THE ICE-BARRIER. 
75 
daik clouds of a stormy day, their dead white walls and inky-black crevices, their icy-cold 
breath wafted by the gale, make the spectator shudder. A snowy cliff sketched on this day 
affords a good illustration of the manner in which the bergs were originally built up by 
successive accumulations of snow. The white mass is seen to be traversed by a series of 
delicate blue lines, sometimes hardly visible, sometimes 
increasing to a blue band of the same tint as that 
of the more strongly-defined caves. These lines form 
successive sets or layers, in which the distance between 
the bands is seen to diminish from top to bottom. 
This rhythmical arrangement, evidently the expression 
of a mathematical formula, affords a clue to their origin. 
While the intervals between them decrease from the top 
to the bottom in the several strata of snow of which the 
berg seems to be composed, the bands in the lower strata 
are so close together as to form almost a single layer, 
of a bluish and more transparent, in fact a more ice-like 
substance. What we behold is the gradual transfor¬ 
mation of snow into ice owing to the partial melting of 
the former through the heat developed by the pressure of 
the overlying strata, and the subsequent freezing of the 
of these delicate blue lines upon the face of the cliff is admirable, and imparts an additional 
beauty to the mass. That the density of the different layers of a berg increases rapidly from 
the top towards the bottom, may be concluded not only from the rapidly increasing number 
of blue bands, but also from the manner in which the cracks visible upon the face of 
the cliff, as sketched above, are suddenly arrested by an evidently harder layer. A remarkable 
example of a berg in which strata 
of snow are seen alternating with 
strata of ice—in this case the bands 
were rather of a dark-green colour 
—was observed on the 16th. The 
vast fragment had every appearance 
of having formed part of the 
submerged foundation of a berg. 
In this case the irregular arrangement of the bands of ice seems to be the effect of lateial 
pressure resulting from the concussion of contending masses. 
The general impression produced upon the Antarctic explorer by these floating masses 
of ice, which are known to strew the whole Southern Ocean from the Antarctic Circle down 
to the 40th parallel—some of them have been seen in the immediate vicinity of the Cape of 
Good Hope—is, comparatively speaking, that of great antiquity. Sir James Ross estimates 
ICEBERG SEEN FEBRUARY 16th, 4 p. m. 
ICE-CLIFF SKETCHED FEBRUARY 2I£t ( 4 p*m. 
partially melted snow. The effect 
