286 EXTERNAL APPEARANCE OF GLACIERS. 
ately beneath it from the action of the sun ; and 
as the level of the glacier sinks all around it, in 
consequence of the unceasing waste of the sur- 
face, the rock is gradually left standing on an 
ice-pillar of considerable height. In proportion 
as the column rises, however, the rays of the sun 
reach its sides, striking obliquely upon them un- 
der 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 slant- 
ing, and the boulder slides off. These ice-pillars, 
crowned with masses of rock, form a very pic- 
turesque feature in the scenery of the glacier, 
and are represented in many of the landscapes 
in which Swiss artists have endeavored to repro- 
duce 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, es- 
pecially for our convenience. 
Another curious effect is that produced by 
small stones or pebbles, small enough to become 
