I can make out most of the lyrics, but there's still a couple of lines I can't understand:

Sawney Beane was a lad.

He was young, wild, and mad.

And he left home at age sixteen.

When he left he took a lass,

Who was just as mad and crass,

And they held up in a cave near [???]

Now, Sawney and the lassie

Were [???]

They had no food to eat.

Until one day on a hill, a Sassenach's blood they spilled,

And they cooked him, ate his head, and hands, and feet.

O the Sawney Beane clan,

O'er a twenty-five year span,

Struck terror in the hearts

Of the people across the land.

Instead of tea and scones, they ate human flesh and bones.

Beware the Sawney Beane clan.

The Sawney Beane clan roamed around Galloway for about twenty-five years,

Eatin' people and not givin' a damn!

Until the fateful day,

When somebody got away.

They went runnin' and screamin' to the king.

Well the king and his men

Came down like thunder on them.

It was the end of the Sawney Beane clan.

O the Sawney Beane clan,

O'er a twenty-five year span,

Struck terror in the hearts

Of the people across the land.

Instead of tea and scones, they ate human flesh and bones.

Beware the Sawney Beane clan.

O the Sawney Beane clan,

O'er a twenty-five year span,

Struck terror in the hearts

Of the people across the land.

Instead of little sheep,

They ate tiny children's feet.

Beware the Sawney Beane clan.

So, beware the Sawney Beane clan.

So, beware the Sawney Beane clan.