Complex sentence: The Guibord case (see below) and the events of 1869 to 1874 marked the final decline of the Institut, and in 1871 the Institut closed its debating room, and in 1880 closed its library.
Split into simpler sentences: The Guibord case (see below) and the events of 1869 to 1874 marked the final decline of the Institut. In 1871 the Institut closed its debating room, and in 1880 closed its library.