[110]. Jeremiah Horrox and William Crabtree, two Englishmen, were the observers of the Transit of Venus of 1639.
[111]. It was not until the year 1786, that Mr. Rittenhouse built the house at the north-west corner of Arch and (Delaware) Seventh streets, in Philadelphia, where he resided during the remainder of his life: but probably it was some few years earlier that he erected his Observatory, a small but pretty convenient octagonal building, of brick, in the garden adjacent to his dwelling-house. Its situation was not an ineligible one, when the building was first put up: but its commodiousness and utility were probably much diminished, by the erection, not long afterwards, of some large houses near it; and it is presumable, that its usefulness in any degree, for the purposes of an Observatory, could have continued but a little while beyond the duration of its late proprietor’s life, by reason of the rapid increase of the number of lofty houses in the vicinity. Indeed it lately became extremely probable, on considering the great enlargement of Philadelphia within the last twenty-five years, that the future augmentation of the population and extension of improvements in this beautiful and hitherto flourishing city, would, in a very few years, render the late Observatory of Mr. Rittenhouse wholly useless for astronomical purposes; and, in the event of the surrounding ground and adjacent buildings being alienated from his family, improper for any other.
This was the Observatory noticed by Mr. Lalande, when (in his Astronomie, published in 1792,) he made this remark, treating of the numerous Observatories in different parts of the world—“In America, I know of no Observatory but that of Mr. Rittenhouse at Philadelphia.”
The Observatory at Norriton, mentioned in the text, was a temporary erection; and was disused on his removal to Philadelphia, soon after. The one put up in the State-House Gardens in that city on the same occasion, was likewise a temporary edifice, constructed of wood.
[112]. On an address of the Philosophical Society to the general assembly, dated the 15th of October, 1768, the latter “Resolved, That a sum, not exceeding one hundred pounds sterling, be provided and appropriated for purchasing a reflecting telescope with a micrometer, for the purpose mentioned in the said address” (observing the Transit of Venus, then near at hand,) “and, afterwards, for the use of the house; and that the speaker do write to Benjamin Franklin, Esq. in London, to purchase the same.”
[113]. On a similar address of the Philosophical Society, dated the 7th of February, 1769, the assembly granted them one hundred pounds, “to be laid out towards defraying the expenses necessary for observing the (then) ensuing Transit of Venus.” This grant was made on the 11th of February, 1769.
But the sum then granted proving very inadequate to the object, the society petitioned the assembly on the 11th of February, 1773; stating, that the erecting the different observatories, fitting up instruments, engraving various plates, and publishing the different transit papers alone, cost the society near 400l. and praying assistance to discharge that debt.
[114]. Mr. Lalande, in the preface to his Astronomie (3d edit. 1792,) mentions, that he did not then know of any other observatory in America than that of Mr. Rittenhouse.
[115]. This was one instance among many of the munificence of Mr. Penn to the College of Philadelphia, and of his zealous wish to promote the interests of science in Pennsylvania. The trustees of the college say, in a letter written to Mr. Penn the 1st of August, 1769, thanking him for his donation of the fine instrument above mentioned, together with a pair of “Adams’s new-invented Globes;” “We have likewise the pleasure to acknowledge a fresh instance of your benevolence, in sending us a chemical apparatus under the care of Dr. Rush.” “The many great and valuable favours this College has received at your hands, have always been conferred in a manner which has rendered them peculiarly acceptable; and cannot fail to leave the most lasting impressions of gratitude and esteem in the heart of every person concerned in the institution.”
[116]. Mr. Lalande (in his Astronomie) has been careful to mention, that the celebrated astronomer Hevelius possessed a similar merit. He constructed, himself, the very large telescopes and other instruments, described (with plates) in his great work entitled, Machina Cœlestis, and with which he furnished the Observatory that he established at his own residence, in the year 1641. Hevelius (whose true name was John Hoelké.) was the son of a brewer; but was well educated. He was born at Dantzic the 28th of January, 1611: and after having made the tour of England, France and Germany, from 1630 to 1634, he was, on his return to his native city, occupied for some time in the affairs of that little republic; of which he officiated as consul, in 1651. He died on the anniversary of his birth-day, at the age of seventy-six years.