I guess my first clue that I was going to have problems finishing this book should have been when I went to collect it from the library and discovered it was not, as I had expected, a 352-page trade paperback but instead a 352-page hardback printed in a tiny font with loads of whitespace on every page.
I very much enjoyed the introduction to the book and also the first few chapters, which were about ancient written languages which have been translated successfully - Egyptian hieroglyphics, Linear B and (most recently) Mayan glyphs. The introduction talks about the things you need in order to make it more likely that a language can be deciphered if no longer used and that was interesting in itself.
Then we got into chapters about those scripts which have yet to be deciphered, either because nobody can figure out what language they represent or because there is just so little of them currently in existence that they can't be studied effectively. This was where I got lost, as the book goes into much more detail on those than I was able to get my head around. I guess I was looking for something a little more accessible than this proved to be?