George Keller of Hartford was the architect for the building which first opened on March 6, 1889. At the time it was built, the structure went no farther than the north-south corridor of alcoves. The Great Hall, additional stacks, and the back alcove, also designed by Keller, were added in 1911, again the gift of Isabella Eldridge. [Website]
This view is from the railway. Still in use as a public library.