The "whole month" in this case was evidently a full period of thirty days, irrespective of the particular phase of the moon when it began and ended. Amongst the Babylonians the sign for the word month was xxx, expressing the usual number of days that it contained, and without doubt amongst the Hebrews that was the number of days originally assigned to the month, except when the interval between two actually observed new moons was found to be twenty-nine. In later times it was learned that the length for the lunation lay between twenty-nine and thirty days, and that these lengths for the month must be alternate as a general rule. But in early times, if a long spell of bad weather prevented direct observation of the new moon, we cannot suppose that anything less than thirty days would be assigned to each month. Such a long spell of bad observing weather did certainly occur on one occasion in the very early days of astronomy, and we accordingly find that such was the number of days allotted to several consecutive months, though the historian was evidently in the habit of observing the new moon, for _chodesh_ is the word used to express these months of thirty days. We are told that-- "In the six hundreth year of Noah's life, in the second month, the seventeenth day of the month, the same day were all the fountains of the great deep broken up, and the windows of heaven were opened." And later that-- "After the end of the hundred and fifty days the waters were abated. And the ark rested in the seventh month, on the seventeenth day of the month, upon the mountains of Ararat." The five months during which the waters prevailed upon the earth were, therefore, reckoned as of thirty days each. If all the new moons, or even that of the seventh month, had been actually observed, this event would have been ascribed to the nineteenth day of the month, since 150 days is five months and two days; but in the absence of such observations a sort of "dead reckoning" was applied, which would of course be corrected directly the return of clear weather gave an opportunity for observing the new moon once again. A similar practice was followed at a much later date in Babylon, where astronomy is supposed to have been highly developed from remote antiquity. Thus an inscription recently published by Dr. L. W. King records that-- "On the 26th day of the month Sivan, in the seventh year, the day was turned into night, and fire in the midst of heaven."