The Zentralbibliothek Zürich (Central Library Zurich) was founded in 1914 (as an merging of different libraries). This is the old Stamp the Library used. Its big, a circle surrounding the city coat of arms, as well as the name of the library. The version in this picture is even done with an embossing punch on the outisde of a bunded volume of a magazine (the “Deutsche Monatsschrift für Rußland”)
This version is another embosser, this time in black.
This version used the same design as the embosser punchs, but this time its a stamp on the first page of a book.
Sometime in their existence the library altered the stamp. (the one today is way much smaller.) This one is still big, but it used a much smaller design of the city coat of arms, but filled most the gained place with the name of the library.
As with every big library, the quality of the stamp is very different on different documents, as you could see by comparison of the version and the version in the picture above of the same stamp.