104 
COLONEL SABINE ON PERIODICAL LAWS DISCOVERABLE 
the rest, and a body of disturbed observations was thus collected, of which the recog- 
nised characteristic was simply that they were the disturbances of largest amount 
occurring in the whole period. The number of observations thus separated in the 
period commencing July 1, 1843 and ending July 1, 1848*, was at Toronto 3940, 
and at Hobarton 3469, being respectively 1 in 9*43 at Toronto and 1 in 10’55 at 
Hobarton of the whole number of hourly observations. The disturbed observations 
being next distributed into the several hours, months, and years in which they had 
occurred, their numbers and aggregate values in each particular hour, month and 
year, were ascertained. They were then divided into easterly and westerly deflec- 
tions, and the same process of distribution was gone through with each of the two 
divisions. The 7nean hourly, monthly, and yearly numbers and aggregate values in 
the whole period were then taken as the respective units, and the ratios to these units 
computed for each of the hours, months and years ; whereby the relations, whether of 
numbers or of aggregate values in different hours, different months, and different 
years, were shown. The numerical values of this analysis will be found in the second 
volumes of the Toronto and Hobarton Observations, and the ratios only are stated 
here, as it is only the relation inter se of the numbers and values, and not the absolute 
numbers and values themselves, which are required in this discussion. 
I shall proceed to discuss separately, — 1st, the Inequality or variation in the occur- 
rence and aggregate values of the disturbed observations in different hours of the 
day and night ; 2nd, in different months of the year ; and 3rd, in different years. 
I. Inequality or variation in the number and aggregate values of the disturbed 
observations in different hours. 
This examination may be most conveniently made, by separating the disturbed 
observations at once into easterly and westerly disturbances, and classing together,— 
1st, easterly disturbances at Toronto and westerly at Hobarton; and 2nd, westerly 
at Toronto and easterly at Hobarton : an appropriate classification, as the stations 
are in opposite hemispheres, and one which will be seen to be justified by the charac- 
teristics which they respectively present. 
The following Table exhibits the ratios of the numbers and aggregate values, at 
the different hours, in the five years from July 1843 to July 1848, of the easterly dis- 
turbed observations at Toronto and westerly at Hobarton, to the mean hourly number 
and aggregate value of the same taken as the respective units. 
* The period for which the disturbances were examined in my former paper', was from January lS-43 to 
December 1845 inclusive, malcing three complete years. For the present paper I have taken from Juh’- 1843 
to June 1848 inclusive, making five complete years, of which 2|- are part of the period previously examined, and 
2|- are new. 
