Account of a Halo observed at Pictou, Nova Scotia. 67 
the brightest parts being most deeply shaded. It was crowned 
by the two ares BD, which cut the circle A, and each other 
in the point (a), producing an appearance of flattening or 
depression at that point. These arcs were prismatically 
coloured, and faded toward their extremities. 
“The are C wasshort and broad, well defined at its convex 
margin, but fading towards its concave margin and extre- 
mities. It was coloured, the yellow ray predominating. 
“The ares D E were brightly coloured, and appeared to 
have their convex sides towards the sun. They had much 
the aspect of fragments of rainbows. 
“The large horizontal circle F, passing through the sun’s 
centre, was of a milky whiteness. This circle retained its 
perfect form for a very short time, and the portion nearest the 
sun was always the most clearly defined. The smaller hori- 
zontal circle g was the last part of the halo in order of de- 
velopment, and was very transient. It was white, and ex- 
tremely faint.” 
It will be observed, on comparing these descriptions, that 
the arcs B B were seen at the Albion Mines as parts of one 
circle, somewhat flattened at the point where it touched the 
halo A. At Pictou, they seemed to be arcs of two circles, 
each of about the same diameter with A. At Pictou, how- 
ever, their apparent length was much less than at the Mines. 
The circle g was not seen at the Albion Mines. These dis- 
erepancies may possibly have been due to the small differ- 
ence of elevation and latitude between the stations. 
After the disappearance of the other circles and ares, the 
circle A, crowned with portions of the ares BB, still re- 
mained, though it gradually became less distinct. After the 
disappearance of the horizontal circles, the stratum of cirrus 
lost its curdled appearance, and was replaced by a more 
dense and uniform veil, with straight fibres, the wind at the 
same time changing to north-east. Towards evening a few 
ragged cumuli formed beneath the cirrous veil. On the fol- 
lowing day the wind was still north-east, and the sky overcast, 
threatening rain; but only a very few ‘drops fell. For some 
time before the 23d, the weather had been dry and warm. 
The northerly wind, which accompanied and followed the halo, 
caused a slight fall of temperature. 
