I was quite excited at the prospect of reading this book. The storyline appeared fascinating and I quickly read the first hundred pages. After this, some tedium set in, caused by the fact that every other chapter is set in the present, in a story that makes some sense, whereas the intervening chapters are all set somewhere in the past, between 1000 years ago and recent past, and it is not clear on reading them how much detail one has to absorb.
For instance, many of the intervening stories involve new characters, unconnected with anything else, and it is too easy to regard them as just displaying one facet of the history of the objects at the core of the story. So, you disregard the details of the names of their characters and then realize later that perhaps one (or several) of these characters are still in the present (or are they? or are they all the same character??). Then, the real reason for the strange goings on in the present turns out to be only marginally relevant to the history of the objects in the Geographer's Library after all.
The ending of this novel is far from satisfying, and I was confused about what had actually happened. If there is a consistent story behind this novel then it has not been told very well. Compare this novel with "Shadow of the Wind", where a confusion of present and past is masterfully resolved, to see the difference between a fair and a great novel.