Adjustable Table

La chronologie rendue sensible; ou Nouveau calendrier perpétuel.
Paris: Chez tous les Marchands de Nouveautés, 1787. (BRB0261)

Useful for finding the dates of Christian holidays and other annual events, this French calendrical manual features several fold-out plates, three volvelles, twelve sliding paper strips for tracking the weekdays of every month, and the exhibited adjustable table for determining the major moveable feasts, such as Easter and Pentecost in any particular year. This table utilizes a cut-out window and a folded printed chart enclosed within a pocket formed by two consecutive leaves pasted together. The chart inside the pocket bears the dates of holidays specific to several common years, any of which could be selected, folded up, and reinserted inside the pocket, so that the pertinent dates could be seen through the window. In this copy, the folded chart evidently was never used, as it remains attached to the contemporary binding, and it still displays the dates for the year 1774, the example year in the directions for use, printed at the bottom of the page.