{p. 221}

Southern Cross, nor the feet of Centaur--are visible. It is
frequently almost impossible to discover the position of the moon. If
by chance the outlines of the sun's disk be visible during the day,
it appears devoid of rays."

Says Croll:

"We have seen that the accumulation of snow and ice on the ground,
resulting from the long and cold winters, tended to cool the air and
produce fogs, which cut off the sun's rays."[1]

The same writer says:

"Snow and ice lower the temperature by chilling the air and
condensing the rays into thick fogs. The great strength of the sun's
rays during summer, due to his nearness at that season, would, in the
first place, tend to produce an increased amount of evaporation. But
the presence of snow-clad mountains and an icy sea would chill the
atmosphere and condense the vapors into thick fogs. The thick fogs
and cloudy sky would effectually prevent the sun's rays from reaching
the earth, and the snow, in consequence, would remain unmelted during
the entire summer. In fact, we have this very condition of things
exemplified in some of the islands of the Southern Ocean at the
present day. Sandwich Land, which is in the same parallel of latitude
as the north of Scotland, is covered with ice and snow the entire
summer; and in the Island of South Georgia, which is in the same
parallel as the center of England, the perpetual snow descends to the
very sea-beach. The following is Captain Cook's description of this