It is evident that the entire system from which all these various ancient systems of computation were derived was complex and profound, and that it comprised a mathematical knowledge having sound reason at the bottom of it, but whose keys have not yet been discovered. The competency of the computers is shown by their ability to ascertain with exactitude all natural cycles, such as those of the solar year and the eclipses, when such was their purpose; and this relieves them from the imputation that their secret and sacred years were due to ignorance and mal-observation. These cycles were not due to ignorance, but to a knowledge and a purpose which remains to be discovered by research free from both theological and scientific bias. The septenate of planets is of course a very familiar symbol in ancient lore; the number seven was recognized as the principal key-number in cosmic architecture. The reason why the sun and moon are included among the number of planets is not due to ignorance; and it is evident that such an alleged ignorance is not compatible with the knowledge displayed in other particulars. It was due to the fact that the real septenate of planets was esoteric, an item of arcane knowledge, and that when the septenate was mentioned exoterically, the place of two secret planets had to be supplied, the sun and moon being introduced for this purpose. The question whether the number of zodiacal signs was originally twelve or ten receives a suggestive hint from the fact that in the above calendar both a denary and a duodenary were used. The ten and the twelve are combined in some of these calendars by taking their least common multiple, 60, and using that number to designate a period of 60 years. Ten and twelve are likewise said to be combined by addition in the 22 letters of the Hebrew alphabet. From such gleanings of archaic science as are accessible to us, we may infer that it consisted largely in a marvelous application of fundamental mathematical principles to mensuration and the measurement of time. The computers, so far from being ignorant experimenters, were very brainy people, as we find some of their descendants to be still. The still unexplained existence of the very ancient Âryan Hindû astronomy of the _Sûrya-Siddhânta_ and other works, proves that, when exact calculation of natural cycles was the object, the calculators were fully as competent as ourselves. We must infer, then, that their secret and sacred cycles were based on the like competence and not upon ignorance.