THE INCORPORATOKS 169 



at that time removed to Boston, and young Peirce assisted him 

 in reading the proofs of his translation of Laplace's Mecanique 

 Celeste. 



For two years after his graduation, Professor Peirce taught 

 at Northampton, Massachusetts. In 1831, he was appointed a 

 tutor in Harvard College, and in 1833 was elected Professor of 

 Mathematics and Natural Philosophy. Afterwards he was 

 called to the Perkins chair of mathematics and astronomy, which 

 he occupied until his death. 



During the first years of his professorship, he published a 

 series of text-books for use in colleges. The first was a " Treatise 

 on Sound," and was followed by one on " Plane and Solid 

 Geometry," a " Treatise on Algebra," and a treatise on " Plane 

 and Spherical Trigonometry." These books produced very 

 beneficial effects on the methods of teaching mathematics. 



In 1841, Professor Peirce began a work on " Curves, Func- 

 tions and Forces," two volumes of which appeared at intervals. 

 In place of the third volume, he published in 1855, his 

 " Analytic Mechanics." This was rather a treatise than a text- 

 book, and exhibits in a striking manner Peirce's peculiar mathe- 

 matical powers, and his concise and logical style. In 1842, he 

 began work on the mathematical part of the " American 

 Almanac," of which he prepared ten volumes. One of these con- 

 tained a list of the known orbits of comets, to which he added 

 several approximate orbits for historic comets that had been 

 imperfectly observed. 



In 1849, Congress established a bureau for the publication 

 of the " American Ephemeris and Nautical Almanac," under 

 the supervision of Admiral (then Lieutenant) Charles H. Davis, 

 and Professor Peirce was appointed consulting astronomer. To 

 his work while in this position may be attributed largely the 

 high character which this publication attained. For it he pre- 

 pared his " Tables of the Moon," which were used for many 

 years. After the discovery of the planet Neptune, Professor 

 Peirce took great interest in the researches of Leverrier and 

 Adams, and his papers written on the disputed questions regard- 



