It's most probable that ships embarking from Tralee and Limerick would have been sail powered. By 1870 or so, the large ocean liners began to ply the seas carrying thousands of passengers. Much safer, much healthier, much shorter passage time, more professional, steerage class probably roomier and probably cheaper. Most who lived near Cork met the Liverpool ships as the "topped off" their load at Cobh. Most other Irish after that probably went to Liverpool to catch the big ships.