you missed a line, Joe. It's often I sailed to Bonny Ram's Island arm in arm with Phelimy Diamond
and I missed a verse. I don't know if this is exactly what the singer performed on the Mudcat session

'Twas pretty to be in Ballinderry,
'Twas pretty to be in Aghalee
Still prettier to be on bonny Ram's Island
Sitting forever beneath a tree.
For often I sailed to bonny Ram's Island,
Arm in arm with Phelimy Diamond [or Phelim, my diamond?]
He would whistle and I would sing,
And we would make the whole island ring.

"I'm going," he said, "from bonny Ram's Island
Out and across the deep blue sea,
And if in your heart you love me, Mary,
Open your arms at last to me."

'Twas pretty to be in Ballinderry
But now it's as sad as sad can be,
For the ship that sailed with Phelimy Diamond,
Is sunk forever beneath the sea.

chorus/caoin (keen)
ochón, ochón, ochón, ochón [alas]

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Rams Island is in Lough Neagh in the north of Ireland, so I suppose it is very small