrine the ashes of some of the mightiest of the dead; the stone where Dante stood to gaze on the campanile; the house of Michael Angelo, still occupied by a descendant of his lineage and name, his hammer, his chisel, his dividers, his manuscript poems, all as if he had left them but yesterday; airy bridges. which seem not so much to rest on the earth as to hover over the waters they span; the loveliest creations of ancient art, rescued from the grave of ages again to "enchant the world"-the breathing marbles of Michael Angelo, the glowing can

It is another interesting coincidence of events in the year 1609 that Keppler's works De Motu Martis and Astronomia Nova, in which his two first laws are propounded, appeared in this year. I am indebted for this suggestion to Dr. B. A Gould.

vas of Raphael and Titian; museums filled with medals and coins of every age from Cyrus the Younger, and gems and amulets and vases from the sepulchres of Egyptian Pharaohs coeval with Joseph and Etruscan Lucumons that swayed Italy before the Romans; libraries stored with the choicest texts, of ancient literature; gardens of rose and orange and pomegranate and myrtle; the very air you breathe languid with music and perfume, such is Florence. But But among all its fascinations addressed to the sense, the memory and the heart there was none to which I more frequently gave a meditative hour during a year's residence than to the spot where Galileo Galilei sleeps beneath the marble floor of Santa Croce, no building on which I gazed with greater reverence than I did upon the modest mansion at Arcetri, villa at once and prison, in which that venerable, sage passed the sad closing years of his life, of his life, the beloved daughter on whom he had depended to smooth his passage to the grave laid there before him, the eyes with which he had discovered worlds before unknown quenched in blindness:

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teenth century. Of all the wonders of ancient and modern art-statues and paintings, and jewels and manuscripts, the admiration and the delight of ages-there was nothing which I beheld with more affectionate awe than that poor rough tube a few feet in length, the work of his own hands-that very "optic glass" through which the “Tuscan artist” viewed the moon.

At evening from the top of Fesolé
Or in Valdarno, to descry new lands,
Rivers or mountains in her spotty globe;'

that poor little spyglass-for it is scarcely more-through which human eye first distinctly beheld the surface of the moon, first discovered the phases of Venus, the satellites of Jupiter and the seeming handles of Saturn, first penetrated the dusky depths of the heavens, first pierced the clouds of visual error which from the creation of the world involved the system of the universe.

There are occasions in life in which a great mind lives years of rapt enjoyment in a moment. I can fancy the emotions of Galileo when, first raising the newly-constructed telescope to the heavens, he saw fulfilled the grand prophecy of Copernicus and beheld the planet Venus crescent like the moon. It was such another moment as that when the immortal printers of Mentz and Strasburg received the first copy of the Bible into their hands, the work of their divine art; like that when Columbus, through the gray dawn of the 12th of October, 1492-Copernicus, at the age of eighteen, was then a student at Cracow-beheld the shores of San Salvador; like that when the law of gravitation first revealed itself to the intellect of Newton; like that when Franklin saw by the stiffening fibres

of the hempen cord of his kite that he held the lightning in his grasp; like that when Leverrier received back from Berlin the tidings that the planet predicted by him was found.

Yes, noble Galileo, thou art right: E pur si muove―"It does move." Bigots may make thee recant it, but it moves, nevertheless. Yes, the earth moves, and the planets move, and the mighty waters move, and the great sweeping tides of air move, and the empires of men move, and the world of thought moves, ever onward and upward to higher facts and bolder theories. They may seal thy lips, but they can no more stop the progress of the great truth propounded by Copernicus and demonstrated by thee than they can stop the revolving earth.

Close now, venerable sage, that sightless, tearful eye: it has seen what man never before saw; it has seen enough. Hang up that poor little spyglass: it has done its work. Not Herschel nor Rosse has comparatively done more. Franciscans and Dominicans deride thy discoveries now, but the time will come when from two hundred observatories in Europe and America the glorious artillery of science shall nightly assault the skies; but they shall gain no conquests in those glittering fields before which thine shall be forgotten. Rest in peace, great Columbus of the heavens, like him scorned, persecuted, broken-hearted; in other ages, in distant hemispheres, when the votaries of science with solemn acts of consecration shall dedicate their stately edifices to the cause of knowledge and truth, thy name shall be mentioned with honor.

It is not my intention, in dwelling with such emphasis upon the invention of the

telescope, to ascribe undue importance. in promoting the advancement of science, to the increase of instrumental power. Too much, indeed, cannot be said of the service rendered by its first application in confirming and bringing into general repute the Copernican system, but for a considerable time little more was effected by the wondrous instrument than the gratification of curiosity and taste by the inspection of the planetary phases and the addition of the rings and satellites of Saturn to the solar family. Newton, prematurely despairing of any further improvement in the refracting telescope, applied the principle of reflection, and the nicer observations now made no doubt hastened the maturity of his great discovery of the law of gravitation; but that discovery was the work of his transcendent genius and consummate skill.

With Bradley, in 1741, a new period coinmenced in instrumental astronomy-not so much of discovery as of measurement. The superior accuracy and minuteness with which the motions and distances of the heavenly bodies were now observed resulted in the accumulation of a mass of new materials both for tabular comparison and theoretical speculation. These materials formed the enlarged basis of astronomical science between Newton and Sir William Herschel. His gigantic reflectors introduced the astronomer to regions of space before unvisited, extended beyond all previous conception the range of the observed phenomena, and with it proportionably enlarged the range of constructive theory. The discovery of a new primary planet and its attendant satellites was but the first step of his progress into the labyrinth of the heavens. Contemporaneously

with his observations, the French astronomers, and especially La Place, with a geometrical skill scarcely, if at all, inferior to that of its great author, resumed the whole system of Newton and brought every phenomenon observed since his time within its laws. Difficulties of fact with which he struggled in vain gave way to more accurate observations, and problems that defied the power of his analysis of his analysis yielded to the modern improvements of the calculus.

But there is no ultima Thule in the progress of science. With the recent augmentations of telescopic power, the details of the nebular theory, proposed by Sir W. Herschel with such courage and ingenuity, have been drawn in question. Many-most-of those milky patches in which he beheld what he regarded as cosmical matter, as yet in an unformed state, the rudimental material of worlds not yet condensed, have been resolved into stars as bright and distinct as any in the firmament. I well recall the glow of satisfaction with which, on the 22d of September, 1847-being then connected with the University at Cambridge-I received a letter from the venerable director of the observatory there beginning with these memorable words: "You will rejoice with me that the great nebula in Orion has yielded to the powers of our incomparable telescope.

It should be borne in mind that this nebula and that of Andromeda [which has been also resolved at Cambridge] are the last strongholds of the nebular theory."

But if some of the adventurous speculations built by Sir William Herschel on the bewildering revelations of his telescope have been since questioned, the vast progress which has been made in sidereal astronomy-to which, as I

understand, the Dudley Observatory will be particularly devoted-the discovery of the parallax of the fixed stars, the investigation of the interior relations of binary and triple systems of stars, the theories for the explanation of the extraordinary, not to say fantastic, shapes discerned in some of the nebulous systems-whirls and spirals radiating through spaces as vast as the orbit of Neptune-the glimpses at systems beyond that to which our sun belongs,—these are all splendid results which may fairly be attributed to the school of Herschel, and will for ever ensure no secondary place to that name in the annals of science.

In the remarks which I have hitherto made I have had mainly in view the direct connection of astronomical science with the uses of life and the service of man. But a generous philosophy contemplates the subject in higher relations. It is a remark as old at least as Plato, and is repeated from him more than once by Cicero, that all the liberal arts have a common bond and relationship. The different sciences contemplate as their immediate object the different departments of animate and inanimate nature, but this great system itself is but one. Its various parts are so interwoven with each other that the most extraordinary relations and unexpected analogies are constantly presenting themselves, and arts and sciences seemingly the least connected render to each other the most effective assistance.

The history of electricity, galvanism and magnetism furnishes the most striking illustration of this remark. Commencing with the meteorological phenomena of our own atmosphere and terminating with the observation of the remotest heavens, it may

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