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and interesting an occurrence, the American Philosophical Society appointed a committee, of which Mr. Rittenhouse was a member, and directed a temporary observatory to be erected near his residence, in Norriton township. Of the part which Mr. Rittenhouse acted in these preparations, and of the high character which he already bore, we may judge by the following extract from a communication made to the society, by Dr. Smith, who was also a member of the astronomical committee. “As Mr. Rittenhouse's dwell. ing (says the Dr.) is about twenty miles northwest of Philadelphia, our other engagements did not permit Mr. Lukens or myself to pay much attention to the necessary preparations; but we knew we had intrusted them to a gentleman on the spot (meaning Mr. Rittenhouse) who had, joined to a complete skill in mechanics, so extensive an astronomical and mathematical knowledge, that the use, management, and even construction of the apparatus were perfectly familiar to him. The laudable pains he had taken in these material articles, will best appear from the work itself, which he hath committed into my hands, with a modest introduction, giving me a liberty with them, which his own accuracy, taste and abilities leave no room to exercise. We are naturally led here,' says an eloquent eulogist of Mr. Rittenhouse,* •to take a view of our philosopher, with his associates, in their preparations to observe a phenomenon, which had never been seen but twice before, by any inhabitant of our earth, which would never be seen again by any person then living, and on which depended very important astronomical consequences. The night before the long expected day was probably passed in a degree of solicitude which precluded sleep. How great must have been their joy when they beheld the morning sun, and “the whole horizon without a cloud,” for such is the description of the day, given by Mr. Rittenhouse, in the report referred to by Dr. Smith. In pensive silence and trembling anxiety, they waited for the predicted moment of observation: it came; and brought with it all that had been wished for and expected by those who saw it. In our philosopher, it excited, in the instant of one of the contacts of the planet with the sun, an emotion of delight so exquisite and powerful, as to induce fainting. This will readily be believed by those, who have known the extent of that pleasure, which attends the discovery or first perception of truth.'

On the ninth of November, of the same year, there was likewise a transit of Mercury over the sun, which was observed at Norriton, by the same committee. A detailed history of these observations, as well as of those also made under the auspices of the American Philosophical Society, at Philadelphia and Cape Henlopen, is contained in the first volume of their Transactions. The celebrated astronomer royal, Dr. Maskelyne, has declared,

* Dr. Benjamin Rush. + In a letter to the Hon. T. Peon, proprietary of the then province of Pennsyl

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that the Pennsylvania observations of the transit were excellent and complete, and did honour to the gentlemen who made them, and to those who had promoted the undertaking.'

The reputation which Mr. Rittenhouse had now so justly acquired, as an astronomer, attracted the attention of the government, and he was employed in several geodesic operations, of great public importance.

In the year 1779, he was appointed, by the legislature of Pennsylvania, one of the commissioners for adjusting a territorial dispute, between that state and Virginia; and the success of this commission is ascribed, in a great degree, to his skill and prudence.

In 1786, he was employed in fixing the northern line, which divides Pennsylvania from New York.

In 1769, he was employed in settling the limits between New Jersey and New York; and, in 1787, he was called upon to assist in fixing a boundary line between the states of Massachusetts and New York

Let us call upon those, who are in the habit of considering the pursuits of the philosopher as barren and useless, to cast their eyes once more over this list of labours; and then say, whether they were not of indispensable practical importance, and whether any thing but science could have accomplished them.

The literary honours, which the grateful votaries of science so gladly confer upon successful genius, were lavished upon Mr. Rittenhouse. In 1768, the degree of master of arts was conferred upon him by the college of Philadelphia. The same degree was also conferred by the college of William and Mary, in Virginia, in 1784. In the year 1789, he received the degree of doctor of laws, from the college of New Jersey. He was elected a member of the American Academy of Arts and Sciences, at Boston, in 1782, and of the Royal Society of London, in 1795.

In the year 1791, he was chosen the successor of Dr. Franklin, in the presidency of the American Philosophical Society, the most elevated station that science can confer in our country. The connexion of Dr. Rittenhouse with this society, was certainly important both to him and to them. All his philosophical communications were made through the medium of their transactions; and the following list of his papers, printed in the three first volumes, will show his zeal for science, and the fertility of his genius.

Observations of the comet which appeared in June and July 1770, with the elements of its motion, and trajectory of its path; in a letter to Dr. William Smith.

An easy method of deducing the true time of the Sun's passing the meridian, by means of a clock, from a comparison of four equal altitudes, observed on two succeeding days, without the help of the equation tables; communicated by Dr. Wm. Smith.

An explanation of an optical deception; namely, that the surfaces of bodies, viewed through the double microscope, sometimes appear

to be reversed, that is, those parts which are elevated seem depressed, and the contrary.

An account of a remarkable meteor, observed at Philadelphia, on the 31st of October, 1775; with some conjectures relative to the theory of meteors; in answer to a letter from John Page, Esq., giving an account of the same meteor, seen in many

distant places in Virginia.

Conjectures, corroborated by experiments, relative to a new theory of magnetism; in a letter to John Page, Esq., of Virginia.

A new method of placing a meridian mark for a transit instrument, within a few feet of the observatory, so as to have all the advantages of one placed at a great distance; in a letter to the Rev. Dr. John Ewing.

Observations on a comet discovered in the month of January, 1784.

An explanation of a curious optical phenomenon; namely, if a candle or other luminous body be viewed though a silk umbrella, handkerchief or the like, the luminous body will appear to be doubled; in a letter to Francis Hopkinson, Esq.

A series of observations, made at sundry times, in the years 1784, 85, and 86, on the new planet, or Georgium Sidus, also an observation of the transit of Mercury over the sun's disk, on the twelfth of November, 1782.

An account of three houses in Philadelphia, struck with lightning, on the seventh of June, 1789.

An account of the effects of a stroke of lightning upon a house furnished with two metallic conductors, on the seventeenth of August, 1789; in a letter to Mr. Robert Patterson.

Astronomical observations made at Philadelphia; containing an account of the eclipse of the moon, on the second of November, 1789.

An account of the transit of Mercury over the Sun's disk on the fifth of November, 1789.

An account of the eclipse of the Sun, on the sixth of November, 1790, with an account of corresponding observations made at the university of William and Mary, in Virginia, by Dr. J. Madison, and at Washington college in Maryland, by the Rev. Dr. Smith.

Short and elegant theorems for finding the sum of the several powers of the sines, either to a radius of unity, or any other; in a letter to Mr. Robert Patterson.

An account of a comet discovered in the month of January, 1793; in a letter to Mr. Robert Patterson.

A method of determining the true plane of a planet in an elliptical form, by converging series, directly from the mean anomaly.

A new and easy method of calculating logarithms; in a letter to Mr. Robert Patterson.

A description of an improvement on pendulum-clocks; by which the error arising from the different density or resistance of the medium in which the pendulum vibrates, is effectually obviated.

Lastly, Experiments on the expansion of wood by heat.

Besides these productions of our celebrated philosopher, we have an oration, on the subject of astronomy, which he delivered before the Philosophical Society, by their appointment, in the year 1775. It is said to have commanded, by its intrinsic excellence, universal admiration and applause, although delivered with a feeble voice, and without any of the advantages of elocution. The dedication is remarkable. To the Delegates of the thirteen United Colonies, assembled in congress at Philadelphia, to whom the future liberties, and consequently the virtue, improvement in science, and happiness of America are intrusted, the following oration is inscribed and dedicated, by their most obedient and humble servant, the Author.'

As we believe that nothing can give a more accurate portrait of a man's mind, than the style in which he expresses his ideas, we hope the following extracts from Dr. Rittenhouse's oration will not be considered foreign to his biography,

After speaking of the false impressions of the solar system, made on the mind, by appearances, uncorrected by science, he introduces this elegant and instructive passage:

How does Astronomy change the scene!- Take the miser from the earth, if it be possible to disengage him; he whose nightly rest has been long broken by the lo s of a single foot of it, useless perhaps to him; and remove him to the planet Mars, one of the least distant from us: Persuade the ambitious monarch to accompany him, who has sacrificed the lives of thousands of his subjects to an imaginary property in certain small portions of the earth; and now point it out to them, with all its kingdoms and wealth, a glittering star “close by the moon," the latter scarce visible and the former less bright than our Evening Star:-Would they not turn away their disgusted sight from it, as not thinking it worth their smallest attention, and look for consolation in the gloomy regions of Mars?

• But dropping the company of all those, whether kings or misers, whose minds and bodies are equally affected by gravitation, let us proceed to the orb of Jupiter; the Earth and all the inferior planets will vanish, lost in the sun's bright rays, and Saturn only remain: He tvo sometimes so diminished in lustre, as not to be easily discovered. But a new and beautiful system will arise. The four moons of Jupiter will become very conspicuous; some of them perhaps appearing larger, others smaller than our moon; and all of them perforining their revolutions with incredible swiftness, and the most beautiful regularity:varying their phases from full to new and from new to full, and frequently eclipsing the sun and each other, at least to the equatorial parts of Jupiter; and almost in every revolution suffering eclipses themselves by falling into Jupiter's shadow; excepting that the outermost will seem, like a traveller fond of the sun-beams, cautiously to avoid the shadow for whole years together. Since we are advanced so far, if not tired of the journey, let us proceed a step further; it is but 400 millions of miles to the globe of Saturn. Here again all will be lost, but Jupiter itself. The Sun will put on something of a starlike appearance, but with excessive brightness. The five satellites of Saturn

will exhibit appearances similar to those of Jupiter, but they will very rarely eclipse the Sun, or suffer eclipses themselves. The particular phenomena of Saturn's ring, we cannot explain, unless we knew the time and plane of Saturn's revolution on his axis. But this we know, that it must sometimes appear, by night, like a prodigious luminous arch, almost equal to one quarter of the heavens; and at other times, dark, so as to afford no light itself, but to intercept the light of every star beyond it, by night, and of the sun itself by day. And to conclude, if borne on the wings of a comet we should travel with it to the remotest part of its orbit; our whole planetary system would disappear, and the sun become a star, only more refulgent than Sirius perhaps, because less distant.'

Those who have read, and consequently admired, the eloquent • Discourses on the Christian Revelation, viewed in connexion with the Modern Astronomy,' by Dr. Chalmers, of Glasgow, will be pleased to meet with the following extract on the same subject, from the oration of Dr. Rittenhouse.

• The opinion of the earth's rotation on its axis was once violently opposed, from a notion of its dangerous tendency with respect to the interests of religion. But, as truth is always consistent with itself, so many new proofs were furnished from time to time by new discoveries, that a mistaken interpretation of some passages in the Bible was compelled to give way to the force of astronomical evidence. The doctrine of a plurality of worlds, is inseparable from the principles of Astronomy; but this doctrine is still thought, by sonie pious persons, and by many more I fear, who do not deserve that titie, to militate against the truths asserted by the christian religion. If I may be allowed to give my opinion on a matter of such importance, I must confess that I think upon a proper examination the apparent inconsistency will vanish. Our religion teaches us what philosophy could not have taught; and we ought to admire with reverence the great things it has pleased Divine Providence to perform, beyond the ordinary course of nature, for man, who is undoubtedly the most noble inhabitant of this globe. But neither religion nor philosophy forbids us to believe that infinite wisdom and power, prompted by infinite goodness, may throughout the vast extent of creation and duration, have frequently interposed in a manner quite incomprehensible to us, when it became necessary to the happiness of created beings of some other rank or degree.

• How far indeed the inhabitants of the other planets may resemble man, we cannot pretend to say. If like him they were created liable to fall, yet some, if not all of them, may still retain their original rectitude. We will hope they do: the thought is comfortable.-Cease, Galileo, to improve thy optic tube: and thou, great Newton, forbear thy ardent search into the distant mysteries of nature: lest ye make unwelcome discoveries. Denrive us not of the pleasure of believing that yonder radiant orbs, tr..sing in silent majesty the etherial regions, are the peareful seats of innocence and bliss: where neither natural nor moral evil has ever yet intruded; where to enjoy with gratitude and adoration the creator's bounty, is the business of existence.'

Dr. Rittenhouse, in continuing this view, now gives it a political direction,

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