£. Loomis— Observations of the U. S. Signal Service. 21 
degrees (Fahrenheit) below the mean, and column second shows 
how much the temperature at Iceland was above or below the 
mean for the same months. It will be seen that for the years 
here named, the average temperature at Vienna in November 
was 4°8 degrees below the mean, while that of Iceland was 1:9 
degrees above the mean; and for the three months compared, 
the temperature at Vienna was 60 degrees below the mean, 
while that of Iceland was 2°3 degrees above the mean. If the 
temperature at Iceland were independent of the causes which 
affect the temperature at Vienna, the average departure from 
the mean temperature at Iceland for the months in question 
should be zero, instead of which we find the value 2°3 degrees. 
Considering that these are the average results derived from 
forty-one years of observations, I thiuk it is established that 
when the temperature of Iceland during the colder months of 
the year is much above the mean, the temperature at Vienna is 
generally depressed below the mean. 
t will be noticed that exceptions to this rule do occasionally 
occur. ‘Thus in December, 1826, 28 and ’34, and in Novem- 
ber, 1870, the temperature was unusually high both at Iceland 
and Vienna; also in November, 1847, and December, 1859, the 
temperature was unusually low both at Iceland and Vienna. 
In December, 1826 and 28, the temperature was above the 
land, i 
Southern or Southeastern Europe, and that during the colder 
months of the year, Vienna is generally near the center of this 
direction of the 
