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The Museum Gazette 



Egyptian and the Yorkshire river. In the former there are 

 no tides and in the latter the tidal flow, twice every day, is 

 very strong. The mud of the Nile is brought down from the 

 lake and high lands of its source, and is constantly being 

 carried downwards to its mouth. At the latter an immense 

 delta of mud has been and still is being formed. The 

 Humber is not forming any delta, and, as a matter of fact, 

 its water loses its treasure before it reaches the estuary. 

 At the latter it is quite clear, whereas at Selby, the Ouse, 

 which is continuous with it, is almost as thick as pea soup. 

 It is not, indeed, the Humber itself which is mud-laden, 

 but its tributaries, the Ouse, the Trent, and the Derwent. 

 Nor does the mud come from the inland sources of these 

 rivers. The streams in the beautiful Yorkshire dales are 

 clear enough except, perhaps, for a brown tinge of peat. 

 It is only certain middle portions of the rivers we have named 

 which carry available mud. There is none where they come 

 from and they lose it all before they get to the sea. The 

 farmer who wishes to warp his field does not congratulate 

 himself, as does his Egyptian brother, on exceptionally high 

 water, but provided only that the water rises high enough 

 to flood his land, prefers a moderate one. When the river 

 is very full, the water is thin and comparatively valueless. 



It has been to some writers a difficult problem as to where the 

 mud comes from. There need, however, be no mystery about it. 

 The rivers make it themselves. They are amongst the most 

 hotly tidal rivers in Britain. The water, at rise of tide, rushes 

 up them with great force. As a result their curves are con- 

 tantly altering ; land is torn away from one side and laid 

 down, in the form of silt, on the other. This has been going 

 on for ages, and the rivers now flow through valleys perfectly 

 level, which consist of deposited mud. If they had rocky 

 borders they would flow clear enough, but they run between 

 mud banks which they are constantly tearing away. What 

 wonder that the water in these districts becomes muddy. 

 This is, we fear, rather a commonplace ending to an ambitious 

 comparison, but it is the truth, and cannot be helped. 



