v. 



N. America. — Amherst College. — Lat. 42° 22' N. Long. 72° 30' W. Greenw. 



Corrections to be applied to the Means of the Hours of Observation to obtain the true 

 Mean Temperatures of the respective Days, Months, and of the Year. — Dewey. 



Degrees of Fahrenheit. 



The numbers without sign must be added: those with the sign — must be subtracted. 



The above Table has been derived from one year of hourly observations made at Amherst College, 

 Ma.ssachusetts, in 1839, under the direction of Professor Snell, and communicated by Professor Ches- 

 ter Dewey. It gives the simple differences of the monthly means of each hour from the monthly 

 means of the twenty-four hours which are found in the last line. 



E 28 



