This song is called "The Prisoner" my Dad has it on an LP by Paddy Noonan and his Grand Band. The song is sung by Mike "Jesse" Owens

The Prisoner

The judge said, "Stand up lad and dry up your tears
You're sentenced to Dartmoor for twenty-one years."
So dry up your tears love and kiss me good-bye
The best friends must part love, so must you and I

I hear the train coming, 'twill be here at nine
To take me to Dartmoor to serve out my time
I look down the railway and plainly I see
You're standing there waving your good-bye to me

Six months have gone by love, I wish I were dead
This dark, dreary dungeon and stones for my head
'Tis raining, 'tis hailing, the moon gives no light
Now you will tell me, love, why you never write

I've counted the days love, I've counted the nights
I've counted the footsteps, I've counted the lights
I've counted the raindrops, I've counted the stars
I've counted a million of these prison bars

So come all ye young fellows with hearts loyal and true
Don't trust any woman, you're a fool if you do
Don't trust any woman no matter what kind
For twenty-one years, lads, is a very long time