Calendrier solaire, perpétuel et universel
A 1789 Paris almanac-style perpetual calendar by Alexandre Ruelle, printed for the author and the bookseller Bleuet fils, aimed at readers needing to compute dates and solar corrections. The pages are text-dense, with tables of meridian differences, day-of-week letter tables, leap-year lists and a numbered precept in small serif type, so a designer might take the strict tabular grid, ruled columns and centred letterpress headings as a model for dense technical information.
