CXXV111 
APPENDIX. 
OBSERVATIONS on the Variation, made at Sea, in H. M. S. Hecla, 1819, continued. 
1819 
Latitude 
Longitude 
Ship’s Head 
Obser- 
ver 
VARIATION, WEST 
REMARKS 
O / 
O / 
0 
/ 
r 
p 
67 23a 
July 10 
69 03 K 
57 58 w 
North 
>67 49.5 
1 
B 
68 16J 
14 
70 08 
58 00 
N.N.E.^E. 
B 
64 55 
r 
P 
69 ISA 
.-The true variation observ- 
| 
I ed on the ice in latitude 
ie 
70 43 
59 25 
N.E. 
B 
67 34j-68 47 
|70° 29', and longitude 
H 
69 33 J 
159° 12' was 74° 39'. 
( 
N.byE. 
P 
72 32 
21 
72 56 
58 37 \ 
B 
70 56) 
[ 
N.N.E. j 
>71 05.5 
1 
H 
71 15) 
N.67 W. 
H 
99 42 
( 
r 
B 
92 04i 
22 
73 13 
60 15 ^ 
N.2S W. \ 
>91 18.5 
1 
l 
H 
90 33) 
On the 24th of July, the ship being enclosed by extensive fields of ice, and 
having just water sufficient to admit of her head being warped round on the 
different points of the compass, a series of Observations were made corre- 
sponding to those of the 4 th of May, in the River Thames. 
The needle of Walker’s Azimuth Compass, which had been hitherto in use, 
had now become so sluggish and uncertain in its direction that it was 
removed, and a card, which had been sent on trial by Mr. Jennings, patentee 
of the Insulating Compasses, substituted in its place ; this card was furnished 
with two needles crossing each other at right angles, the division of North 
on the card being intermediate between the North Poles of the Needles. 
Mr. Jennings had conceived that such a compass might possibly be affected, 
by the disturbing influence of the ship’s iron, in a different manner from 
other compasses ; but this did not prove the case, its results differing from 
those obtained with one of Captain Kater’s Azimuth Compasses, not more 
than such observations will differ on repetition, with the same compass in 
ships in high magnetic latitudes ; Mr. Jennings’s Card, however, notwithstand- 
ing the weight of the two needles, and of the card itself, which was a heavy 
one, traversed much better than Mr. Walker’s, and was continued in ordinary 
use until the ships had ascended Barrow’s Straits ; when, from the near 
