Predictions at times fail because the exact time of birth is not known; or it is known approximately. The moment when the umbilical cord is cut is generally not noted. Hence one has to rectify the given time of birth. There are some methods given by the ancient texts. Some methods refer to the Moon and Mandi. Uttara Kalamrita offers a method based on the birth constellation and the weekday. Modifications to this are made by recent writers. These provide a stable background from which one can proceed. Nadi Rectification Tables also were prepared by some scholars of astrology. These are found wanting because the Tattvas are not clearly understood by the writers.
Then there are methods of rectification based on Directions. These refer to primary and secondary directions and also solar annual returns. An examination of these shows them incapable of rectifying the time of birth.There is Baily’s Prenatal Epoch. This is examined in detail. Finally symbolic directions are explained in detail. With the help of the important events in the past, the symbolic directions, it is maintained, will help us to rectify the time of birth within a minute or two.