Just a quick email as I have only just started my family tree.
Leonard Macarthy was my great grandfather, his daughter Mona was my grandmother, she had two sisters Dorothy and Edith.
Mona married Lt.William Cay Williams in 1918 in London (Marylebone) but divorced in 1923. Sadly William died in 1925 in a plane crash while training out of RAF Digby in a Bristol Fighter. Mona later married Alfred Maeder in 1932 in St Martin, London.
I've managed to trace back to Eugene Macarthy born in 1786 in Limerick and have sort of found his descendents but have a few discrepancies now after having read your posting. I think i am missing either a first or second marriage.
I've been trying to track down the shipping company in Newcastle and have so far come up with Clapham Shipping Company but not sure if this is accurate. I've also found some reference to ships which have reference to George Eugene Macarthy.
As i have said, it's early days but when the birth certificates come through i can clarify a lot and will update you if you are interested.
All the best
Carlene Leonard (nee Williams)