580 



III. 



NORTH AMERICA. PHILADELPHIA. Lat. 39 58' N. Long. 75 1 1' 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. GUYOT. 



Degrees of Fahrenheit. 



16 



