]ii CAPTAIN ELLIOT’S MAGNETIC SURVEY OF THE INDIAN ARCHIPELAGO 
Mean Hourly Oscillation of the Horizontal Intensity in the 
Astron. Mean Time. 
12 . 
13. 
14. 
15. 
16. 
17. 
18. 
19. 
20. 
1 21. 
22. 
September 
0-09 
0-39 
0-71 
0-89 
0-94 
0-85 
1-23 
2-44 
4-37 
5-95 
6-80 
October 
0-28 
0-61 
0-62 
0-87 
0-98 
0-92 
0-99 
1*99 
3-91 
5-83 
7-02 
December 
0-11 
0-30 
0-41 
0-73 
0-66 
0-69 
0-87 
1-81 
3-36 
4-88 
5-95 
Sums 
0-48 
1*30 
1-74 
2-49 
2-58 
2-46 
3-09 
6-24 
11-64 
16-66 
19-77 
Means 
0-16 
0-43 
0-58 
0-83 
0-86 
0-82 
1-03 
2-08 
3-88 
5-55 
6-59 
Oscillation 
0-15 
0-42 
0-57 
0-82 
0-85 
0-81 
1-02 
2-07 
3-87 
5-54 
6-58 
Mean Hourly Oscillation of the Horizontal Intensity 
Winter 
0-13 
0-13 
0’35 
0-41 
0-53 
0-60 
0-94 
1-61 
2-91 
4-51 
5-83 
Spring 
0-07 
0-21 
0-29 
0-36 
0-48 
0-57 
0-92 
1-97 
3-75 
5-57 
7-01 
Summer 
0-08 
0-24 
0-32 
0-29 
0-48 
0-62 
1-25 
2'29 
3-80 
5-10 
6-09 
Autumn 
0-15 
0-42 
0-57 
0-82 
0-85 
0-81 
1-02 
2-07 
3-87 
5-54 
6-58 
Sums 
0-43 
1-00 
1-53 
1-88 
2-34 
2-60 
4-13 
7-94 
14-33 
20-72 
25-51 
Means 
0-11 
0-25 
0-38 
0*47 
0-58 
0-65 
1-03 
1-98 
3-58 
5-18 
6-38 
Oscillation 
0-09 
0-23 
0-36 
0-45 
0*56 
0-63 
1-01 
1-96 
3-56 
5-16 
6-36 
Mean Hourly Oscillation of the Horizontal Intensity 
December 
0-18 
0-35 
0-49 
0-73 
0*75 
0-76 
1-11 
1-91 
3-20 
4-56 
5-70 
January 
0-34 
0*11 
0-42 
0-36 
0-50 
0-61 
1-12 
1-72 
2-92 
4-30 
5-8 1 
February 
0-01 
0-09 
0-29 
0-29 
0-50 
0-59 
0-74 
1-36 
2-75 
4-82 
6-14 
March 
0-23 
0-39 
0-37 
0-45 
0-57 
0-59 
0-61 
1-43 
3-13 
5-07 
6-56 
April 
0-00 
0-20 
0-48 
0‘6l 
0-73 
0-82 
M2 
2-35 
4-28 
6-34 
8-12 
May 
0*16 
0-21 
0-21 
0-19 
0-31 
0-49 
1-21 
2-32 
4-03 
5-49 
6-52 
June 
0-03 
0-07 
0-17 
0-18 
0-22 
0-35 
1-00 
2-06 
3-46 
4-84 
5-84 
July 
0-12 
0-22 
0-32 
0-21 
0-49 
0-72 
1-33 
2-37 
3-83 
5-12 
5-94 
August 
0-19 
0-53 
0-57 
0-57 
0-81 
0*89 
1-52 
2-54 
4-19 
5-43 
6-57 
September 
0-09 
0*39 
0.71 
0-89 
0-94 
0*85 
1-23 
2-44 
4-37 
5-95 
6-80 
October 
0-28 
0-6 1 
0-62 
0-87 
0-98 
0-92 
0-99 
1-99 
3-91 
5-83 
7-02 
November 
0-11 
0-30 
0-41 
0'73 
0-66 
0-69 
0-87 
1-81 
3-36 
4-88 
5-95 
Sums 
1*74 
3-77 
3-06 
6-08 
7-46 
8-28 
12-85 
24-30 
43-43 
62-63 
76-97 
Means 
0-14 
0-31 
0-42 
0-51 
0-62 
0-69 
1-07 
2-02 
3-62 
5-22 
6-41 
Oscillation 
0-08 
0-25 
0-36 
0-46 
0-56 
0-63 
1-01 
1-96 
3-56 
5-16 
6-35 
Mean Oscillation of the Horizontal Intensity at Singapore 
1843 
0-06 
0-22 
0-31 
0-35 
0-49 
0-54 
0-94 
1-90 
3-38 
4-94 
6-17 
1844 
0-12 
0-21 
0-40 
0-38 
0*58 
0-62 
1-07 
1-97 
3-51 
5-00 
6-09 
1845 
0-13 
0-29 
0-45 
0-53 
0-69 
0-79 
1-10 
2-09 
3-86 
5-60 
6-86 
Sums 
0-31 
0-72 
M6 
1-26 
1-76 
1-95 
3-11 
5-96 
10-75 
15-54 
19-12 
Means 
0-10 
0-24 
0-39 
0*42 
0-59 
0-65 
1-04 
1-99 
3-58 
5-18 
6-37 
Oscillation 
0-09 
0-23 
0*38 
0-41 
0-58 
0-64 
1-03 
1-98 
3-57 
5-17 
6-36 
Comparison of Horizontal Intensity in minutes of Arc between the Fixed 
Bifilar Portable 
2'- 19 
2'-13 
1'’90 
2'-63 
3'-22 
5'-19 
6'-62 
8'-45 
Bifilar Fixed 
0 -88 
0 *75 
0 -61 
1 -00 
1 -35 
4-02 
6 -04 
8 -70 
