as the column rises, however, the rays of the sun reach its
sides, striking obliquely upon them under the boulder, and wearing them
away, until the column becomes at last too slight to sustain its burden,
and the rock falls again upon the glacier; or, owing to the unequal
action of the sun, striking of course with most power on the southern
side, the top of the pillar becomes slanting, and the boulder slides
off. These ice-pillars, crowned with masses of rock, form a very
picturesque feature in the scenery of the glacier, and are represented
in many of the landscapes in which Swiss artists have endeavored to
reproduce the grandeur and variety of Alpine views, especially in the
masterly Aquarelles of Lory. The English reader will find them admirably
well described and illustrated in Dr. Tyndall's work upon the glaciers.
They are known throughout the Alps as "glacier-tables"; and many a time
my fellow-travellers and I have spread our frugal meal on such a table,
erected, as it seemed, especially for our convenience.

Another curious effect is that produced by small stones or pebbles,
small enough to become heated through by the sun in summer. Such a
heated pebble will of course melt the ice below it, and so wear a hole
for itself into which it sinks. This process will continue as long as
the sun reaches the pebble with force enough to heat it. Numbers of such
deep, round holes, like organ-pipes, varying in size from the diameter
of a minute pebble or a grain of coarse sand to that of an ordinary
stone, are found on the glacier, and at the bottom of each is the pebble
by which it was bored. The ice formed by the freezing of water
collecting in such holes and in the fissures of the surface is a pure
crystallized ice, very different in color from the ice of the great mass
of the glacier produced by snow; and sometimes, after a rain and frost,
the surface of a glacier looks like a mosaic-work, in consequence of
such veins and cylinders or spots of clear ice with which it is inlaid.

Indeed, the aspect of the glacier changes constantly with the different
conditions of the temperature. We may see it, when, during a long dry
season, it has collected upon its surface all sorts of light floating
materials, as dust, sand, and the like, so that it looks dull and
soiled,--or when a heavy rain has washed the surface clean from all
impurities and left it bright and fresh. We may see it when the heat and
other disintegrating influences