- "The percontation-mark (or punctus percontativus), the standard Arabic question mark, indicated 'percontations,' questions open to any answer or (more loosely) 'rhetorical questions,' in various books of c.1575-c.1625. This usage seems to have been invented by the translator Anthonie Gilbie or his printer Henry Denham (a pioneer of the semi-colon): roman examples appear in their psalms of Dauid (1581), black letter ones in Turberville's Tragicall Tales (1587). It didn't catch on in print because, being reversed, expensive new type was needed, but was used by scribes including Crane, who worked on Shakespeare's First Folio: so how did compositors set percontation-marks present in their copy but not type-cases? One possibility is that italic or black letter question-marks amid roman type record otherwise unsettable percontation-marks."
(John Lennard, The Poetry Handbook: A Guide to Reading Poetry for Pleasure and Practical Criticism. Oxford Univ. Press, 2005)
- "[Henry] Denham seems to have been interested in punctuation, since two of the books he published in the 1580s contain another new, but rare symbol, the percontativus . . .. This consists of a reversed, but not inverted, interrogativus and is used to mark a percontatio, i.e. a 'rhetorical' question, one which does not require an answer. . . . For the most part 16th- and 17th-century authors and compositors either omitted to mark a percontatio, or used the interrogativus, but the percontativus does appear from time to time in the 17th century: for example, in the holographs of Robert Herrick and Thomas Middleton."
(M.B. Parkes, Pause and Effect: An Introduction to the History of Punctuation. Univ. of California Press, 1993)