9 
eighteen to thirty pounders, besides se¬ 
veral very large field-pieces. It com¬ 
mands the north entry to Bressay Sound, 
and is garrisoned by a small detachment 
of invalids. 
In the neighbourhood of this town 
there is a chalybeate spring, but it is 
not much esteemed for its medical vir¬ 
tues. 
Bressay Sound lies between Lerwick 
and Bressay Island, and forms an exten¬ 
sive and commodious harbour, in which 
vessels well found may ride at all seasons 
in the greatest safety. 
Here the Dutch herring fleet used to 
rendezvous about the middle of June. 
This harbour has the particular advan¬ 
tage of two entries, one from the souths 
and another from the north. 
On the outside of the north entry lies 
a sunk rock, called the Unicorn. On 
this rock was wrecked the Unicorn man- 
of-war sent out in pursuit of the Earl of 
