This is what my research turned up:
Papa and Foula are two Shetland islands. The Horn Of Papa was a headland that eventually fell into the sea.

Here is my attempt at a translation from the Shetland dialect:

Out west of the Horn of Papa
Rowing down beyond Foula
Over a hidden stretch of water
Rowing down beyond Foula

Around the boats is a high tide swell
Sunlight is breaking through the clouds
We must go to where the fish are taking bait
Rowing down beyond Foula

(Fishy knots) where boats have truly
Known no misfortune
We have (towes and bowes and cappies)
Lead shot for ballast
Peat in the kettle for fire
Potato for the pot

Like a laughing, boisterous girl
Courted be her wooers
Papa sometimes lies in summer
Veiled with (ask=mist?) and showers
There upon the wild water
Comes the scent of flowers

We can bide ashore no longer
We must go and try
We'll win back boys if we cannot
See clearly through the murk
For the scent of flowers in Papa
Leads us all the way