From the American Mathematical Society (AMS) News 2007: "Readers may now view online the first century of the Bulletin of the American Mathematical Society, from 1891 to 1991, searchable and fully integrated with the modern Bulletin [more...]."

The archive (1891-1991) is also freely available at Project Euclid. It was digitized by the Digital Mathematics Library Project of the Mathematical Sciences Research Institute (MSRI), with funding from the Gordon and Betty Moore Foundation. The Mathematics Statistics Library at Berkeley also donated one of its sets of the Bulletin to this worthwhile project.