Having set out the natural forces we have to deal with, we will proceed to consider their effect upon the outer approaches to the River Mersey. These approaches twenty-five years ago were very indifferent. The Bar only carried eight feet of water at low tide, and practically for vessels of any size Liverpool was a closed port for eighteen hours out of the twenty-four. By the employment of sand dredgers, which have removed millions of tons of sand, this difficulty has been overcome, but in deepening the Bar the Mersey Docks and Harbour Board have greatly added to the work which the ebb tide has to do. That work has to be supplemented by the almost continuous use of sand dredgers, and has been also assisted by the construction of the Revetment on the Taylor Bank. This has prevented the flood tide frittering its strength away over the Taylor Bank, and confines and concentrates the strength of the ebb stream; but still the formation of inconvenient lumps in the Crosby Channel suggests that the ebb tide has more than it can do. It has been suggested that by confining this channel with training walls constructed along the Burbo Bank and the Crosby shore the power of the ebb tide would be increased. It is, however, forgotten that the effect of training walls would be to diminish the volume of water, and therefore its sand-carrying capacity, and also that training walls along the Lancashire shore would rob the channel of the large amount of water now impounded at high water on the shore, which forms a valuable addition to the first part of the ebb. The changes in the outer estuary during the past fifty years have been quite remarkable. The old sea channel was the Rock Channel striking off to the west at the Rock Light, and the fairway was marked by two land marks which were prominent objects upon the Bootle shore; while the Hoylake and Leasowe Lighthouses indicated the fairway through the Horse Channel. The Rock Channel has shoaled, and is no longer used. The old Victoria Channel took its seaward course between the Great and Little Burbo Banks. This in process of time has shoaled and narrowed, and is no longer of any service, and the main channel pursues a north-west direction between the Little Burbo Bank and the Taylor Bank, and crosses the Bar through the new Queen's Channel. The Taylor Bank, which now stretches from the Crosby Lightship almost to the Bar is of recent formation, and takes the place of the Jordan Flats. The rapid growth of the Taylor Bank no doubt induced the Dock Board to construct the Revetment, and it has proved an effective bulwark against the rebound of the stream round Askew Spit, and its extension to the north seems to be desirable. The strong flood coming through the Crosby Channel is no doubt mainly accountable for the erosion which has taken place at Hightown, and which is now taking place at Hall Road. The latter can be prevented by the erection of a timber groin to give a south-west direction to the flood stream.