You will need a Boston Public Library card to log in, free and available to all Massachusetts residents. If you don't already have one, you can get an eCard , and upgrade this to a standard card if you visit the BPL in person.
that this list omits databases to which BU also subscribes.
The BPL has numerous lists (PDF) to help patrons locate items in their extensive microfilm collections. listed on the guide Newspapers @ the BPL.These include:
Compiled Newspaper sets include civil war clippings; James A. Garfield Papers; William McKinley Papers; and the Great Boston Fire of 1872, among others.
Commercial Microfilm sets include:
The Boston Public Library has always been the best area source for newspapers domestic and foreign - one of the major newspaper collections in the country. It has a rare collection of original newspaper files, in addition to an extensive collection on microfilm. (Visitors should keep in mind that the majority of files are stored off site, and several days should be allowed for retrieval.)
Please also note that, except in rare cases, users will be required to use microfilm copies of the files, provided the Library owns microfilm of the newspaper.
Their excellent research/ finding guide is Newspapers @ the BPL.