136 Sheppard : The Making of East Yorkshire. 



up of the mouths of the valleys in North-east Yorkshire by the 

 ice resulted in a number of lakes being formed, some of which 

 were of enormous dimensions. They have left unmistakable 

 traces of their former existence upon the land surface. In many 

 cases the continual draining- into these lakes by overfed streams 

 resulted in the waters eventually escaping through cols or 

 depressions upon the hills. The force of the waters escaping 

 from the lakes has left deep gorges in the hill sides, 

 which, though now dry, indicate the places where the water 

 escaped ; some of these are at great heights on the Cleve- 

 land moors. As in other parts of Yorkshire, and even in other 

 parts of Britain, these old lakes have been most carefully and 

 accurately mapped, and are known by such names as Lake 

 Pickering, Lake Humber, etc. 



As regards Lake Humber, this must have been a sheet of 

 water of truly gigantic proportions, as can be readily understood 

 if one assumes for the moment the probable effect of damming 

 the estuary to-day. In glacial times there were two barriers 

 across the Humber, one at Paull, and one crossing from North 

 Ferriby to South Ferriby. The latter is a most interesting 

 example ; on either bank are still the remnants of the moraine 

 which once existed at this point, and from clays and gravels^ 

 there exposed, ice-scratched stones, far-travelled boulders, and 

 other undoubted evidences of ice-action can be obtained. 



Let us imagine the probable appearance of East Yorkshire 

 on the final melting of the ice. Huge fans or sheets of 

 gravel occur at Bridlington and other places as a result 

 of the floods. Rounded hillocks of gravel and clay stand 

 out in all directions ; the hollows in between are filled with 

 water, forming' miniature lakes or meres. Of animal or plant 

 life there is little or none. The climate gradually becomes 

 milder ; at first Arctic plants and animals exist in small numbers. 

 Later, the margins of the meres become clothed in vegetation ; 

 peat is eventually formed, and huge trees of Oak and Fir thrive. 

 The Red Deer, Beaver, Short-horned Ox, Otter, and wild Horse 

 haunt the woods, and finally primitive man makes his appearance. 

 The latter is. able to hunt the animals in the forest. He lives 

 upon the holmes or islands which, in his day, stood out from the 

 surrounding morass. Since then, with the exception of Hornsea 

 Mere, all our marshes and meres have been drained, and their 

 sites are occupied by fertile fields ; but the place-names Marton, 

 Marfleet, Summergangs, Sand-le-Mere, and many others, in 

 which the word 'Mar' or 'Mere' occurs, indicate the former 

 existence of these sheets of water. Natur.-iW^^ 



