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well be adduced on an occasion like the present. Franklin demonstrated the identity of lightning and the electric fluid. This discovery gave a great impulse to electrical research with little else in view but the means of protection from the thundercloud. A purely accidental circumstance led the physician Galvani, at Bologna, to trace the mysterious element under conditions entirely novel, both of development and application. In this new form it became in the hands of Davy the instrument of the most extraordinary chemical operations, and earths and alkalis, touched by the creative wire, started up into metals that float on water and kindle in the air. At a later period the closest affinities are observed between electricity and magnetism on the one hand, while on the other the relations of polarity are detected between acids and alkalis. Plating and gilding henceforth become electrical processes. In the last applications of the same subtle medium it has become the messenger of intelligence across the land and beneath the sea, and is now employed by the astronomer to ascertain the difference of longitudes, to transfer the beats of the clock from one station to another, and to record the moment of his observations with automatic accuracy. How large a share has been borne by America in these magnificent discoveries and applications among the most brilliant achievements of modern science will sufficiently appear from the repetition of the names of Franklin, Henry, Morse, Walker, Mitchel, Locke and Bond.

It has sometimes happened, whether from the harmonious relations to each other of the different departments of science or from rare felicity of individual genius, that the most

extraordinary intellectual versatility has been manifested by the same person. Although Newton's transcendent talent did not blaze out in childhood, yet as a boy he discovered great aptitude for mechanical contrivance. His water-clock, self-moving vehicle and mill were the wonder of the village-the latter propelled by a living mouse. Sir David Brewster represents the accounts as differing whether the mouse was made to advance "by a string attached to its tail" or by "its unavailing attempts to reach a portion of corn placed above the wheel." It seems more reasonable to conclude that the youthful discoverer of the law of gravitation intended, by the combination of these opposite attractions, to produce a balanced movement. It is consoling to the average mediocrity of the race to perceive in these sportive essays that the mind of Newton passed through the stage of boyhood. But, emerging from boyhood, what a bound it made as from earth to heaven! Soon after commencing Bachelor of Arts, at the age of twenty-four, he untwisted the golden and silver threads of the solar spectrum, simultaneously or soon after conceived the method of fluxions, and arrived at the elemental idea of universal gravity before he had passed to his Master's degree. Master of Arts, indeed! That degree, if no other, was well bestowed. Universities are unjustly accused of fixing science in stereotype. That diploma is enough of itself to redeem the honors of academical parchment from centuries of learned dulness and scholastic dogmatism.

But the great object of all knowledge is to enlarge and purify the soul, to fill the mind with noble contemplations and to furnish a refined pleasure. Considering this as

the ultimate end of science, no branch of it can surely claim precedence of astronomy. No other science furnishes such a palpable embodiment of the abstractions which lie at the foundation of our intellectual system— the great ideas of time, and space, and extension, and magnitude, and number, and motion, and power. How grand the conception of the ages on ages required for several of the secular equations of the solar system! of distances from which the light of a fixed star would not reach us in twenty millions of years of magnitudes compared with which the earth is but a football! of starry hostssuns like our own-numberless as the sands on the shore of worlds and systems shooting through the infinite spaces with a velocity compared with which the cannon-ball is a way-worn, heavy-paced traveller!

Much, however, as we are indebted to our observatories for elevating our conceptions of the heavenly bodies, they present, even to the unaided sight, scenes of glory which words are too feeble to describe. I had occasion a few weeks since to take the early train from Providence to Boston, and for this purpose rose at two o'clock in the morning. Everything around was wrapped in darkness and hushed in silence broken only by what seemed at that hour the unearthly clank and rush of the train. It was a mild, serene midsummer's night. The sky was without a cloud; the winds were whist. The moon, then in the last quarter, had just risen, and the stars shone with a spectral lustre but little affected by her presence. Jupiter, two hours high, was the herald of the day; the Pleiades, just above the horizon, shed their sweet influence in the east; Lyra sparkled near sparkled near the zenith; Andro:neda veiled her newly

discovered glories from the naked eye in the south; the steady pointers, far beneath the pole, looked meekly up from the depths of the north to their sovereign.

Such was the glorious spectacle as I entered the train. As we proceeded the timid approach of twilight became more perceptible; the intense blue of the sky began to soften; the smaller stars, like little children, went first to rest; the sister-beams of the Pleiades soon melted together; but the bright constellations of the west and north remained unchanged. Steadily the wondrous transfiguration went on. Hands of angels, hidden from mortal eyes, shifted the scenery of the heavens; the glories of night dissolved into the glories of the dawn. The blue sky now turned more softly gray; the great watch-stars shut up their holy eyes; the east began to kindle. Faint streaks of purple soon blushed along the sky; the whole celestial concave was filled with the inflowing tides of the morning light, which came pouring down from above in one great ocean of radiance, till at length, as we reached the blue hills, a flash of purple fire blazed out from above the horizon and turned the dewy teardrops of flower and leaf into rubies and diamonds. In a few seconds the everlasting gates of the morning were thrown wide open, and the lord of day, arrayed in glories too severe for the gaze of man, began his state.

I do not wonder at the superstition of the ancient Magians who in the morning of the world went up to the hilltops of Central Asia and, ignorant of the true God, adored the most glorious work of his hand; but I am filled with amazement when I am told that in this enlightened age and in the heart of

the Christian world there are persons who can witness this daily manifestation of the power and wisdom of the Creator and yet say in their hearts, "There is no God."

Numerous as are the heavenly bodies visible to the naked eye, and glorious as are their manifestations, it is probable that in our own system there are great numbers as yet undiscovered. Just two hundred years ago this year Huygens announced the discovery of one satellite of Saturn, and expressed the opinion that the six planets and six satellites then known, and making up the perfect number of twelve, composed the whole of our planetary system. In 1729 an astronomical writer came to the conclusion that there might be other bodies in our system, but that the limit of telescopic power had been reached and no further discoveries were likely to be made. The orbit of one comet only had been definitely calculated. Since that time the power of the telescope has been indefinitely increased; two primary planets of the first class, ten satellites and forty-three small planets (August, 1856), revolving between Mars and Jupiter, have been discovered; the orbits of six or seven hundred comets, some of brief period, have been ascertained; and it has been computed that hundreds of thousands of these mysterious bodies wander through our system. There is no reason to think that all the primary planets which revolve about the sun have been discovered. An indefinité increase in the number of asteroids may be anticipated; while, outside of Neptune, between our sun and the nearest fixed star, supposing the attraction of the sun to prevail through half the distance, there is room for ten more primary planets, succeeding each other at dis

tances increasing in a geometrical ratio. The first of these will unquestionably be discovered as soon as the perturbations of Neptune shall have been accurately observed, and with maps of the heavens on which the smallest telescopic stars are laid down any one of them may be discovered much sooner.

But it is when we turn our observation and our thoughts from our own system to the systems which lie beyond it in the heavenly spaces that we approach a more adequate conception of the vastness of creation. All analogy teaches us that the sun which gives light to us is but one of those countless stellar fires which deck the firmament, and that every glittering star in that shining host is the centre of a system as vast and as full of subordinate luminaries as our own. Of these suns-centres of planetary systems-thousands are visible to the naked eye, millions are discovered by the telescope. Sir John Herschel, in the account of his operations at the Cape of Good Hope, calculates that about five and a half millions of stars are visible enough to be distinctly counted in a twenty-foot reflector in both hemispherés. He adds, "That the actual number is much greater there can be little doubt." His illustrious father estimated on one occasion. one hundred and twenty-five thousand stars passed through the field of his forty-foot reflector in a quarter of an hour. This would give twelve million for the entire circuit of the heavens in a single telescopic zone; and this estimate was made under the assumption that the nebulae were masses of luminous matter not yet condensed into suns.

These stupendous calculations, however, form but the first column of the inventory of the universe. Faint white specks are

visible even to the naked eye of a practised observer in different parts of the heavens. Under high magnifying powers several thousands of such spots are visible-no longer. however, faint white specks, but many of them resolved by powerful telescopes into vast aggregations of stars, each of which may with propriety be compared with the Milky Way of our system. Many of these nebulæ, however, resisted the power of Sir William Herschel's great reflector, and were, accordingly, still regarded by him as masses of unformed luminous matter. This, till a few years since, was perhaps the prevailing opinion, and the nebular theory filled a large space in modern astronomical science. But with the increase of instrumental power, especially under the mighty grasp of Lord Rosse's gigantic reflector and the great refractors at Pulkova and Cambridge, the most irresolvable of these nebulæ have given way; and the better opinion now is that every one of them is a galaxy like our own Milky Way, composed of millions In other words, we are brought to the bewildering conclusion that thousands of these misty specks, the greater part of them too faint to be seen by the naked eye, are, not each a universe like our solar system, but each a "swarm" of universes of unappreciable magnitude. The mind sinks overpowered by the contemplation. We repeat the words, but they no longer convey distinct ideas to the understanding.

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only prevent its being more apparent. The great improvement which has taken place in instruments of measurement within the last generation has not only established the existence of this motion, but has pointed to the region in the starry vault around which our whole solar and stellar system, with its myrind of attendant planetary worlds, appears to be performing a mighty revolution. If, then, we assume that outside of the system to which we belong, and in which our sun is but a star like Aldebaran or Sirius, the different nebula of which we have spoken, thousands of which spot the heavens, constitute each a distinct family of universes, we must, following the guide of analogy, attribute to each of them also, beyond all the revolutions of their individual attendant planetary systems, a great revolution comprehending the whole; while the same course of analogical reasoning would lead us still farther onward, and in the last analysis require us to assume a transcendental connection between all these mighty systems-a universe of universes, circling round in the infinity of space and preserving its equilibrium by the same laws of mutual attraction which bind the lower worlds together.

It may be thought that conceptions like these are calculated rather to depress than to elevate us in the scale of being-that, banished as he is by these contemplations to a corner of creation and there reduced to an atom, man sinks to nothingness in this infinity of worlds. But a second thought corrects the impression. These vast contemplations are well calculated to inspire awe, but not abasement. Mind and matter are incommensurable. An immortal soul, even while clothed in "this muddy vesture of de

cay," is in the eye of God and reason a purer essence than the brightest sun that lights the depths of heaven. The organized human eye, instinct with life and spirit, which, gazing through the telescope, travels up to the cloudy speck in the handle of Orion's sword and bids it blaze forth into a galaxy as vast as ours, stands higher in the order of being than all that host of luminaries. The intellect of Newton, which discovered the law that holds the revolving worlds together, is a nobler work of God than a universe of universes of unthinking

matter.

If, still treading the loftiest paths of analogy, we adopt the supposition-to me, I own, the grateful supposition-that the countless planetary worlds which attend these countless suns are the abodes of rational beings like men, instead of bringing back from this exalted conception a feeling of insignificance, as if the individuals of our race were but poor atoms in the infinity of being, I regard it, on the contrary, as a glory of our human nature that it belongs to a family, which no man can number, of rational natures like itself. In the order of being they may stand beneath us or they may stand above us; he may well be content with his place who is made "a little lower than the angels." Finally, my friends, I believe there is no contemplation better adapted to awaken devout ideas than that of the heavenly bodies -no branch of natural science which bears clearer testimony to the power and wisdom of God than that to which you this day consecrate a temple. The heart of the ancient world, with all the prevailing ignorance of the true nature and motions of the heavenly orbs, was religiously impressed by their sur

vey. There is a passage in one of those admirable philosophical treatises of Cicero, composed in the decline of life as a solace under domestic bereavement and patriotic concern at the impending convulsions of the state, in which, quoting from some lost work of Aristotle, he treats the topic in a manner which almost puts to shame the teachings of Christian wisdom:

"Nobly does Aristotle observe that if there were beings who had always lived under ground in convenient-nay, magnificent--dwellings adorned with statues and pictures, and everything which belongs to prosperous life, but who had never come above ground-who had heard, however, by fame and report, of the being and power of the gods-if at a certain time, the portals of the earth being thrown open, they had been able to emerge from those hidden abodes to the regions inhabited by us; when suddenly they had seen the earth, the seas and the sky, had perceived the vastness of the clouds and the force of the winds, had contemplated the sun, his magnitude and his beauty, and still more his effectual power, that it is he who makes the day by the diffusion of his light through the whole sky; and when night had darkened the earth should then behold the whole heavens studded and adorned with stars, and the various lights of the waxing and waning moon, the risings and the settings of all those heavenly bodies, and their courses fixed and immutable in all eternity, when, I say, they should see these things, truly they would believe that there are gods, and that these so great things are their works."

There is much by day to engage the attention of the observatory-the sun, his apparent motions, his dimensions, the spots on

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