LXIX. 639 



Russia. — Petersburg. Lat. 59° 56' N. Long. 30° 18' E. Greenw. 



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

 Mean Tennperatures of the respective Days, Months, and of the Year. — Dove. 



Degrees of Reaumur. 



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



75 



