504 THE POPULAR SCIENCE MONTHLY. 



As a teacher he was laborious and enthusiastic, and his success 

 was remarkable. He secured the respect and love of his pupils to a 

 degree seldom equalled ; but he was also a zealous student in science, 

 and published several valuable works as the results of his researches. 

 Among these are his " Analytical Geometry," and his " Conic Sec- 

 tions," which, at one time, were extensively used as text-books in our 

 colleges. While connected with the Fellenberg Institution, he pub- 

 lished two works on book-keeping, that were adopted by the State 

 schools of Massachusetts. He read many valuable papers before the 

 American Association for the Advancement of Science, of which he 

 was, from its organization, a member ; and also before the National 

 Academy of Science, for the recent meeting of which he had in prepa- 

 ration an article on the Storm-curve, the object being to show that it 

 was an hyperboloid, the equation of which he had computed. 



His chief reputation, in science, was achieved by his researches in 

 the department of meteorology. These were commenced in 1839, 

 while Principal of the Ogdensburg (N. Y.) Academy. He took simul- 

 taneous and constant observations of the barometric changes connected 

 with the variations of the wind-vane and with the fall of rain. His 

 instruments were self-registering. Each motion of the vane directed 

 a minute but constant stream of dry sand into some one of 32 station- 

 ary hoppers, corresponding in position to as many points of compass. 

 The weight of sand found in the several receptacles below each hopper 

 showed the length of time that the vane had pointed in that direction. 

 The rain-gauge was an inverted cone, having an horizontal surface of 

 172.8 square inches : the rain falling into it passed down, through an 

 orifice so small that no appreciable evaporation could occur, into a 

 close-fitting can. One inch of rain in depth would, therefore, make 

 ^ of a cubic foot when collected, the weight of which is 100 ounces. 

 Each ounce that the can contained after a storm, consequently, repre- 

 sented y^-g- of an inch in perpendicular fall. The amount necessary 

 to merely moisten the funnel without precipitation into the can is 

 easily determined as a constant. The results of these observations for 

 the year 1838 were published by Prof. Coffin in the Meteorological 

 Register, a monthly journal, of which he issued the first number in 

 January, 1839. It was devoted to the discussion of various phenom- 

 ena connected with physical science. Though the demand for a peri- 

 odical of this nature was insufficient to sustain it, it brought into cor- 

 respondence many who were interested in such subjects. The investi- 

 gation of rainfall and evaporation had present practical value in being 

 made the basis of the report of the committee of the New York Senate, 

 in 1839-40, appointed to consider the enlargement of the canal system 

 of the State by the construction of the Genesee Valley Canal. These 

 studies were afterward extended to form the chapter on the climate of 

 the State, published in the " Natural History of New York," in 1845, 

 in which the inquiries took a wider range ; and questions of vegeta- 



