150 
Lieut . Foster’s observations on the diurnal changes 
North end of Needle to the S. W. 
IV 
Date. 
lean Time 
of Obser- 
Al. m. 
or 
Reading of j 
north end of 
Temp. 
ahren*. 
Direction of 
north end of 
needle during 
westerly daily 
variation. 
'ime that a ho- 
rizontal needle 
took to make 
60 vibrations. 
Winds. 
Weather. 
Remarks, &c. 
vation. 
P. M. 
Needle. 
Instr. 
1825 . 
Mar. 4th 
h. m, 
10 40 
11 5 
II IO 
II 50 
0 30 
1 OO 
2 OO 
2 5 
■f 2 IO 
2 35 
2 38 
3 00 
A. M .5 
P. M. 
O ! 
5 45 00W 
45 20 
46 20 
46 20 
47 10 
47 20 
47 40 
50 00 
50 25 
50 25 
49 30 
49 5 
47 40 
47 00 
46 30 
46 OO 
45 10 
45 5 
45 0 
45 0 
44 5 ° 
44 4 ° 
44 50 
44 5 ° 
44 5 ° 
44 5 ° 
0 
— 26 
— 26 
— 26 
—26 
— 26 
—25 
—25 
—25 
—25 
—25 
—25 
—25 
—25 
—2 5 
2_C 
t 3 
c 
A 
•• <£ 
QJ 
<D 
* C rG • * 
4 -* 
O 
m. s. 
17 59>7 
17 56,3 
17 51,8 
17 5°,5 
17 50 
17 56,2 
Calm 
Ditto 
Max. westerly 
variation. 
3 32 
4 OO 
4 5 
Easterly 
Light 
Fine clear 
4 7 
5 10 
6 3 
* J 
—25 
“25 
— 26 
®® 0 OOQO 9 
17 5 8 >5 
i 7 54>3 
17 55’9 
1 7 53>3 
17 49 
17 45 >6 
17 5°>7 
17 55 > 8 
weather 
7 6 
7 5 ° 
9 00 
— 26 
—27 
—261 
........ 
— 9 3 o 
IO IO 
2 
—27 
—27 
—271 
—275 
—271 
Easterly 
Light 
Veryclear 
Max. easterly 
10 50 
and fine 
variation. 
II 30 
II 56 
North end of Needle to the N. W. 
In this case, the ends of the magnets nearest the needle were 29,4 inches from the centre of the com- 
pass-box, and the time of performing one vibration by the needle thus circumstanced was 14,4 seconds, 
so that the directive force now, was to the undiminished force as 0,15 to 1. 
Mar. 5th 
2 IO 
2 30 
3 OO 
3 10 
3 15 
3 20 
4 OO 
5 10 
6 6 
7 6 
A.M. 
N 48 00W 
48 00 
48 10 
49 10 
50 OO 
50 30 
51 30 
52 OO 
51 30 
51 30 
52 OO 
50 IO 
49 00 
48 40 
49 00 
48 30 
47 00 
— 26 
—26 
■ — 26 
— 26 
—26 
—26 
— 26 
— 26 
— 26 
. — 26 
-d 
c 
. . pG . • 
4 -J 
rG 
'u 
<D 
. . O .9 
.. H .. 
17 58 
17 59>3 
18 7 
18 0,5 
17 59 > 8 
18 5,0 
Easterly 
Light 
Westerly 
moderate 
Hazy 
Thick & 
Hazy 
+ 7 5 ° 
9 3 ° 
10 30 
I I OO 
—26 
18 1,8 
— *5 
— 26 
17 55-5 
17 5 i> 2 
17 52,3 
17 4 8 >5 
Calm 
Clear anc 
I Max. westerly 
— 26 
fine 
variation. 
1 1 30 
11 35 
Noon 
— 26 
— 26 
—25 
•••••••* 
