16 DISCUSSION OP THE DISTURBANCES 



Separating into western and eastern disturbances we find 



From which it appears that the easterly values preponderate over the westerly in 

 the ratio of 1.14 to 1. The ratio from the Toronto observations between 1844 and 

 1848 is 1.28 to 1. 



The following table shows the aggregate amount of disturbances in each month 

 of the different years, or the annual inequality of the aggregate disturbances : 



The last column of ratios of the aggregate value of the disturbances of each 

 month to the mean of all, corresponds very closely to the analogous ratios deduced 

 in a preceding table for the number of disturbances, giving the law in reference to 

 the number and amount of disturbances in a year as the same, or nearly so. The 

 maximum amount of disturbances occurs in October (at Toronto in September), 

 the minimum amount in June (the same at Toronto) ; the secondary maximum 

 occurs in April (as at Toronto), and the secondary minimum in February ; but at 

 Toronto in January, from comparison with the years 1843, 1844, 1845. 



The next tables give the aggregate monthly values in the six years, separated 

 into west and east deflections : 



1 The differences of the disturbed readings from their respective normals during the month of June 

 and part of July, 1840, were first converted from the old scale into equivalent new scale values. 



