Abstract

The reason for printing yearly calendars, the type of which we are still using today, was to provide a sound health guide. Printed annual calendars were intended primarily to provide dependable information on when, on which days, and on where, on which body part, bloodletting might most conveniently be performed. Since antiquity bleeding had been one of the most common treatments for health care and hygiene, the practice continued through the Middle Ages and into the nineteenth century. Correct application had to take the position of the moon into consideration in accordance with the instructions of astrologia medica, iatromathematics. Favorable days for phlebotomy were first to be found in a so-called Lasstafeln, also called an almanac.