70 SELECTED ESSAYS FROM LAY SERMONS 



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 in- 

 equalities of the surface of which would be hardly percep- 

 tible, 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 Newfound- 

 land shore. 



Almost the whole of the bottom of this central plain (which 

 extends for many hundred miles in a north and south di- 

 rection) is covered by a fine mud, which, when brought to the 

 surface, dries into a greyish white friable substance. You 

 can write with this on a blackboard, if you are so inclined; 

 and, to the eye, it is quite like very soft, greyish chalk. 

 Examined chemically, it proves to be composed almost 

 wholly of carbonate of lime; and if you make a section of it, 



of the Admiralty, 1858. They have since formed the subject of an 

 elaborate Memoir by Messrs. Parker and Jones, published in the 

 Philosophical Transactions for 1865. 



