Two Samuel Johnson-based dictionaries from 1828 give 'mariner' basically the modern pronunciation. See https://books.google.com/books?id=z3kKAAAAIAAJ&pg=PA451#

Two Samuel Johnson-based dictionaries from 1828 give 'mariner' basically the modern pronunciation. See https://books.google.com/books?id=z3kKAAAAIAAJ&pg=PA451#v=onepage&q&f=false https://books.google.com/books?id=z3kKAAAAIAAJ&pg=PA451#v=on... and https://books.google.com/books?id=EXEUPL_Jv2MC&lpg=PA61&ots=ZucmU-gmML&dq=johnson%20walker%20dictionary%20pronunciation%20guide%20accent%20marks&pg=RA30-PA5#v=onepage&q&f=false https://books.google.com/books?id=EXEUPL_Jv2MC&lpg=PA61&ots=...