Rectangular pasteboard frame in which slides two cards bearing names of months and a movable calendar. Brass eyelets help one position the cards within windows. Names of weekdays above columns of dates in calendar window. Table 1 correlates years with key letters. Table 2 correlates key letters to first day of each month. List of months with their number of days. Reference tables for 150 years, beginning in 1800 and ending in 1950.
Inscription/Sig.
"B. G. BUTTON & CO., Publishers, Waterloo, Iowa. Copyright 1890".
