SKETCH OF DEN I SON OLMSTED. 405 



and theoretical ones on meteorology. His colleagues and friends 

 have regarded him as a born teacher, as possessing a most happy 

 union of several powers the capacity to convey instruction with 

 clearness and evidence, the capacity to impress the pupil with the 

 importance of the branches taught, the disposition to shrink from 

 no labor necessary in preparing himself for teaching, and to re- 

 quire of the student that he master and reproduce the lessons con- 

 veyed to him. While many lecturers prepare their lectures once 

 for all, and then cease to improve them, he was constantly revis- 

 ing, elaborating, and almost constructing anew the courses on 

 astronomy and meteorology which he delivered annually to the 

 three upper classes." These lectures were spoken of by Dr. Bar- 

 nard, in his Journal of Education, as having been characterized 

 " by fullness, clearness of method, and sometimes by eloquence. 

 The course on meteorology was, perhaps, on the whole, the most 

 attractive and useful." 



Prof. Olmsted soon became sensible of the deficiency of the text- 

 books on which he had to rely in his department. Enfield's Phi- 

 losophy was inaccurate and behind the state of science ; and the 

 work of Prof. Farrar, of Cambridge, was too extensive and too 

 difiicult. He undertook to prepare new books suitable for his 

 classes. His Natural Philosophy appeared in 1831, and his School 

 Philosophy in 1833. His Astronomy, first published in 1839, went 

 through forty or fifty editions. An edition of it was printed in 

 raised letters for the blind, it having been selected by Dr. Howe, 

 according to Dr. Barnard, " for its clear, accurate, comprehensive 

 presentation of the science of which it treats." The Rudiments 

 of Natural Philosophy and Astronomy followed, in 18-42. The 

 Letters on Astronomy was a work in more familiar style, cast in 

 the form of letters to a lady, and prepared as a reading book for 

 the school libraries established by the Massachusetts Board of 

 Education. 



The great meteoric shower of November, 1833, which was ob- 

 served over a large part of the American continent and on the 

 ocean, directed Prof. Olmsted's mind to a new and original field 

 of investigation ; and several papers upon it were published by 

 him and Prof. A. C Twining, of West Point, in the American 

 Journal of Science during 1834. The collation of the collected 

 observations brought out the fact that the apparent point of 

 radiation of the meteors was identical with that toward which 

 the earth was tending in space which indicated a cosmical 

 origin. It was further found that several showers had been ob- 

 served before within forty years, on the same day of November. 

 In explanation of the phenomenon. Prof. Olmsted supposed, in an 

 article published in the American Journal of Science, that the 

 meteors " consisted of joortions of the extreme parts of a nebulous 



