SURVEY OF BELGIUM IN 1871 
348 
Table II. (continued). 
Station. 
Date. 
G.M.T. 
Dip. 
Needle No. 1. 
Needle No. 2. 
Needle No. 3. 
Mean. 
1871. 
h m 
[ 
Terriers 
Aug. 23 
8 40 a.m. 
66 47 8 
10 15 ., 
66 40 55 
1 1 35 „ 
66 44 17 
Liege 
25 
7 45 „ 
66 29 47 
2 50 r.M. 
66 28 28 
„ 26 
9 35 a.m. 
66 29 0 
Aix-la- Chapelle 
„ 26 
4 30 r.M. 
66 38 17 
5 45 „ 
66 43 49 
„ 2S 
9 10 a.m. 
66 36 8 
Spa 
29 
8 10 
66 40 34 
9 30 
66 41 11 
11 0 „ 
66 39 15 
66 40 20 
Avion 
„ 31 
8 45 „ 
65 56 23 
10 10 „ 
65 55 1 7 
11 10 ,, 
65 55 4 
Namur 
Sept. 2. 
8 40 
66 35 34 
9 40 
66 29 19 
10 50 ,, 
66 35 21 
Mons 
„ 4. 
2 45 r.M. 
66 33 29 
3 50 .. 
66 38 39 
4 50 
66 34 20 
66 35 29 
Tournay 
c. 
3 10 ,, 
66 42 15 
4 20 „ 
66 38 34 
5 25 „ 
66 36 4 
66 38 58 
Corn-tray 
„ 7. 
3 30 " 
66 41 25 
4 35 „ 
66 38 19 
„ 8. 
7 45 a.m. 
66 45 38 
66 41 47 
Client 
„ 8. 
3 20 r.M. 
67 13 34 
„ 10. 
8 0 a.m. 
67 14 12 
9 18 ., 
67 15 15 
67 14 20 
Ostend 
., 11. 
4 35 r.M. 
67 14 20 
5 25 „ 
67 16 26 
12. 
4 15 „ 
67 10 19 
67 13 42 
Bruges 
„ 13. 
9 16 A.M. 
67 14 35 
11 10 
67 7 21 
14. 
4 40 p.m. 
67 9 4 
67 10 20 
Tronehiennes 
„ 15. 
3 30 „ 
67 21 35 
4 30 „ 
67 22 35 
.. 16. 
67 23 47 
67 22 39 
Alost 
., 18. 
3 14 r.M. 
67 15 28 
4 15 „ 
67 11 12 
,. 19. 
9 34 a.m. 
67 14 0 
67 13 33 
Brussels, 131 rue Boyale 
„ 20. 
4 50 p.m. 
67 9 8 
„ 23. 
8 35 a.m. 
67 6 39 
., 25. 
7 45 . 
0/ 2 51 
67 6 13 
Brussels Observatory 
’ 22. 
10 35 „ 
67 1 21 
2 0 p.m. 
66 58 12 
3 5 „ 
©* ! 
67 0 12 
Expressing the mean values in decimals of a degree, and subtracting 65° from each, 
we obtain the equations required for determining the distance apart, and the inclination 
to the meridian, of the lines of equal Dip. 
1- 657 =& — 75-U-— 6% 
2- 226=a + U-4a?+ 5-9 y 
2-022=0— l-4a-+25-4 y 
0- 926=^-63-6^-80-8 y 
2-172=<5+49-8.t+24% 
1- 696=^+47-6^- 2-5// 
2- 239=S+28-(k+13% 
2 z 2 
