DAY AURORA. 
319 
self to the apparent wind-movements of our exhibi- 
tions in Lancaster Sound. 
I have quoted the "fog or cloud-like segment" 
as forming a prominent feature in the Continental 
descriptions, for the purpose of introducing from my 
journal two anomalous exhibitions of aurora in the 
same connection. One was in direct conjunction with 
the diffracted solar ray; the other a true daylight au- 
rora. I give them verbatim from my notes. 
February 7. Cold and clear: thermometer, at 8h. 
40m. A.M., at 88°, while on the vessel's stern; and at ^ 
42° when freely suspended by the bows outside: my 
Green's spirit standard, some fifty paces from the ves- 
sel, at —48°: one more illustration of the local influ- 
ences of ship-board, and of the irregularity of our sys- 
tem of registration. 
" The sun was completely visible at about ten 
A.M. ; but his rays were subdued by a slight hazi- 
ness, caused by myriads of crystallized specks that 
filled the atmosphere. These, when examined by 
my traveling Frauenhofer at two hundred diameters, 
gave in some few cases regular hexagonal prisms, 
with well-defined terminations; but this symmetry of 
form was generally obscured by groupings, and long 
oblique truncations. I have now made eight careful 
examinations of these crystalline spiculae at varying 
temperatures, when they came to us accompanied by 
parhelia, halos, or anomalous columns proceeding from 
the sun. In every case there was a decided approach 
to the six-sided form. 
" The sun to-day exhibited an unusual phenomenon. 
At lOh. 20m., while very low, a column of light was 
observed stretching from the upper summit of its disk 
to an approximate height of 15°. This expanded, fan- 
