John Smith — The Great Submergence. 499 



A few sentences may here be given from the report of the 

 Committee — 



"The highest part of the shelly clay in the 'main pit' is 

 503^ feet above sea-level. The deposit is 16 feet thick in that 

 section, and appears to be continuous for a distance of at least 

 190 yards in a well-nigh horizontal position." . ..." It contains 

 a small proportion of stones usually well-rounded and chiefly near 

 the base." .... " The shells are chiefly shallow-water species ; 

 some might have lived at a depth varying from 15 to 20 fathoms 1 

 . . . but the majority are littoral forms." . . . . " The shells on 

 the whole are remarkably well preserved, many retaining their 

 epidermis. They are neither rubbed nor striated." .... "The 

 pressure of the ice that formed the overlying 48 feet of Boulder-clay 

 would be sufficient to account for the crushing of certain shells, 

 the compression of the annelid tubes, and the production of the 

 system of cracks in the clay." 



These quotations agree perfectly with what I myself observed 

 at the Clava pit. I will now first attempt to show, having regard 

 to the facts of the case, that it is physically impossible that the 

 shelly clay with stones, or even the shells, can have been transported 

 uphill by ice. 



Stones may be carried long distances by ice, even uphill, without 

 being striated, but they must fall on the surface of a glacier. The 

 moment a stone reaches the bottom of the ice it will begin to be 

 striated. The shelly clay cannot possibly have fallen on the surface 

 of the ice, neither could it have been carried up under it without 

 many of the shells (if not all, in this case) having been striated. 

 Now, not a fragment of a striated shell has been found in the shelly clay. 



Neither are the stones in the shelly clay striated. This point 

 I can myself attest, as I superintended the washing of the stones 

 from which the percentages were taken, and only three of them 

 showed faint striations, two of the stones having been obtained 

 when I was present. A stone striated on one side had the mark of 

 attachment of a Balanus. It cannot therefore possibly have been 

 striated after the Balanus had grown on it. It was more likely to 

 have been a scratched stone washed out of the Lower Boulder-clay 



1 In the body of the report it is stated that some of the species still live at 

 100 fathoms. 



I asked Mr. J. T. Marshall, of Torquay, one of the authorities on recent shells, 

 to give me the depths at which some of the species found in the Clava section still 

 live, and he has furnished me with the following information : — 



Astarte compressa 3 to 2000 fathoms. 



,, sulcata 

 Leda pemula ... 



,, tenuis (pygmaea) 

 Nucula tenuis ... 



Tellina calcarea 



Natica Grcenlandica 

 Pleurotoma turricula ... 



,, Trevelyana 

 Trochus Groeulandicus ... 

 Trophon clathratus 



