How important soever, in relation to astronomy, the phænomena observed by Mayer may be, the honour of first discovering them certainly belongs to him. Mr. Rittenhouse was not the discoverer: nor had he ever access to so complete and expensive an astronomical apparatus, as that used by Mayer on the occasion, and with which he was furnished by means of princely munificence. But all candid men of science will, nevertheless, be disposed to allow the American Astronomer no inconsiderable share of merit for the early “presage,” which his deep-discerning and vastly comprehensive mind enabled him to suggest, of some such future discoveries.
The writer of these memoirs deemed it his duty to do justice to the memory of the subject of them, by giving publicity to these interesting circumstances; and the performance of this duty is the more gratifying to the writer, because he alone possesses a knowledge of all the facts he has stated, concerning them.
The late discoveries of Dr. Herschel, among the fixed stars, in addition to those previously made by Mr. Mayer, have in a greater degree realised the expectations which were formed, many years before either, by our Astronomer; such, indeed, as are almost entitled to the character of prescient annunciations, respecting that portion of the heavens which should, some time or other, be the scene of the most important astronomical discoveries. According to Herschel, the Milky Way is an immense nebula, near one of the sides of which, is placed the solar system; and he imagines, that each nebula, of which he had observed more than nine hundred, consists of a group of suns, with their attendant planets!
Mr. Rittenhouse never possessed the means of acquiring such stupendous and costly telescopes, as those used by Herschel, for the purpose of exploring the heavens. But the penetrating genius of our countryman seems to have contemplated, by anticipation, the actual existence of those sublime phænomena, some of which the vastly superior instruments of the Germano-Anglican Astronomer have since manifested; when, in language apparently prophetic, but certainly dictated by the most exalted pre-conceptions of the grandeur of celestial objects which were yet undiscovered, the American Philosopher observes, as he does in his Oration,—that “all yonder stars innumerable, with their dependencies, may perhaps compose but the leaf of a flower in the Creator’s garden, or a single pillar in the immense building of the Divine Architect.” Well might he exclaim, with rapturous extacy, after so beautiful and sublime a reflection,—“Here is ample provision made for the all-grasping mind of man!”
It will be evident to such as duly reflect on this subject, that those expectations which occupied the mind of Mr. Rittenhouse, so long since as the year 1775—concerning the “amazing discoveries” which should, at some future period, be made among the fixed stars, were not mere conjectures or vague hypotheses; but, that they were rational anticipations of realities, founded on the most acute observation and laborious research, as well as the profoundest philosophical judgment. As Newton is said to have revealed those truths in physics, which his predecessor, Bacon, had preconceived; so, that great practical astronomer, Herschel, and some other eminent observers of our day,[[230]] have been enabled, by means of the very important improvements recently made in astronomical instruments,[[231]] to verify a grand hypothesis in his favourite science, which had long before been conceived by the towering genius of Rittenhouse.
From the time our astronomer became established in Philadelphia, until the year 1787, he resided in a house belonging to the late Mr. Thomas Clifford, at the south-east corner of Arch and (Delaware) Seventh streets: But the mansion which Mr. Rittenhouse had erected for himself, the preceding year, on his Observatory-lot at the diagonal corner of those streets, being then compleated, he removed thither; and there continued his residence, during the residue of his life. It was about this time, perhaps towards the close of the year 1786, that he was compelled by the duties of his office, as sole trustee of the loan-office, to put in suit the bonds which accompanied the mortgages of sundry delinquent loanees. The bonds were placed in the hands of the Writer of these Memoirs, for that purpose; with instructions to treat the delinquents with every reasonable degree of forbearance. This lenity was observed, agreeably to Mr. Rittenhouse’s desire; few suits were instituted, and payment of the monies due, or the greater part of them, was not long after obtained.
Early in the year 1787, the expected appearance of a new comet in that year, engaged Mr. Rittenhouse’s attention: and on that occasion he addressed the following letter to Mr. Ellicott.
“Philadelphia, Feb. 12, 1787.
“Dear Sir,
“The elements of the new Planet have been pretty well determined by several European astronomers. The following I have extracted from the Almanack[[232]] for 1787.