THE SILTING UP OF THE ESTUARY. The natural process by which the valley of the Waveney became gradually filled up with silt, and covered with aquatic vegetation is carefully explained by Mr. Edwards. How many thousands of years the process was going on before nature had converted the wide and apparently deep estuary into an expanse of fen and bog, with the Waveney, the Yare, and the Bure, flowing through it in well defined channels we know not; but Mr. Edwards mentions an interesting fact showing that nature’s process of substituting land for water is still in progress. We know that some hundreds of years ago man took advantage of the work already done by nature, and converted these fens and morasses into dry marshlands by raising banks along the river sides to keep out the flood and tidal waters. Between these banks and the river there are margins several yards in breadth called “rands” or “ronds.” These rands have been left open to the overflow of the river, and they are found to be raised from one to two feet above the level of the inclosed lands on the other side of the banks. Another process by which nature has been and is still slowly substituting land for water is the advance of the reedy margins of the broads and the gradual diminution of the water area. BURGH CASTLE. The first evidence we have of the stage which the silting up process had reached during the time of man’s occupation of these parts are the records and vestiges of the presence of the Romans on the banks of the Yare and the Waveney during the first four centuries of the present era. In his account of Burgh Castle Mr. Suckling gives us a map shewing the different positions occupied by the Romans in these parts in connection with their system of coast defences against the Saxons, or other tribes on the opposite shores of the North Sea, whose piratical visitations were as much a cause of fear to the British inhabitants of our island as they were several hundred years later to its “Saxon” inhabitants themselves.