where the writers are
coffin ships
Below decks on a coffin shipl

According to Edward Laxton's The Famine Ships, 5000 ships left Ireland during the first six years of the Famine. About half the emigrants sailed to New York giving that city more Irish than Dublin.
The cost of sailing to America was roughly twice that of passage to Canada, so for the landlord the choice was an easy one. Money rules. American ships were faster and better constructed. They allowed more room for the passengers.