Additions extend the building to the rear, providing space for modern stacks and services.

It grew over the rest of the 19th century by the gifts of other collections, and was at first housed in the Welch Building at Charles and Moody Streets.

In 1894, Francis Buttrick, then the city's largest landowner, bequested funds for the construction of a permanent home.

The oldest portion of the building was designed by the Boston firm Loring & Leland, and was completed in 1915, it having taken twenty years to locate and acquire a suitable parcel of land.

A gallery space was added in 1933,[2] and a modern addition made to the rear later in the 20th century.