What puts "The Poison Oracle" considerably above most books of its kind is its thoroughness of detail. Dickinson, as might be expected from the author of so scary and offbeat a novel as "Sleep and His Brother" … has an unusual kind of mind. He also is a first-rate researcher who seems to know a great deal about Arabic languages, linguistic theory and Arabic customs. Thus "The Poison Oracle" transcends the pure mystery. But between the covers is a classic mystery with a more or less standard denouement except for the chief witness—the most unlikely witness any writer is going to introduce for a long time. (p. 31)

Newgate Callendar, in The New York Times Book Review © 1974 by The New York Times Company; reprinted by permission), June 16, 1974.