In preparing these instructions, Gaspard-Michel LeBlond, one of their authors, urges the use of uniform media for registering titles, suggesting that “ catalog materials are not diffi cult to assemble; it is suffi cient to use playing cards [. . .] Whether one writes lengthwise or across the backs of cards, one should pick one way and stick with it to preserve uniformity. ” 110 Presumably LeBlond was familiar with the work of Abb é Rozier fi fteen years earlier; it is unknown whether precisely cut cards had been used before Rozier. The activity of cutting up pages is often mentioned in prior descrip-tions.