f^the Shetland Islands. S55 
reaching the highest step of the flight of stairsj there appeared 
no reason for supposing that any roof had ever protected- the 
summit of the building, so that the Burgh of Mousa must have 
been originally nothing more than a circular mural shell, open 
to the top. The height of the inside wall was S5 feet, being 7 
feet less than that of the outside ; this difference was partly 
owing to the accumulation of stones and earth, which had filled 
the inner courts 
The mode was now evident in which this Burgh had been 
intended to give security to the persons and property of the 
ancient inhabitants of Shetland against the sudden landing of 
predatory adventurers. The tiers of apartments contained 
within the thick walls would afford a shelter to women and 
children from the missile weapons of assaulters, besides being 
repositories for grain and other kinds of property, as well as 
for the stores whereby a long siege might be sustained. The 
low narrow door within the court, which admits of no entrance 
but in a creeping posture, might be easily secured at a short 
notice by large blocks of stone. It has been remarked of the 
rude forts similar to these which occur on the shores of Scandi- 
navia, that they were seldom taken by an enemy, unless by 
snrprise, or after a long blockade ; that frequently terraces and 
artificial banks were raised near that side of the wall which 
was the lowest, and that the besieged were then annoyed with 
arrows, stones, boiling-water, or melted pitch, being thrown in- 
to the fort ; — offensive weapons which they did not neglect to 
return. The history of the Burgh of Mousa confirms the cor- 
rectness of this observation ; its high walls bulging out from 
their foundation, defied any attempt to scale them ; for, when 
they were encompassed by one of the Earls of Orkney, he had 
no hopes of inducing the fortress to surrender, but by cutting 
off all supplies of food, and then waiting the event of a long 
siege. Altogether the building was well adapted for resisting 
the attacks of the ancient piratical hordes of these seas, who, 
from the short summers of northern latitudes, and from the in- 
capability of their vessels to sustain a winter'’s navigation, durst 
not allow themselves to be detained on the coast by any tedious 
operations of assault. 
