Comics, as Chris Ware has repeatedly stated, is a visual language. It is more than just text and pictures. It is not literary prose.
This distinction between comics as a visual language and literary prose needs some work to explain it though I think it's the case.
In the Morning News Tournament of Books, Natasha Vargas-Cooper recently reviewed a YA novella and Chris Ware's Building Stories. Ware lost.
He lost because Vargas-Cooper read his comic as if it were text and pictures; she clearly prefers text.
Read this essay closely and you'll see exactly, with precision and clarity, how not to read comics.
Two excellent discussions of the visual language of comics can be found in Scott McCloud's Understanding Comics and Will Eisner's Comics and Sequential Art.