368 
COLONEL SABINE ON PERIODICAL LAWS DISCOVERABLE 
the horizontal force about 2*7 as great, and in the vertical force about five times as 
great. 
But in the ratios of the Declination-disturbances at the different hours shown in 
the preceding Table, we have the joint effects of two classes of disturbances, those 
which produce easterly and those which produce westerly deflections ; and in the 
ratios of the disturbances of the horizontal and vertical forces at the different hours, 
we have the further complication, that the variations of the horizontal and vertical 
forces do not bear a simple relation to those of their theoretical equivalents to which 
they are due, viz. the Inclination and Total Force, but involve quantities dependent on 
the resolution of forces, which, when the Inclination is great, as it is at Toronto, have 
a tendency to mask the simplicity of the variations of the Inclination and of the Total 
Force, as they would appear if they were the subjects of direct observation. In the 
following Table therefore are placed the proportions at the different hours in which 
the six classes of phenomena respectively vary, viz. the disturbances which produce 
easterly and those which produce westerly deflections, those which increase and 
those which decrease the Inclination, and those which increase and those which 
decrease the Total Force. * 
Table IV. 
Toronto 
Astronomical 
Hours. 
Disturbances 
Toronto Civil 
Hours. 
of the Declination producing 
of the Inclination producing 
of the Total Force producing 
Easterly 
Deflection. 
Westerly 
Deflection. 
Increase of 
Inclination. 
Decrease of 
Inclination. 
Increase of 
Force. 
Decrease of 
Force. 
18 
0-45 
1-82 
0-82 
0-83 
0-27 
1-91 
6 A.M. 
19 
0-35 
2-23 
1-29 
0-51 
0-26 
1-91 
7 A.M. 
20 
0-26 
2-58 
M4 
0-62 
0-37 
M2 
8 A.M. 
21 
0-21 
2*25 
1-05 
1-37 
0-22 
0*65 
9 a.m. 
22 
0-28 
1-62 
0-96 
1-47 
0-25 
0-28 
10 A.M. 
23 
0-39 
I'Ol 
0-89 
1-80 
0-39 
0-07 
11 A.M. 
0 
0-24 
0-80 
0-93 
1-75 
0-67 
0-04 
Noon. 
1 
0-21 
0-41 
0-87 
1-70 
1-25 
0-10 
1 P.M. 
2 
0*20 
0-65 
0-65 
1-92 
1-79 
0-08 
2 P.M. 
3 
0-22 
0-62 
0-71 
1-36 
2-21 
0-06 
3 P.M. 
4 
0-32 
0-80 
0-61 
1'46 
2-77 
0-07 
4 P.M, 
5 
0-44 
0-71 
0-79 
1-35 
2-96 
0-07 
5 P.M. 
6 
1-05 
0-57 
1-04 
0-72 
2-39 
0-07 
6 P.M. 
7 
1-44 
0-39 
M4 
1-02 
2-56 
0-09 
7 P.M. 
8 
1-95 
0-28 
1-12 
0-55 
1-99 
0-09 
8 P.M. 
9 
3-09 
0-22 
1-17 
0-58 
1-23 
0-31 
9 P.M. 
10 
2*41 
0-45 
1-18 
1-39 
0*81 
0-83 
10 P.M. 
11 
2-02 
0-27 
M9 
0-84 
0-53 
M9 
11 P.M. 
12 
1-76 
0-82 
MO 
0-85 
0-46 
2-14 
Midnight. 
13 
1-79 
M9 
1-32 
0-70 
0-26 
2-57 
1 A.M. 
14 
1-37 
1-00 
1-33 
0-37 
0-22 
2-70 
2 A.M. 
15 
1-28 
0-94 
1-05 
0-48 
0-28 
2*81 
3 A.M. 
16 
1-48 
1-21 
0*90 
0-48 
0-18 
2*48 
4 A.M. 
17 
0-91 
1-23 
0-76 
0-55 
0-28 
2-24 
5 A.M. 
We learn from this Table, that the laws which regulate the occurrence of easterly 
and westerly disturbances are not, on the one hand, similar, nor, on the other hand. 
