Chemistry and Physics. 106 
ut p.m.; and the author suggested the probability that the anomalies 
which have sometimes been supposed to exist in the tu f 
force at the two stations, (which is the antagonistic force opposing all 
Magnetic variations,) whilst on the other hand the increase in the range 
_ of the disturbance variation is many times greater than it would ‘be ae- 
= Cording to the same proportion, It would appear, therefore, that the 
absolute disturbing force must be greater at Point Barrow that at Toronto. 
SS The author then proceeded to point out the concomitant occurrences 
the auroral manifestations, The observers noted at each hour whether 
not there was an auroral display: from 11 A.M. to 3 P.M. no auroral 
displays were ever observed ; but the number of them was found progres- 
| sively to increase from 3 p.m. to 1 a.M., and then again in regular pro- 
Session to decrease to 0, at 11 a.m. The frequency of the occurrence 
of the aurora may be judged of, when it is said that during six months, 
Pal 9-53, and the same 
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found at the same hour of westerly disturbance—viz. 1 a.m. The fre- 
qteney of the aurora, also, and the arnount of westerly deflection of the 
e uso accord ; whilst on the other hand the auroral in ton 
9 have little ith the turning hours or the pro- 
_.» Were taken into account, there could remain no doubt that such 
» Hons had been made and recorded, and that these records still ex- 
iy some of the places he had last been in. When he (General 
the he) was with Capt. Parry, in 1818, they had made observations with 
Shasta, um for determining the figure of the earth, and others of great 
been: a Importance, on their way towards Behring’s Straits. They had 
‘posed to considerable risk of the ships being lost, and were about 
‘he boats and proceed overland, and in preparation for this 
hs ly prepared to carry with them abstracts of the observations, leaving 
“OND SERIES, VOL, XXV, NO. 73.—JAN., 1858, 
14 
