Mr. Birks, in his “Elements of Prophecy,” pp. 368–372, distinctly acknowledges the “Cyclical character of the Prophetic Times,” and gives the numerators of the above series of ratios. He adds a very ingenious explanation of these cycles, and remarks that, “the highest prophetic period, 2300 years, is perhaps the only _secular_ cycle, composed of centuries, known to exist!” The _secular_ cycle of 5200, though not, as far as we are aware, a prophetic period, is “composed of centuries;” and being _five times_ the cycle of 1040 years, is so close an approximation to the truth, that it is within about 3¾ hours, and is therefore considerably more accurate than the cycle of 2300 years! What then does Mr. Birks mean in this passage? Perhaps the following sentence from Mr. Cuninghame’s “Scientific Chronology of the year 1839,” will supply the answer: “Moreover, 2300 years is the only centurial number, which is an original cycle in astronomy; for though we have a cycle of 5200 years, it is only as the multiple of the perfect one of 1040 by 5.” From the _fifth_ and _sixth_ ratios in the series, we obtain those of ³⁰⁄₃₇₁ and ⁴⁹⁄₆₀₆, which shows that _thirty_ years, the prophetic month, and _forty-nine_ years, the jubilean period, are also scientific cycles, but not possessing such close approximation to the truth as the larger cycles. In the same way, it may be easily proved, that the periods of 1290 years and 1078 years are scientific cycles; the former being _three times_ the prophetic period of pilgrimage and trial, namely 430 years, which is also a cycle of an inferior degree of approximation; and the latter being exactly _twenty-two_ jubilees.[35] CHAPTER V. DISCOVERY OF NEW MUNDANE CYCLES. 1. Mr. Cuninghame’s discovery of the mystical signification of the Seventy years’ Captivity—Its connection with the Era of the French Revolution—Confirmed by the sentiments of the modern Jews—Prediction of Rabbi Joseph Crool—Prediction in the Hebrew Tract, “Explanation of the Times,” published in 1794—The latter prediction not fulfilled—Hope concerning Israel.