( M3 ) 
V, A Letter from Dr, Hallet, Phy/ician at Exe- 
ter, to Dr. Henry Pemberton, F. R, S, on • 
Ctoh. 3, 1716, at Nine in the Evening, I faw an 
Aurora Borealis (as ’tis commonly call’d, > in 
which there was nothing different from former Appea- 
rances, excepting that from the luminous Arch which 
appear’d in the North, were frequently fliot off Parts of 
Arches towards the Zenith, which vanifli’d there. 
0 ^. 8, Coming from the Country near Seven in the 
Evening, I obferv'd a great Light in the Eaft and Wed, 
which foon extended it felf over our Heads, the North 
and South appearing dark at the fame time. No Cloud 
w^as feen all that Day. A great Dew fell on a fudden, 
with which the Streets were wet, as by a fmall Rain. 
Half an Hour after Seven many Streams appeared in 
the North, vyhich grew very bright, and darted fre- 
quently up to the Zenith. A Line drawn through the 
Bafes of them, made an Arch of a Circle, extending 
from the N. E. to the W. or S. W. But the Streams 
feemed to proceed from a clear Sky being diffindf from 
one another at the Bafes, and not united by a luminous 
Arch or Cloud, as in the more ufual Aurora's, The 
Streams at the two Extremities of the Arch were bright- 
er, wider and longer when they did not ffioot, than thofe 
on the Top of it. [See Fig. i.] There was at the fame 
time a luminous Arch extending it felf from the two 
Extremities of the above-mention ’d Aurora through the 
South, at a confiderable Altitude. About Eight o’ 
the fame Subje6l 
Exon, O^oh, IX, 1716. 
T X 
clock 
