686 SIR Gr. B. AIRY ON RESULTS DEDUCED FROM THE MEASURES 
Monthly Means of Daily Range of Horizontal Magnetic Force at Greenwich 
Mean Daily Range of Horizontal Force in the Direction of Astronomical Meridian. 
Month. 
Range of 
Meridian 
Force. 
In Gottingen Mean Solar 
Time. 
Approximate Hour of 
Month. 
Range of 
Meridian 
Force. 
In Gottingen Mean Solar 
Time. 
Approximate Hour of 
Minimum 
Meridian 
Force. 
Maximum 
Meridian 
Force. 
Minimum 
Meridian 
Force. 
Maximum 
Meridian 
Force. 
h. 
m. 
h. 
m. 
h. 
ni. 
h. 
m. 
January . . 
•0019 
1 
10 
20 
0 
June . . . 
•0031 
22 
50 
9 
50 
. 
July . . . 
•0026 
23 
10 
7 
0 
December . . 
•0020 
3 
0 
19 
0 
January . . 
•0019 
1 
0 
19 
0 
June. . . 
•0021 
23 
40 
8 
0 
July . . . 
•0024 
0 
0 
18 
0 
December . . 
•0012 
23 
10 
19 
0 
January . . 
■0014 
0 
0 
19 
0 
June . . . 
•0020 
0 
0 
18 
0 
July . . . 
•0022 
1 
0 
18 
0 
December . . 
•0015 
2 
0 
19 
0 
January . . 
•0014 
1 
0 
19 
0 
June. . . 
•0023 
23 
10 
17 
30 
July . . . 
•0020 
0 
20 
19 
0 
December . . 
•0013 
2 
0 
20 
0 
! January . . 
•0020 
0 
30 
20 
0 
June. . . 
■0027 
0 
0 
18 
0 
July . . . 
•0025 
o 
0 
18 
0 
December . . 
•0020 
0 
0 
19 
0 
In Greenwich Mean Solar 
In Greenwich Mean Solar 
Time. 
Time. 
J anuary . . 
•0024 
1 
0 
18 
0 
June. . . 
•0037 
23 
50 
16 
30 
• 
July . . . 
•0033 
23 
0 
16 
40 
December . . 
•0023 
0 
0 
18 
0 
Januaiy . . 
•0028 
0 
o 
17 
30 
June. . . 
•0032 
0 
0 
17 
0 
July . . . 
•0031 
1 
0 
16 
0 
December . . 
•0023 
0 
0 
18 
0 
January . . 
•0026 
1 
0 
17 
0 
June . . . 
•0034 
22 
40 
6 
30 
July . . . 
•0035 
23 
50 
13 
0 
December . . 
*0020 
0 
0 
17 
0 
January . . 
•0031 
0 
0 
18 
0 
June. . . 
•0025 
0 
10 
7 
0 
July . . . 
Ohser 
vations 
inter 
rupted. 
December . . 
•0021 
0 
0 
18 
0 
January . . 
•0014 
0 
0 
17 
0 
June . . 
•0028 
22 
50 
8 
0 
July . . . 
•0024 
20 
0 
6 
0 
December . . 
•0014 
0 
0 
18 
0 
January . . 
•0014 
23 
0 
17 
0 
June . . . 
•0033 
23 
0 
6 
0 
July . . . 
•0028 
22 
40 
7 
30 
1 
December . . 
•0013 ! 
0 
0 
10 
30 
Year. 
1853- 
1854< 
1855 
1856 
1857< 
1858< 
1859 
1860< 
1861 - 
1862 ■< 
1863- 
1864 
Observations interrupted during construction of the Magnetic Basement. 
Gottingen Mean Solar Time is greater by 40 m than 
