By W. Reward Bell, F.G.S. 



83 



I will now try to trace the events which led to the covering up 

 of these older rocks, and resulted in their becoming " the Buried 

 Rocks of Wiltshire " (shown in Section C). 



Eventually in that part of the Continent, where our Islands now 

 stand, several large salt lakes were formed, which were gradually 

 enlarged until they became inland seas, like the Caspian ; at the 

 bottom of these seas or lakes were laid down the great beds of salt, 

 which we find to this day in Cheshire and Worcestershire; but 

 no salt is found in Wilts or Somerset. The Mendips stood out as 

 an island in this lake or sea, and round their flanks the shores of 

 the sea formed shingle beaches, which, during the lapse of ages, 

 becoming conglomerates, still bear silent witness to the very different 

 aspect they bore in that bye-gone time, while further from those 

 shores sand and marl were deposited which are now the lowest 

 neozoic strata in Wilts and Somerset, and are represented by the 

 lowest beds in the series on the Sections A. and C. The geographical 

 conditions are shown in Map I., a large salt lake or inland sea lying 

 over the greater portion of England with the Mendips standing 

 out as an island. 



These deposits, formed at the bottom of this sea or lake, are, as 

 said before, the beginning of the secondary, or Neozoic period, and 

 are called the Triassic Rocks. It is in these newer or Triassic rocks 

 that the break referred to occurs. 



These Triassic rocks are also extremely interesting from the fact 

 that the first relics of mammalian life are found in them, being the 

 fossil remains of small marsupials. 



Continuing the history of the burial of the palaeozoic strata we 

 come to the Jurassic series, consisting of lias, oolite, and Oxford 

 clays. By reference to maps I. and II. it will be seen that a 

 gradual subsidence of the land surfaces had taken place, leading to 

 a connection between these inland seas and the open sea lying 

 to the south ; consequently oceanic and marine forms of life now 

 appear, at least we now find their fossilized remains ; but there is 

 no break, as in the previous change, from one series of rocks 

 to another, the change from the Triassic to the Jurassic being 

 gradual. 



G 2 



