"In years like 1887 and 1892, which differ from each other only in date of maximum gauge at Aswân, the river, having filled the basins in fifteen to twenty days instead of in twenty-five to thirty days, comes down to Cairo in so largely increased a volume that a really dangerous gauge of 25 cubits at Cairo is maintained for over a fortnight (the average October gauge in Cairo is about 23 cubits), and from September 10 to October 25 the river remains from 24 cubits to 25½ cubits, and the Middle Egypt basins discharge so slowly that the opening day is hardly traceable on the Cairo gauge. "In the 1878 flood, which was the most disastrous flood possible, the river rose in the most abnormal fashion, and on October 3 attained 18 cubits at Aswân. This breached the Delta, and in addition so delayed the Upper Egypt basins emptying, from the reason before given, that the wheat was sown too late, and got badly scorched by the hot winds of March and April."[67] CHAPTER XXIV. THE YEARS OF 360 AND 365 DAYS. Whether the Egyptians brought their year with them or invented it in the Nile valley, there is a belief that it at first consisted of 360 days only, that is, 5¼ days too little. It is more likely that they brought the lunar month with them, taking it roughly as 30 days (30 × 12 = 360), than that they began with such an erroneous notion of the true length of the solar year, seeing that in Egypt, above all countries in the world, owing to the regularity of the inundation, the true length could have been so easily determined, so soon as that regularity was recognised. We must not in these questions forget to put ourselves in the place of these pioneers of astronomy and civilisation; if we do this, we shall soon see how many difficulties were involved in determining the true length of such a cycle as a year, when not only modern appliances, but all just ideas too, were of necessity lacking. Since 360 days do not represent the true length of the year, it is clear that any nation which uses such a year as that will find the seasons and festivals sweeping through the year. Further, such a year is absolutely useless for the agriculturist, or the gardener, because after a time the same month, to say nothing of the same day of the month, will not mean reaping-time, will not mean sowing-time, or anything else. Still, it is right that I should state that all authorities are not agreed as to the use of this year of 360 days; at all events, during the times within our ken. Maspero[68] states:--