12 ON A PIECE OF CHALK 1 



/ The result of all these operations is, that we 

 know the contours and the nature of the surface- 

 soil covered by the North Atlantic for a distance 

 of 1,700 miles from east to west, as well as we 

 know that of any part of the dry land. It is a 

 prodigious plain one of the widest and most even 

 plains in the world. If the sea were drained off, 

 you might drive a waggon all the way from 

 Valentia, on the west coast of Ireland, to Trinity 

 Bay, in Newfoundland. And, except upon one 

 sharp incline about 200 miles from Valentia, I am 

 not quite sure that it would even be necessary to 

 put the skid on, so gentle are the ascents and 

 descents upon that long route. From Valentia 

 the road would lie down-hill for about' 200 miles 

 to the point at which the bottom is now covered 

 by 1,700 fathoms of sea-water. Then would come 

 the central plain, more than a thousand miles wide, 

 the inequalities of the surface of which would be 

 hardly perceptible, though the depth of water 

 upon it now varies from 10,000 to 15,000 feet ; 

 and there are places in which Mont Blanc might 

 be sunk without showing its peak above water. 

 Beyond this, the ascent on the American side 

 commences, and gradually leads, for about 300 

 miles, to the Newfoundland shore. 



Almost the whole of the bottom of this central 

 plain (which extends for many hundred miles in a 

 north and south direction) is covered by a fine 

 mud, which, when brought to the surface, dries 



