46 PITYSICAL GEOGRAPHY OF THE SEA. 
From afar, the small island of Staffa, rising precipitously from 
the sea, seems destitute of all romantic interest, but on ap- 
proaching, the traveller is struck with the remarkable basaltic 
columns of which it is chiefly composed. Most of them rest 
upon a substratum of solid shapeless rock, and generally form 
colonnades upwards of fifty feet high, following the contours of 
the inlets or promontories, and overtopped with smaller hillocks. 
Along the west coast of the island they are tolerably irregular, 
but on the south side Staffa appears as an immense Gothic 
edifice, or rather as a forest of gigantic pillars seemingly ar- 
ranged with all the regularity of art. The admiration they 
cause is, however, soon effaced when the vast cave to which the 
remote islet owes its world-wide celebrity bursts upon the view. 
Fancy a grotto measuring 250 feet in length by 53 in width at 
the entrance, and spanned by an arch 117 feet high, which, 
though gradually sloping towards the interior, still maintains a 
height of 70 feet at the farthest end of the cavern! The walls 
consist of rows of huge hexagonal basaltic pillars, which seem 
regularly to diminish according to the rules of perspective. 
The roof of the vault is formed of the remnants of similar 
columns, whose shafts have beyond a doubt been torn away by 
the sea, which, destroying them one after the other, has gra- 
dually excavated this magnificent temple of Nature. All their 
interstices, like those of the pillars, are cemented with a kind of 
pale yellow spar, which brings out all the angles and sides of 
their surfaces, and forms a pleasing contrast with the dark 
purple colour of the basalt. 
The whole floor of the cave is occupied by the sea, the depth 
of which, even at its farthest end, is above six feet, during ebb- 
tide ; but it is only in perfectly calm weather that a boat is able 
to venture into the interior, for when the sea is any way turbu- 
lent (and this is generally the case among the stormy Hebrides) 
it is in danger of being hurled against the walls of the grot and 
dashed to pieces. Under these circumstances, the only access 
into the cave is by a narrow dyke or ledge running along its 
eastern wall, about fifteen feet above the water. It 1s formed of 
truncated basaltic pillars, over which it is necessary to clamber 
with great caution and dexterity, as they are always moist and 
slippery from the dashing spray. Frequently there is only 
room enough for one foot, and while the left hand grasps that 
