The operations of nature which have brought about the filling up of the hollows in the glacial land have been (1) the flow of water from wide drainage areas in Norfolk and Suffolk carrying silt into the lower parts and depositing it there,—(2) the incessant action of the sea in building up a shore boundary against itself, and blocking up the gaps in the glacial highlands through which its waters would flow inland. This action of the sea on our eastern coast is due to the inexhaustible supply of sand and shingle which is being constantly pushed along the shore southwards by the tidal wave. How persistent is the action of the sea in blocking up every outlet, whether river or harbour mouth, which man would wish kept open, has been a matter of costly experience to Yarmouth for some 800 years, as it has been to the Great Eastern Railway Company during the short time that they have undertaken the task of keeping open the mouth of Lowestoft Harbour. THE WAVENEY. The ground formed by the deposit of alluvial soil from the interior, and the drifting inwards of sand and shingle from the sea is in some places not easily distinguishable from the old glacial ground on which it has been imposed. As regards land well above high water mark, no doubt can arise however similar the sand of which it is composed may be to the sand on our shores. Such deposits must have been formed before the land had risen to its present level. But as regards deposits which are beneath or nearly on a level with high water mark, on the edge of what is now water or marsh-land, the difference in their origin may be difficult to ascertain and easily overlooked. The sand in our cliffs and on the shore is indeed the same:—the sea using the material which it has robbed from some projecting cliff, to fill up some bay or make an addition to the land to the southward. That the supposed ancient outlet between Lake Lothing and the sea was blocked up by sand and shingle in the same way as other outlets along the coast, was a very reasonable supposition, until the cutting of the channel for the new harbour disclosed a ridge of old glacial soil between the head of the lake and the sea, extending across the dip between Lowestoft and Kirkley, which proved that no deep river had ever flowed out there. This ridge was excavated to a depth of 30 feet below high water mark. “It consisted” Mr. Edwards tells us “not of horizontal stratified sand and shingle, as was found on the beach, but of precisely such strata of sand, as that of the rising ground on either side of the valley, the like of which may now be seen on Pope’s Farm.”