For the last couple of years I have patiently waited for the ledger books of the Irish Mission for Immigrant Girls in New York City to come online. Well, all of a sudden, there they are! Some of them, anyway. Seemingly, there are more to come.
The website, Watson House, has very quietly gone live. You can now search their records from 1897-1940. The information contained therein is phenomenal: the names of Irish immigrant women, their age, what county in Ireland they came from, their US destination address, and other interesting information.
For 35,000 women! Enjoy.
Claire Santry's Irish Genealogy News has a very comprehensive article about this record set.