“The novel is being compared with abandon in the press to the ”Harry Potter” books, but it is not for children, unless they are children who really, really love footnotes. It is nearly 800 pages long, but in some ways that number feels arbitrary, as if the novel consisted of just those pages Clarke chose to show, and that she might have easily chosen another 800 from those she kept in reserve. She has lived in the world of the novel for more than a decade after all, carefully charting the false history of English magic and documenting it with citations from a fastidiously false bibliography. What did not make it into the main story is alluded to in copious notes that make up sort of a second novel at the bottom of its pages (when they do not take over the pages altogether).” (New York Times Magazine)