There is evidence that, towards the close of the mediaeval period, great storms and tidal inundations occurred on the shores of the North Sea and Baltic, and in the course of these floods, culminating in 1297, the Zuider Zee was formed from a lake that existed in its neighbourhood, by the breaking down of dykes.
He has produced various works on mediaeval church history and liturgies, among them being Henry VIII.
Some of his statutory lectures are published in his Lectures on Mediaeval and Modern History.
See Count Liitzow, Prague, in " Mediaeval Towns" Series (London, 1902); Tomek, Dejepis Mesta Pralay (History of the town of Prague), the standard work on Prague, which the author only continued up to the year 1608.
See Neubauer, Mediaeval Jewish Chronicles, ii.