In the first place, the fact that sun, moon, planets, and the signs of the zodiac shared the rule over the various organs of the body, and furnished positive intimations regarding the cause of the disease in question, made it unnecessary for the physician to trouble himself at all with an examination of the patient in order to ascertain cause and localization of the affection. One glance at the conjunctions of the stars was sufficient to show which organ of the patient happened to be endangered by the celestial constellation. If an individual complained, for instance, of disturbed digestion, and if the heavenly body that presided over the liver presented any remarkable phenomena, naturally only the liver was responsible for the case in question, and the diagnosis was made. Complications were to be expected if the stars which controlled the circulation of blood and mucus showed unfavorable signs. It was even possible for the physician well versed in astrology to determine in advance the period of time at which the occurrence of such humoral complications might be expected, as he had learned that the various hours of the day and of the night were to exert a powerful influence upon the juices of the body. For instance, Almanzor explains that the first three hours of day and of night are in closest relation to the blood, whereas the second quarters of day and of night hold sway over the yellow, the third over the black (bile), and the last quarters, finally, over the mucus. However, not only were the various hours of great importance to the course of the disease, but certain days of the disease—so-called critical days—were of still greater significance. It is true, the doctrine of these critical days was by no means the property of _Medicina Astrologica_, but the Corpus Hippocraticum already contained a book Περὶ χρίησὶμων. But the followers of Hippocrates had developed this theory only from humoro-pathological premises, and Galen, in his work χρήἱσιμαι ἡμέραι, had only included astrology in order to explain and to prove the entire doctrine of crises (compare also Sudhoff). He calculated in accordance with moon weeks and months, and in such a manner that a week counted six days and seventeen and one-half hours, and the month of the moon only twenty-six days and twenty-two hours. The seventh, fourteenth, twentieth, and twenty-seventh days were to be considered critical days of the first order. “Contemplate,” says Galen, “the critical days in the course of the moon in the angles of a geometrical figure of sixteen sides; if you find these angles in a favorable constellation, the patient will fare well; badly, however, if evil signs prevail.” But not only were certain hours and certain days of the week said to exert an important astrological influence upon the human body, such an influence was ascribed also to certain years. Such years were called “_Anni Scansiles_”—that is, “climacteric.” The expression “_Anni Climacterici_” was also used, but this designation has nothing in common with the modern conception of the climacteric. It was believed that the condition of the body underwent a thorough revolution during these climacteric years, and that a new stage, as it were, of organic life was reached. Heinrich von Rantzau, the astronomic aristocrat and statesman, accordingly defines the climacteric years as “_anni, in quibus ad sequentis temporis constitutionem sese vertat ætas et inflectat_.” Therefore, such years should in themselves harbor dangers for corporeal existence, and offer no favorable prospect for the course of diseases.