A Fifteenth Century Instrument for Computing the Quantity of Verses in Latin Hexameters and Pentameters

摘要

On 14th July 1485, in Florence, Pacifico Massimi (1410?-1506), an Italian poet from Ascoli Piceno, published a little treatise in Latin entitled De componendo hexametro et pentametro libellus (A booklet on composing hexameters and pentameters). While the end of 15th and the beginning of 16th centuries were especially rich in metrical manuals and treatises, one characteristic of this little book makes it unique: it contained a mathematically adjusted paper instrument, a special tool invented by the author to help a novice poet. The instrument resembles a compass. It has a round base, printed on the page of the book, and consists of an arrangement of concentric circles, numbered with Roman numerals, with moving piece of different-sized arrows, all sewn into the centre of the circle system. By moving the mobile part of this ancient slide rule prototype, various results are given as the arrows show numerical values.