1815.] " ' Dr. Rlttenhoiise. 163 



Gentleman had received a regular university education, and pos- 

 sessed considerable knowledge and abilities. He was two years 

 older than Mr. Rittenhouse, and two years afterwards became his 

 brother-in-law by marrying his sister. An intimate friendship took 

 place between these two young men ; and there can be no doubt 

 that Mr. Barton must have been of considerable use in forwarding 

 the education of Mr. Rittenhouse, both by supplying him with 

 books, and by instructing him in several branches of knowledge, to 

 ■which previously he could not have the means of paying any atten- 

 tion J but we neither know the course of study that Mr. Ritten- 

 liouse pursued, nor the books which he used. He appears early to 

 have acquired a very considerable knowledge of mathematics and 

 astronomy, and to have perused Newton's Principia partly in the 

 English translation and partly in the original. Mr. Barton says 

 that he discovered the method of Auctions without knowing that it 

 bad been previously discovered by Newton ; but such ignorance in 

 the year \']o\, more than half a century after the discovery was 

 publicly known in Europe, seems hardly conceivable. Whatever 

 mathematical books he studied must have alluded to a method at 

 that time followed by every mathematician ; or supposing, which 

 seems hardly credible, that all the books in his possession had been 

 printed before the discovery of Auctions, still Mr. Barton, who had 

 been educated at Trinity College, Dublin, could not possibly be 

 ignorant of the discovery of Auctions. Indeed, in the second 

 edition of the Principia, there is a kind of discussion on the subject 

 by Newton himself. Mr. Baiton then, I conceive, must have been 

 misinformed upon this subject. 



Astronomy was Mr. Rittcnhouse's darling pursuit ; and we have 

 the strongest proofs that his knowledge of this science was pro- 

 found, and his skill as a practical astronomer very great. He 

 acquired considerable dexteiity in making astronomical instruments, 

 especially telescopes and clocks. Tlie principles by means of which 

 the pendulums of these clocks were kept always at the same length 

 are curious, and deserve the attention of astronomers and mathe- 

 matical instrument-makers. 



But though neither the books which he perused, nor the order of 

 liis studies, be known, yet we are acquainted with the particular 

 ( ircumstance which first turned his attention to mechanics and 

 iJiathematics. He had a maternal uncle, David Williams, a car- 

 penter, wlio had a mathematical turn : this man died when David 

 Kitteiihouse was a boy, and iiis tools and books, consisting of some 

 trtatibcb on geometry and some mauuscrijjt calculations, fell into 

 the |x>sse9sion of his mother; to these books, &c. David had free 

 access, and they were probably the only books of any value within 

 his reach. Hence we need not be surprised that a young man of a 

 vigorous understanding soon acquired a taste for mathematics, and 

 Iciinied to handle ilie tool.- of iiis ancle. 



The great mailiemalical and astronomical skill of Mr. Ritten- 

 house uus hoon diicovered Ly Mr. liarton, who had taken orders, 



L 2 



