This book contains a horoscope for the year 1600. The Astrologers of that time called the Horoskop "Practic". This name looked more scientific. Ursinus started around 1575 publishing horoscopes for all years until 1600. In the following year he published the same book again without the last year. And so on. This book here is the last one. He never mentioned, whether his horoscope of the last year was right or wrong.
Georg Ursinus published 14 editions of his "Practiken". The forecast for one year contains the interesting astronomical data (eclipses, rare constallations of the planets and so on) , followed by an astrological interpretation. That means: forecast for climate, agriculture, wars, epidemic deseases of the people, living in that area of Germany and in foreign european countries and warnings to behave well and to believe in God.
Many people bought those books, many laughed about that.