V. 



N. America. — Frankfort Arsenal. Lat. 39° 57' N. Long. 75° 8' 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. — Dove. 



Degrees of Fahrenheit. 



E 



The numbers without sign mus' be added ; those with the sign — must be subtracted. 



18 



