A search on Google provides many references to Coffin Ships that carried emigrants escaping famines or clearances in Ireland or Scotland to distant lands.
Wikipedia has a long article on coffin ships. The first papagraph offers a succinct description: “A coffin ship (Irish: long cónra) is a popular idiom used to describe the ships that carried Irish migrants escaping the Great Irish Famine and Highlanders displaced by the Highland Clearances.[1]” https://en.wikipedia.org/wiki/Coffin_ship
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