Bolter and Grusin are especially careful to integrate discussion of the visual material into their book at the right spot. Unfortunately, the price of leaving such a wide margin for notes is high. I only mention this because given the subject of the book, I find it surprising that MIT Press would cut corners at the most immediate interface, the printed word. If you have to strain to simply decode it, the printed word won't mediate anything. There are fundamental rhetorical questions one should bring to bear on our selection of mediating forms.
Media does more than remediate other media.
It also communicates to people, or not.