124 M. Rose on the Combinations of 
from Greenwich = 108° 6’. If now we place these three de- 
terminations together, we obtain : 
Distance from Long. W. from 
. the Pole. Greenwich. 
1730 19°15! 108° 6! 
1769 19 43 100 2 
1813 22 50 92 24 
Which distinctly shows that this magnetic pole has also a per- 
ceptible motion towards the east; and it seems also to follow 
that it moves away from the terrestrial pole. From the year 
1730 to 1796, z.e. within 39 years, it has moved 8° 4’, or 12/41 
in every year more east; from 1769 to 1813, z.e. within 44 
years, this motion amounted to 7° 38', or 10!41 annually. 
Whether this difference arises from an inequality in the motion 
or an error in the observation, we must leave to the decision 
of future generations. 
As the northern pole of the magnetic needle is directed to- 
wards this point in the whole of North America, we seem to 
be justified in concluding, that if we were to travel round it 
with a compass, the needle would in that time make a com- 
plete revolution. If then we are south of this point, the 
northern pole of the needle will point due north, or in other 
words, there will be no variation at all on this spot: to the 
north of it the northern pole would point to the south, or the 
declination would be 180°; to the east of it the declination 
would be 90° W., and to the west it would be 90° E. The 
justness of this conclusion is proved from the observations of 
Captains Ross and Parry in the years 1818, 1819 and 1820, 
some of which are marked on the chart. Most of these arrows, 
as may be seen, are directed to one point; and the situation of it 
in the year 1820 might be determined in the manner described 
above. As these observations are very important for the theory, 
and we may probably have no speedy opportunity of making 
observations in these inaccessible parts, I shall proceed to give 
the most remarkable of them. 
[To be continued.] 
XX. On the Combinations of Antimony with Chlorine and Sul- 
phur. By M. Henn Rose*. 
I, Combinations of Antimony and Chlorine. 
W HEN pulverized antimony is distilled with an excess of 
c 
orrosive sublimate, it is known that there is obtained a 
solid compound of antimony and chlorine, which melts at a very 
* From the Annales de Chimie, tom. xxix. 
moderate _ 
