Someone on one of the Irish lists graciously did a look-up for us in the book:
"Irish Emigration Lists 1833-1839" by Brian Mitchell (1989,
Genealogical Publishing Co, Inc., ISBN 0-8063-1233-5)
This book only shows emigration from ANTRIM and LONDONDERRY/DERRY from 1833 to
1839.
The following CASSIDYs were found:
Frank, age 30, from Mullan Townland, Kilrea Parish, Co. Londonderry, to New
York in 1834. Roman Catholic.
Frank, age 24, from Fallagloon Townland, Maghera Parish, Co. Londonderry,
to New York in 1834. Roman Catholic.
James, age 24, from Gaol Lane Townland, Coleraine parish, Co. Londonderry,
to Quebec in 1834. Roman Catholic.
James, age 20, from Garbagh Townland, Errigal Parish, Co. Londonderry, to
Quebec, in 1834. Roman Catholic.
Robert, age 24, from Ballygruby Townland, Artrea Parish, Co. Londonderry,
to Quebec in 1834. Roman Catholic.
Hope this helps someone!
Janet C-S