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Sundial, Brass Date: c. 1650 Maker: Workshop of Ulrich Schniep, Munich, Germany
This sundial was made for a bishop. The tiny cross was said to have been made from a fragment of Christ's cross. Inside the top are bone fragments from four Augsburg saints.

по поиску Workshop of Ulrich Schniep нашел статью http://www.antique-horology.org/_Editorial/schechner.pdf THE MATERIAL CULTURE OF ASTRONOMY IN DAILY LIFE: SUNDIALS, SCIENCE, AND SOCIAL CHANGE by SARA SCHECHNER, Harvard University
там похожие картинки, посмотрите, на солнечных часах помещали религиозные темы-сюжеты. На крестах действительно помещены деления.